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APPLIED  ANATOMY 


THE  CONSTRUCTION  OF  THE  HUMAN  BODY 

CONSIDERED    IN 

RELATION   TO  ITS  FUNCTIONS, 
DISEASES  AND  INJURIES 


BY 

GWILYM   G.  DAVIS 

M.D.,    UNIVERSITY   OF   PENNSYLVANIA    AND   GOETTINGEN  ;     M.R.C.S.,    ENG. ;    LL.D.,    LAFAYETTE 

"professor    of    ORTilOPEDIC    SURGERY   AND    FORMERLY   ASSOCIATE    PROFESSOR    OF   APPLIED    ANATOMY    IN    THE    UNI- 
VERSITY   OF     PENNSYLVANIA  ;     CONSULTING    SURGEON     TO    ST.    JOSEPH'S    HOSPITAL  ;     FORMERLY    SURGEON 
TO  THE   EPISCOPAL   HOSPITAL  ;     SURGEON     TO   THE   ORTHOPEDIC    HOSPITAL  ;    ORTHOPEDIC    SURGEON 
TO   THE    UNIVERSITY    AND    PHILADELPHIA    GENERAL    HOSPITALS  ;     FELLOW    OF    THE    AMERI- 
CAN    SURGICAL     ASSOCIATION,      THE       PHILADELPHIA     ACADEMY     OF     SURGERY    AND 
PHILADELPHIA     COLLEGE      OF     PHYSICIANS  ;      MEMBER     OF     THE     AMERICAN 
SOCIETY      OF      CLINICAL      SURGERY,     THE      AMERICAN       ORTHOPEDIC 
ASSOCIATION,      AMERICAN     ACADEMY      OF     MEDICINE,     ETC. 


WITH  SIX   HUNDRED    AND   THIRTY-ONE   ILLUSTRATIONS,  MOSTLY 
FROM  ORIGINAL  DISSECTIONS  AND  MANY  IN  COLOR 

BY 

ERWIN   F.   FABER 


FOURTH  EDITION 


PHILADELPHIA   &   LONDON 

J.  B.  LIPPINCOTT    COMPANY 


1S5708 


Copyright,  1910 
By  J.  B.  LippiNCOTT  Company 


Copyright,  1913 
By  J.  B.  LippiNCOTT  Company 


Copyright,  191 5 
By  J.  B.  LippiNCOTT  Company 


Copyright,  1916 
By  J,  B.  LippiNCOTT  Company 


Printed  by  J.  B.  Lippincott  Company 
The  Washi?tgtott  Square  Press,   Philadelphia,   U.  S.  A 


To 
GEORGE  A.  PIERSOL,  M.D.,  Sc.D. 

PROFESSOR  OF  ANATOMY  IN  THE  UNIVERSITY  OF  PENNSYLVANIA, 
AN  IDEAL  SCIENTIST,  TEACHER,  AND  FRIEND 


PREFACE  TO  FOURTH  EDITION. 


In  this  edition  there    have  been    a  few  corrections  to  the  cuts  and  text  and 

some  new  matter  added. 

The  Author. 
1814  Spruce  Street,  April,  1916. 


PREFACE  TO  SECOND  EDITION. 


In  this  edition  the  general  plan  of  the  work  has  been  retained.  The 
text  and  illustrations  have  been  carefully  revised  with  many  corrections  and 
additions.  The  cuts  have  been  made  more  accurate,  ten  have  been  entirely 
replaced  and  two  new  ones  added.  Our  thanks  are  extended  to  our  kindly 
critics   who   have   aided   us    in   making   the   book   more   accurate  and   useful. 


The  Author. 


1814  Spruce  Street,  January,  1913. 


PREFACE  TO  THE  FIRST  EDITION. 


It  is  not  the  object  of  this  work  to  teach  plain  anatomical  facts  ;  its  aim  is  to 
show  the  relation  of  structure  to  function,  whether  it  is  normal  function  or  function 
disturbed  or  impaired  by  injury  or  disease.  It  is  explanatory  and  utilitarian  in 
character,  and  not  encyclopedic.  The  bare  facts  of  anatomy  can  be  obtained  from 
the  systematic  treatises,  and  they  are  here  only  briefly  given  in  order  to  refresh  the 
memory  of  the  reader,  who  is  supposed  to  be  familiar  to  a  certain  extent  with 
systematic  anatomy.  A  person  who  has  studied  the  subject  only  from  a  systematic 
standpoint  cannot  utilize  and  apply  the  knowledge  so  acquired  unless  he  considers 
its  relation  to  the  various  affections  encountered  in  practice.  He  can  study  anatomy, 
but  he  will  not  see  its  application  until  it  is  pointed  out  to  him.  He  may  have 
studied  the  palmar  fascia,  but,  unless  he  is  shown  how  its  construction  influences  the 
course  of  pus  originatmg  beneath  it,  his  anatomical  knowledge  is  of  little  value. 
The  inability  to  make  any  practical  use  of  the  facts  or  to  see  their  application  is  the 
reason  why  anatomy  is  so  frequently  regarded  as  a  dry,  uninteresting  study  and  too 
often  designedly  neglected. 

In  considering  the  subject,  after  a  few  general  remarks  on  the  part  involved,  the 
skeleton  and  muscles  are  briefly  described,  and  thereby  one  is  enabled  to  understand 
the  surface  anatomy,  which  immediately  follows.  Then  comes  a  consideration  of  the 
various  affections  of  the  part,  with  such  allusion  to  the  nerves  and  vessels  as  is  desir- 
able to  elucidate  the  subject.  As  the  book  is  not  intended  to  be  a  systematic 
treatise  on  anatomy,  such  anatomical  facts  as  cannot  be  shown  to  be  useful  in  practice 
are  not  mentioned.  To  give  them  here  would  make  the  volume  too  large,  obscure 
its  main  object,  and  defeat  its  purpose. 

As  regards  the  anatomical  nomenclature  used,  there  is  no  system  so  generally 
accepted  as  to  justify  its  exclusive  adoption.  In  the  desire,  however,  to  aid  in  further- 
ing the  adoption  of  better  anatomical  terms,  as  much  of  the  BNA  terminology  has 
been  used,  or  included  in  parentheses,  as  a  consideration  of  the  subject  from  the 
standpoint  of  a  general  practitioner  would  allow. 

Most  of  the  illustrations  are  from  original  drawings  of  preparations  made  by  the 
author  and  his  assistants.  Those  derived  from  other  sources  are  duly  credited  ;  if 
there  has  been  any  failure  in  this  respect,  it  is  unintentional. 

The  clinical  material,  except  where  otherwise  stated,  is  from  the  author's  own 
experience. 

To  the  artist  in  charge,  Mr.  Erwin  F.  Faber,  and  to  Mr.  Herman  Faber,  who 
made  a  large  number  of  the  original  sketches,  my  best  thanks  are  due  for  their  great 
skill,  untiring  energy,  and  most  intelligent  aid  ;  their  work  speaks  for  itself. 


vi  PREFACE. 

I  am  under  great  obligations  to  many  friends  who  have  kindly  rendered  me  their 
aid.  Professor  George  A.  Piersol  has  given  me  much  valuable  information  and 
allowed  me  the  unstinted  use  of  his  anatomical  material  ;  Dr.  Astley  P.  C.  Ashhurst 
made  many  of  the  dissections  and  aided  in  correcting  and  preparing  the  manuscript 
for  the  press  ;  Dr.  Frank  D.  Dickson  did  most  of  the  proof-reading  and  prepared  the 
index  ;  Dr.  T.  Turner  Thomas  made  many  of  the  earlier  preparations  ;  and  Dr.  Henry 
Beates  aided  in  the  revision  of  the  first  portion  of  the  manuscript.  To  these  and 
others  who  have  contributed  to  the  formation  of  the  book  I  desire  to  express  my 
thanks. 

To  the  hearty  cooperation  and  unfailing  generosity  of  my  publishers  is  due  the 
presentation  of  such  an  attractive  volume.  I  asked  them  for  nearly  everything  I 
could  think  of,  and  they  gave  me  nearly  everything  I  asked  for. 

In  conclusion  :  this  work  is  recognized  as  being  far  from  complete,  but  it  is 
intended  to  be  suggestive  rather  than  absolute.  It  is  not  designed  so  much  to 
present  facts  as  to  furnish  reasons,  and  it  is  hoped  that  it  will  appeal  to  the  practising 
physician  and  surgeon  as  well  as  to  the  student. 

GwiLYM  G.  Davis. 
Philadelphia,  August,  1910. 


CONTENTS. 


THE    SCALP.  Page 

Skin I 

Superficial  Fascia i 

Occipitofrontalis  Muscle 2 

Subaponeurotic  Tissue 2 

Pericranium 2 

Subpericranial  Tissue 2 

Arteries  of  the  Scalp 3 

Temporal  Artery 3 

Occipital  Artery 3 

Lymphatics  of  the  Scalp 4 

Affections  of  the  Layers  of  the  Scalp. ...  4 

Affections  of  the  Blood-vessels 6 

Treatment  of  Vascular  Aft'ections  of  the 

Scalp 7 

Tumors  of  the  Scalp 7 

THE  SKULL. 

The  Skull  in  Childhood 8 

Fontanelles 8 

Dura  Mater g 

The  Skull  in  Adults 10 

Tables 10 

Sutures 10 

Frontal  Sinuses 10 

Mastoid  Process 11 

Suprameatal  Triangle 12 

Cerebral  Venous  Sinuses 12 

Practures  of  the  Skull 14 

Fractures  of  the  Skull  in  Children.  .  14 

Fractures  of  the  Skull  in  Adults. ...  15 
Fractures  by  Contrecoup  or  Counter 

Stroke 16 

Hemorrhage    in    Fractures    of    the 

Skull 16 

Injuries   to   Nerves   in   Fracture   of 

the  Skull 19 

THE  MENINGES. 

Dura  Mater 20 

Arachnoid 21 

Pia  Mater 22 

Affections    of    the    Membranes    of    the 

Brain 22 

Pachymeningitis 22 

Dural  Hemorrhage 23 

Meningitis 23 

Pial  Hemorrhage 23 

THE  BRAIN. 

Circulation  of  the  Brain 25 

Internal  Carotid  Artery 27 

Anterior  Cerebral  Artery 27 

Middle  Cerebral  Artery 28 

Posterior  Cerebral  Artery 28 

Cerebral  Softening 30 

Apoplexy 30 

Crossed  Paralysis 32 

Cortical  Apoplexy 32 

Cerebral  Lobes:  Frontal,  Parietal,  Occip- 
ital, Temporosphenoidal,  Central  Lobe 

or  Island  of  Reil 32 


Page 

Fissures  and  Convolutions  of  the  Brain. .  33 

Lateral  Surface  of  the  Hemispheres  ....  33 

Medial  Surface  of  the  Hemispheres  ...  34 
Functions  of  the  Cortex  of  the   Brain: 

Cerebral   Localization 34 

Functions  of  the  Convolutions  on  the 
surface  of  the  Cerebrum:  Prefrontal 
Area;  Midfrontal  Area;  Speech 
Centre  or  Broca's  Convolution;  Post- 
frontal  Area;  Rolandic  Area;  Sensory 
Area;     Visual   Area;     Auditory  Area; 

Gustatory  Area;    Olfactory  Area.  ...  35 

Functions  of  the  Basal  Ganglia 37 

Corpus  Striatum  and  Thalamus.  ...  37 
Corpora  Quadrigemina,  Crura  Cere- 
bri, Pons  Varolii 38 

The  Corona  Radiata,   Internal  Capsule, 

and  Motor  Tract 38 

Craniocerebral  Topography 39 

Bony   Landmarks;      Topographical 

Points 40 

The  Lower  Level  of  the  Brain 40 

Fissures  and  Convolutions 40 

Subsidiary  Fissures,  Convolutions  .  41 

The  Fissures  in  Children 42 

The  Lateral  Ventricles 43 

Cerebral  Abscess — Trephining 44 

THE  FACE. 

The  Frontal  Region 45 

The  Temporal  Region 46 

The  Temporal  Fascia 47 

The  Region  of  the  Cheek 49 

Parotid  Gland 51 

The  Upper  Jaw 54 

The  Lower  Jaw 63 

The  Region  of  the  Eye .  72 

The  Eyeball  and  Optic  Nerve 77 

The  Eyelids  and  Conjunctiva 82 

The  Lachrymal  Apparatus 83 

The  Ear 84 

Operations  on  the  Middle  Ear 90 

The  Nose 94 

Frontal  Sinus loi 

Ethmoidal  Sinuses 102 

Sphenoidal  Sinus,  Maxillary  Sinus.  .  103 

THE  MOUTH  AND  THROAT. 

The  Tongue 107 

Roof  of  Mouth in 

Palatal  Arches 112 

Faucial  Tonsils 113 

Retropharyngeal  Abscess 116 

The  Pharynx 117 

Eustachian  Tube 118 

Pharyngeal  Tonsil 122 

The  Larynx 124 

THE  NECK. 

Surface  Anatomy 128 

Cervical  Triangles 131 

Torticollis 140 

vii 


VIU 


CONTENTS. 


Page  ( 

Ligation  of  Arteries 141 

The  Cervical  Fascias 150 

Lymphatics  of  the  Neck 156  , 

Operations  on  the  Air  Passages 161 

Operations  on  the  Thyroid  Gland 163 

The  Parathyroid  Bodies 165 

Oesophagus — Cervical  Portion 166 

Cut-throat 168 

Afifections  of  the  Neck 169 

THE  THORAX. 

Sternum,  Ribs,  and  Costal  Cartilages  .  .  174 

Thoracic  Vertebrae 176 

Soft  Parts  of  Chest 176 

Muscles  of  Chest 177 

Surface  Anatomy  of  Thorax 180 

Breast  or  Mamma 182 

Lymphatics  of  Breast 184 

Abscess  of  Breast;    Tumors 185 

Excision  of  Breast 187 

The  Mediastinum 187 

Pleural  Effusions 191 

The  Chest  Contents 192 

Longitudinal  lines;   Regions 192 

The  Pleurae 194 

The  Lungs 196 

Pericardium 201 

The  Heart 204 

The  Aorta 208 

The  Oi^sophagus 211 

The  Thoracic  Duct 214 

THE  UPPER  EXTREMITY. 

The  Shoulder-Girdle 217 

Bones  of  the  Shoulder 219 

Shoulder-Joint 222 

Muscles  of  the  Shoulder 226 

Surface  Anatomy 227 

Axilla 229 

Dislocations  of  the  Clavicle 230 

Dislocations  of  the  Shoulder 232 

Fractures  of  the  Clavicle 241 

Fractures  of  the  Scapula 243 

Fractures  of  the  Upper  end  of  the  Hu- 
merus      244 

Epiphyseal  Separations 247 

Amputation  at  the  Shoulder-Joint 247 

Interscapulothoracic  Amputation 250 

Excision  of  the  Clavicle 250 

Excision  of  the  Scapula .  251 

Excision  of  the  Head  of  the  Humerus.  .  251 
Diseases  of  the  Shoulder- Joint  and  Bursas  253 

Axillary  Vessels 257 

Axillary  Lymphatics 263 

Abscesses  of  Axilla 264 

THE  ARM. 

The  Humerus 267 

Muscles  of  the  Arm 267 

Intermuscular  Septa 271 

Surface  Anatomy 271 

Brachial  Artery 272 

Amputation  of  the  Arm 275 

Fractures  of  the  Humerus 276 

Operations  on  the  Arm 279 

REGION  OF  THE  ELBOW. 

Bones  of  the  Elbow 280 

Elbow-Joint 282 

Muscles  of  the  Elbow 284 


Page 

Surface  Anatomy 287 

Veins  of  the  Elbow 288 

Brachial  Artery 290 

Dislocations  of  the  Elbow 291 

Fractures  in  the  Region  of  the  Elbow.  .  .    295 
Diseases  of  the  Olecranon  Bursa;  Diseases 

of  the  Elbow-Joint 300 

Resection  of  the  Elbow 301 

Amputation  at  the  EIVjov/ 302 

THE  FOREARM. 

Bones 303 

Movements  of  Pronation  and  Supination  304 

Muscles 305 

Surface  Anatomy 312 

Arteries 3  14 

Nerves 317 

Fractures 321 

Amputation 326 

Operations 328 

REGION  OF  THE  WRIST. 

Bones  of  the  Wrist 330 

Inferior  Radio-ulnar  Articulation 332 

Wrist-Joint 333 

Anterior  Annular  Ligament 335 

Posterior  Annular  Ligament 336 

Surface  Anatomy  of  the  Wrist 338 

Compound  Ganglion 342 

Fractures  of  the  lower  end  of  the  Radius 

and  Ulna 342 

Dislocations  at  the  Wrist 345 

Excision  of  the  Wrist 347 

Amputation  at  the  Wrist 347 

THE  HAND. 

Bones  of  the  Hand 349 

The  Phalanges 351 

Joints 352 

Muscles 353 

Surface  Anatomy 354 

Palmar  Fascia 357 

Arteries 358 

Nerves 360 

Dislocations 362 

Fractures 364 

Wounds 364 

Abscesses 365 

Lymphatics 368 

Amputations 368 

THE  ABDOMEN. 

Surface  Anatomy 370 

Abdominal  Viscera 372 

Abdominal  Walls 374 

Muscles  of  the  Abdomen 375 

Vessels  of  the  Abdominal  Walls 378 

Abdominal  Incisions 381 

Herniae 3*^2 

Umbilical 383 

Inguinal  Congenital 383 

Acquired  Inguinal  Hernia 385 

Radical  Cure 387 

Femoral  Hernia 390 

The  Lumbar  Region 392 

Lumbar  Fascia 393 

Lumbar  Abscess 394 

Lumbar  Incisions 395 

The  Interior  of  the  Abdomen 396 

Peritoneum 396 


CONTENTS. 


IX 


Page 

Abdominal  Viscera 399 

Stomach 401 

Affections  of  the  Stomach 403 

Operations  on  the  Stomach.  . . .  405 

The  Small  Intestine 406 

Duodenum 408 

Jejunum  and  Ileum;  Operations  409 

The  Mesentery 410 

The  Large  Intestine 411 

Caecum  and  Appendix 414 

Appendicitis 414 

The  Colon 414 

The  Liver 416 

Wounds  and  Injuries 417 

Abscess 420 

Gall- Bladder  and  Biliary  Passages.  420 

Gall-Stones 422 

The  Pancreas 422 

Cysts  and  Abscesses 423 

The  Spleen 424 

Splenic  Enlargement 424 

Wounds 424 

The  Kidneys 424 

Displacement  of  the  Kidneys.  .  427 

Tumors  of  the  Kidney 427 

Abscess  of  the  Kidney 428 

Operations  on  the  Kidney.  .  .  .  428 

The  Suprarenal  Gland 438 

The  Ureter  and  Renal  Pelvis 430 

Operations  on  the  Ureter 43  i 

THE  PELVIS. 

Pelvic  Walls 434 

Pelvic  Floor 435 

Pelvic  Fascia 436 

Iliac  Vessels 438 

Pelvic  Viscera 438 

Rectum  and  Anal  Canal 440 

Blood-Vessels 442 

Affections  of  Rectum  and  Anus  442 

Imperforate  Anus 442 

Hemorrhoids 443 

Fistula 443 

Fissure 443 

Excision  of  Rectum 444 

Bladder 447 

Bladder  in  the  Female 448 

Cystoscopic  Examination..  .  .  ,.  448 

Operations  on  the.  Bladder.  .  .  .  448 

Prostate 450 

Hypertrophy 450 

Prostatectomy 451 

Abscess 452 

Seminal  Vesicles 453 

Vas  Defferens 454 

Development  of  the  Urogenital  System  .  454 

Female  Generative  Organs 454 

Uterus 456 

Ovary 456 

Fallopian  Tubes 457 

Vagina. 457 

Ureter  in  the  Female 458 

Blood-Vessels 458 

Lymphatics ; 459 

Pelvic  Examinations 459 

Operations  on  the  Female  Pelvic  Organs  460 

Hysterectomy 461 

Oophorectomy 461 

Vaginal  Hysterectomy! 462 

The  Female  External  Genitals 462 

Clinical  Considerations 463 

Female  Perineum 464 


Page 

Male  External  Genitals.  ...    465 

Penis 465 

Scrotum 467 

Testicles 468 

Epididymis 468 

Spermatic  Cord 469 

Urethra 470 

Muscles 471 

Passage  of  Sounds  and  Cathe- 
ters   471 

The  Male  Perineum 472 

The  Perineal  Fascias 473 

The  Perineal  Spaces 474 

Practical  Application 475 

Rupture  of  the  Urethra 475 

Median  Lithotomy 475 

Lateral  Lithotomy 476 

Anal   Triangle   and   Ischiorectal 

Region 476 

THE  BACK  AND  SPINE. 

Surface  Anatomy 477 

The  Vertebral  Column 478 

Curves 478 

Movements 478 

Deformities  of  the  Spinal  Column.  .  47S 

Kyphosis 479 

Lordosis 479 

Scoliosis 479 

Affections  of  the  Spinal  Column.  .  .  481 

Injuries  of  the  Spinal  Column 482 

Spinal  Cord  and  its  Membranes  ....  483 

Transverse  Spinal  Lesions 484 

Spinal  Meninges 484 

Spinal  Hemorrhage 486 

Functions     of     the     Cord     and     Spinal 

Localization 487 

Lesions  of  the  Cord 487 

Operations  on  the  Spine 488 

THE  LOWER  EXTREMITY. 

General  Considerations 489 

The  Bony  Pelvis 489 

Mechanisim  of  the  Pelvis 490 

Fractures  of  the  Pelvis 491 

Attachment  of  the  Lower  Extremities  to 

the  Trunk 491 

Anteroposterior  Equilibrium 492 

Lateral  Equilibrium 493 

Deviations    of    the     Spine    above    the 

Sacrum 495 

Distortions  Accompanying  Affections  of 

the  Lower  Extremities 496 

Measurement  of  the  Lower  Limbs 497 

Walking 498 

THE   REGION   OF  THE   HIP. 

Bones  of  the  Hip 499 

Muscles  of  the  Hip 503 

Surface  Anatomy 504 

Ligation    of    the    Gluteal,    Sciatic,   and 

Internal  Pudic  Arteries 505 

The  Hip-Joint 506 

Dislocations  of  the  Hip 508 

Mechanism  of  the  Production  of .  .  .  509 

Reduction  of 512 

Congenital  Luxations  of  Hip 514 

Coxalgia 515 

Hip  Abscess 516 

Coxa  Vara 517 


CONTENTS. 


Page 

Coxa  Valga 517 

Operations  on  the  Hip-Joint 517 

Lateral  Operations 517 

Anterior  Operations 519 

Inferior  Operations $iq 

THE  THIGH. 

Muscles 520 

Surface  Anatomy 522 

Scarpa's  Triangle 522 

Femoral  Artery 523 

Hunter's  Canal 524 

Long  Saphenous  Vein 525 

Lymphatics 527 

Sciatic  Nerve 527 

Fractures  of  the  Femur 529 

Fracture  of  Neck 529 

Fracture      through      the     Trochan- 
ters   531 

Fracture  of  the  Shaft 53 1 

Amputation  at  the  Hip-Joint 532 

Amputation  of  the  Thigh 532 

REGION  OF  THE  KNEE. 

Surface  Anatomy 533 

The  Knee-joint 534 

Movements 534 

Bones 534 

Ligaments 535 

Bursae  of  the  Knee 538 

Fracture  of  the  Patella 539 

Dislocation  of  the  Patella 540 

Dislocation  of  the  Knee 541 

Dislocation     of     the     Semilunar     Carti- 
lages    541 

Epiphyseal  Separations 541 

Resection  of  the  Knee 542 

Tuberculous     Disease     of      the     Knee- 
joint  543 

Knock- Knee  and  Bow-Legs 543 

Osteotomy 544 

Ligation  of  the  Popliteal  Artery 544 

Amputation  through  the  Knee-joint  . .  .  544 

THE  LEG. 

Surface  Anatomy 546 

Muscles  of  the  Leg 546 

Fascia  of  the  Leg 548 

Arteries  of  the  Leg 548 

Veins  of  the  Leg 550 

Varicosities  of 550 

Lymphatics  of  the  Leg 551 

Fractures  of  the  Leg 551 

Amputation  of  the  Leg 552 


REGION  OF  THE  ANKLE. 

Pagb 

Surface  Anatomy 553 

Ankle-joint 554 

Ligaments 554 

Movements 554 

Tuberculosis  of  the  Ankle 555 

Excision  of  the  Ankle 555 

Sprain  of  the  Ankle 556 

Dislocations  of  the  Ankle 556 

Fractures  of  the  Ankle 557 

Fracture    by     Eversion    or     Pott's 

Fracture 557 

Fracture  by  Inversion. 558 

Amputations  at  the  Ankle 559 

Syme's 559 

Pirogofif's 560 

REGION  OF  THE  FOOT. 

The  Construction  of  the  Foot 561 

Diseases  and  Injuries  of  the  Foot 561 

Treatment  of  Affections  of  the  Feet.  .  .  .  562 

Bones  of  the  Foot." 562 

Arch  of  the  Foot 563 

Joints  and  Ligaments  of  the  Foot 564 

The  Ligamentous  Support  of  the  Arch 

of  the  Foot 566 

Muscles  of  the  Foot 568 

Action  of  the  Muscles  in  Supporting 

the  Arch 568 

Action   of   the   Muscles  as    Flexors 

and  Extensors 569 

Action  of  the  Muscles  as  Abductors 

and  Adductors 570 

Surface  Anatomy  of  the  Foot 570 

Tendons  of  the  Foot 571 

Joints  of  the  Foot 572 

Arteries  of  the  Foot 572 

Amputations 574 

Chopart's 575 

Lisfranc's 575 

Plantar  Abscess 575 

Deformities  of  the  Feet 576 

Talipes  Varus 576 

Talipes  Valgus 577 

Flat  Foot 577 

Talipes  Equinus 578 

Talipes  Calcaneus 578 

Talipes  Cavus 578 

Hallux  Valgus 579 

The  Toes 579 

Ingrown  Nail 579 

Hammer  Toe 579 

Luxation  of  the  Toes 580 

Metatarsalgia 580 

Resection  of  the  Metatarsophalan- 
geal Joint 380 

Amputation  of  the  Toes 581 


APPLIED  ANATOMY. 


THE  SCALP. 


The  scalp  is  formed  by  the  movable  soft  tissues  which  cover  the  skull.  It  is 
composed  of  three  layers:  skin,  superficial  fascia,  -awA  occipitofrontalis  muscle  \\'\\h 
its  aponeurosis.  It  is  attached  to  the  underlying  pericranium  by  loose  connective 
tissue  called  the  subaponeurotic  layer.  The  pericr'anium,  or  periosteum  of  the  skull, 
is  loosely  attached  to  the  bones  by  a  small  quantity  of  connective-tissue  fibres  called 


Epicranial  aponeurosis 

Superficial  fascia 

Skin 


by  some  anatomists  the  subpericranial  connective  tissue.  At  the  sutures,  however,  it 
is  very  firmly  attached. 

The  principal  affections  of  the  scalp  are  wounds,  inflammation,  affections  of 
the  blood-vessels,  tumors,  and  neuralgia.  The  peculiarities  of  these  affections  are 
determined  by  the  anatomical  structure  of  the  parts. 

The  skin  of  the  scalp  is  probably  the  thickest  in  the  body,  although  not  so 
dense  as  that  of  the  heel.  Besides  the  hair,  it  contains  abundant  sweat  and  sebaceous 
glands.  These  latter  are  connected  with  the  hair-follicles  and  are  near  the  surface. 
The  skin  increases  in  thickness  from  the  frontal  to  the  occipital  region. 

The  superficial  fascia  consists  of  a  net-work  of  connective-tissue  fibres  which 
run  from  the  skin  above  to  the  aponeurosis  of  the  occipitofrontalis  below.  In  its 
meshes  are  fat,  blood-vessels,  nerves,  and  lymphatics.  The  hair-bulbs  often  pierce 
the  skin  and  extend  into  this  layer. 

The  fibres  of  the  superficial  fascia  bind  the  skin  so  firmly  to  the  aponeurosis 
beneath  that  when  the  skin  is  moved  the  aponeurotic  layer  is  carried  with  it.     The 


2  APPLIED   ANATOMY. 

arrangement  of  the  fibres  is  shown  in  Fig.  3.  P'ibres  starting  from  the  point  A  not 
only  pass  directly  down  to  B,  but  also  to  each  side  to  the  points  Cand  D.  In  the 
same  way,  fibres  starting  from  B  not  only  pass  upward  to  A,  but  also  forward  to  E 
and  backward  to  F.  Now,  if  the  skin  is  moved  in  the  direction  of  the  forward  arrow, 
the  fibres  E  B  and  A  D  are  tightened  and  drag  the  aponeurosis  forward.  If  the  skin 
is  moved  in  the  direction  of  the  backward  arrow,  the  fibres  A  C  and  F B  are  tight- 
ened and  so  drag  the  aponeurosis  backward.  Thus  it  is  seen  that  the  aponeurosis 
must  follow  the  movements  of  the  skin. 

The  occipitofrontalis  muscle  with  its  aponeurosis  arises  from  the  supe- 
rior curved  line  of  the  occiput  and  is  inserted  into  the  skin  of  the  frontal  region. 


Skin 

Super 

Aponeurosis 

Subaponeurotic  connective  tissue 

Pericranium 
_      Subpericranium 

•4 Skull 

!  — Uuta  mater 


Merkel  describes  the  epicranial  aponeurosis  as  dividing  into  two  layers,  one  inserting 
into  the  skin  and  the  other  into  the  rim  of  the  orbit  {Haiid.  der  top.  Anat.  Bd.  i,  p. 
17).  The  bellies  of  the  muscle  are  comparatively  short,  about  5  cm.  in  length,  the 
remaining  tissue  extending  between  them  constituting  the  aponeurosis.  As  it  comes 
downward  from  the  temporal  ridge,  over  the 
sides  of  the  head,  the  aponeurosis  becomes 
thinner  and  gives  attachment  by  its  superficial 
surface  to  the  anterior  and  superior  auriadar 
muscles.  It  then  proceeds  downward  to  be 
attached  to  the  upper  edge  of  the  zygoma. 


Skin 


\:ioneurosis 


Fig.  3. — Diagram  illustratitiK  the  melhod  of  attach- 
ment of  theskin  to  the  aponeurosis  of  the  occipitofrontalis 
muscle. 


Fig.  4. — Showing  now  the  periosteum  in 
childhood  dips  between  the  bones  in  the  line  of 
the  sutures. 


Contraction  of  the  occipitofrontalis  muscle  causes  the  skin  of  the  forehead  to  wrinkle 
transversely.  It  is  a  muscle  of  expression,  and  blends  with  the  pyraniidalis  nasi 
and  corrugator  supercilii.      It  is  supplied  by  branches  of  the  facial  nerve. 

The  subaponeurotic  tissue  is  very  loose  and  abundant,  so  that  it  does  not  tend 
to  confine  the  movements  of  the  scalp,  but  favors  them.  Hence  the  scalp  is  readily 
torn  loose  from  the  skull  in  scalping,  machinery  accidents,  etc.  This  tissue  is  so 
loose  that  effusions  accumulate  here  and  spread  extensively.  It  contains  only  a  few 
blood-vessels. 

The  pericranium  in  its  normal  condition  is  a  thin,  tough  membrane  containing 
few  blood-vessels.  Except  at  the  sutures,  where  it  is  firmly  attached  and  dips 
down  between   the  bones,   it  is  comparatively  easily  stripped  from   the  skull  and 


THE   SCALP.  3 

does  not  convey  much  nourishment  to  it.  It  is  deficient  in  osteogenetic  or  bone- 
forming  properties,  so  that  when  it  is  raised  off  the  skull  in  operations,  and  the 
bone  removed  from  beneath,  as  occurs  in  trephining,  fractures,  etc. ,  new  bone  is  not 
produced. 

The  subpericranial  tissue  is  so  scanty  and  loose,  particularly  in  infancy,  that 
it  readily  allows  the  pericranium  to  be  raised  and  effusions  to  occur  beneath. 


THE  ARTERIES  OF  THE  SCALP. 

The   scalp    is  supplied    by  the   frontal,  supra-orbital,   and  sometimes  a   small 
branch  from  the  lachrymal  arteries,  from  the  ophthalmic;  by  the  temporal,  through 


Temporal 


Transverse  facial 


Posterior  auricular 
Occipital 


Fig.  5. — Arteries  of  the  scalp. 


its  anterior  and  posterior  branches;  and  by  the  posterior  auricular  and  the  occipital 
arteries  from  the  external  carotid.  These  arteries  communicate  freely  with  each 
other,  not  only  laterally,  but  also  across  the  top  of  the  scalp.  It  is  not  unusual  to 
see  a  large  branch  of  the  temporal  communicating  directly  with  the  occipital. 

The  temporal  artery  begins  in  the  substance  of  \.h&  parotid  gla7id,  just  below 
the  condyle  of  the  jaw,  and  mounts  over  the  zygoma,  a  centimetre  (or  less)  in  front 
of  the  ear.  It  lies  on  the  temporal  fascia  and  its  pulsations  can  be  felt  at  this  point, 
if  desired,  during  the  administration  of  an  anaesthetic.  About  four  centimetres  ( 1 5^ 
in. )  above  the  zygoma,  it  divides  into  the  anterior  and  posterior  branches.  The 
auriculotemporal  branch  of  the  fifth  nerve  lies  just  in  front  of  the  ear  and  between  it 
and  the  temporal  arterv. 

The  occipital  artery  mounts  to  the  scalp  in  the  interval  between  the  pos- 
terior border  of  the  steniomastoid  muscle  and  the  anterior  border  of  the  trapezius. 
It  is  about  midway  between  the  posterior  border  of  the  mastoid  process  and  the 
occipital  protuberance.     If  it  is  desired  to  expose  it  from  this  point  forward,  the 


APPLIED   ANATOMY. 


sternoniastoid,  splenius  capitis,  and  tracheloniastoid  muscles  will  have  to  be  cut, 
because  it  passes  beneath  them.  The  occipitalis  major  nerve  lies  to  the  inner  side  of 
the  artery. 


Occipital  artery 


Complexus 

Inferior  oblique 

Trapeziu; 

Trachelomatoid 

Splenius' 


Levator  angul 
scapulae 


Superior  oblique 

Sternoniastoid 
Tracheloniastoid 
Splenius 


Spinal  accessory 
nerve 


Hypoglossal  nerve 


Fig.  6. — Occipital  artery. 

LYMPHATICS  OF  THE  SCALP. 

The  lymphatics  anteriorly  near  the  median  line  pass  down  between  the  orbits  to 
reach  the  submaxillary  nodes.  Those  of  the  anterior  parietal  and  temporal  regions 
empty  into  the  pre-auricular  nodes;  those  of  the  posterior  parietal  and  temporal, 
into  the  nodes  behind  and  below  the  ear;  and  those  of  the  occipital  region  into  the 
occipital  nodes.  Infectious  troubles  of  these  regions,  therefore,  will  cause  enlarge- 
ment of  the  corresponding  nodes. 

AFFECTIONS  INVOLVING  THE  LAYERS  OF  THE  SCALP. 

Wounds  of  the  scalp  are  common.  Incised  wounds  bleed  more  freely  and  the 
hemorrhage  is  more  difficult  to  control  than  in  wounds  elsewhere  on  the  surface. 
This  is  due  to  the  exceedingly  free  blood  supply  and  to  the  peculiar  arrangement  of 
the  blood-vessels  in  the  tissues. 

Small  wounds  of  the  scalp  do  not  gape,  particularly  if  they  are  longitudinal  in 
direction  and  not  very  deep.  The  skin  is  so  intimately  bound  to  the  aponeurosis 
beneath  that  displacement  is  impossible.  If  the  cut  is  deep  enough  to  divide  the 
aponeurosis  extensively,  especially  if  the  wound  is  transverse,  gaping  is  marked. 
This  is  produced  by  contraction  of  the  two  bellies  of  the  occipitofrontalis  muscle, 
which  pulls  the  edges  apart. 

Bleeding  is  apt  to  be  persistent  and  hard  to  control  because  the  arteries  running 
in  the  deep  layers  of  the  skin  and  fibrous  trabeculae  are  firmly  attached  and,  there- 
fore, when  cut,  their  lumen  cannot  contract  nor  their  ends  retract.  When  large 
flaps  are  torn  in  the  scalp,  they  rarely  die  because  of  their  free  blood  supply,  and 
sloughing  is  limited  to  the  parts  which  are  actually  contused.  As  the  subaponeur- 
otic space  is  often  opened,  if  the  wound  is  sewed  too  tightly  shut,  subsequent  bleeding 
instead  of  escaping  externally  may  extend  widely  under  the  aponeurosis.  Inasmuch 
as  hair  and  dirt  are  often  crushed  into  these  wounds,  great  care  should  be  taken  to 


THE   SCALP.  5 

disinfect  them.  A  cut  will  open  the  hair  bulbs  and  sebaceous  glands,  and,  as  the  hairs 
project  into  the  subcutaneous  tissue,  they  may  serve  as  a  starting  point  for  infection. 

Contraction  of  the  occipitofrontalis  muscle  may  prevent  healing  in  extensive 
wounds.     To  avoid  this  the  scalp  is  covered  by  a  recurrent  bandage  or  otherwise  fixed. 

Lacerated  wounds  do  not  bleed  so  freely  as  do  incised  wounds,  but  they  are 
accompanied  by  a  more  extensive  loosening  of  the  scalp.  Large  flaps  of  tissue  are 
frequently  raised  and  turned  to  one  side.  The  most  severe  of  these  injuries  have  been 
produced  by  the  hair  being  caught  by  a  revolving  shaft,  tearing  nearly  the  whole 
scalp  off.  Its  loose  attachment  to  the  pericranium  and  bone  beneath  by  the  loose 
subaponeurotic  tissue,  readily  explains  the  reason  of  these  extensive  detachments. 

Contusions  cause  only  a  moderate  amount  of  swelling,  which  is  usually  circum- 
scribed. While  the  skin  is  not  broken,  the  blood-vessels  and  other  tissues  beneath 
are  often  ruptured,  and,  therefore,  extravasation  of  blood  occurs.  When  this  is  con- 
fined to  the  superficial  fascia,  it  is  small  in  amount  and  limited  in  area.  It  does  not 
tend  to  work  its  way  for  any  great  distance  beneath  the  skin.  If  the  extravasation 
extends  below  the  aponeurosis,  it  may  cover  a  considerable  area  of  the  skull.  When 
it  occurs  beneath  the  pericranium  it  is  called  cephalhcematoma,  or  in  the  new-born 
capnl  succedaneum.  Caput  succedaneum  is  found  almost  always  on  the  right  side, 
involving  the  parietal  eminence.  It  is  limited 
by  the  attachment  of  the  pericranium  at  the 
sutures. 

Hcs7natomas  of  the  scalp  possess  the  pecu- 
liarity of  being  soft  in  the  centre  and  sur- 
rounded by  a  hard  cedematous  ring  of  tissue. 
In  cephalhaematoma  of  long  standing  this  ring 
may  ossify,  and  the  new  bone  may  even  extend 
and  form  a  more  or  less  perfect  bony  cyst. 
This,  however,  is  very  rare. 

Hsematomas  produced  by  blows  on  the 
head  are  often  mistaken  for  fractures.  The 
raised  edge    is  so    hard  as    sometimes   to  be 

thought  to  be  the  edge  of  broken  bone.    The  tis-  Fig  7.— Haematoma  on  the  forehead  of  a  child, 

sues  beneath  the  skin  at  the  site  of  impact 

seem  to  be  pulpified  and  remain  perfectly  soft  to  the  touch;  the  smooth  unbroken 
skull  can  usually  be  felt  over  an  area  equal  to  the  site  of  impact.  Surrounding  this 
soft  area  is  the  hardened  ring,  composed  of  tissues  between  the  skin  and  the  bone, 
into  which  serum  and  blood  have  been  effused. 

Inflaviniation  and  abscess  are  caused  by  infected  wounds,  furuncles,  erysipelas, 
caries  of  the  skull  and  suppurating  sebaceous  cysts. 

The  scalp  is  a  favorite  location  for  erysipelas;  if  not  started  primarily  by  an 
infected  wound,  the  scalp  may  be  involved  secondarily  by  extension  from  the  face. 

Caries  of  the  skull  is  often  of  syphilitic  origin. 

Abscesses  maj  occur  in  three  places: 

1.  Subcutaneous. 

2.  Subaponeurotic. 

3.  Subpericranial. 

I.  Subcutaneous  abscesses  are  usually  small  and  do  not  tend  to  spread  but 
rather  to  discharge  through  the  skin.  This  is  because  the  firm  fibrous  trabeculae 
prevent  lateral  extension.  Furuncles  are  quite  common  in  childhood;  they  are,  of 
course,  superficial  to  the  aponeurosis.  Sebaceous  cysts  are  especially  common  in 
the  scalp  and  they  sometimes  suppurate.  The  orifice  of  the  obstructed  duct  is  not 
usually  visible.  Sometimes  in  a  small  cyst  a  black  spot  on  its  surface  indicates 
the  opening  of  the  duct.  By  means  of  a  needle  or  pin  this  opening  can  be  dilated 
and  some  of  the  contents  expressed.  Of  course,  if  nothing  further  is  done  it  will 
reaccumulate.  When  these  cysts  become  inflamed  they  become  united  to  the  skin 
above  so  that  it  has  to  be  dissected  off.  If  pus  forms,  it  either  remains  localized  to 
the  cyst  or  bursts  through  the  skin  and  discharges  externally.  It  does  not  tend 
to  burrow  under  the  skin  laterally  on  account  of  the  fibrous  trabeculae  uniting  the 


APPLIED   ANATOMY. 


skin  and  aponeurosis.  The  aponeurosis  beneath  is  intact,  therefore  the  pus  does 
not  get  below  it.  The  cyst,  with  the  Hning  membrane  entire,  should  be  removed, 
otherwise  it  will  recur. 

2.  Subaponeurotic  abscesses  come  from  infected  wounds,  erysipelas,  or  caries  of 
the  bones.  It  is  not  desirable  to  close  deep  wounds  of  the  scalp  too  tightly.  Some 
suppuration  is  liable  to  occur  which,  not  finding  an  easy  escape  externally,  may 
spread  under  the  aponeurosis  if  the  wound  has  been  deep  enough  to  divide  it. 
Infection  of  wounds  is  the  most  frequent  source  of  these  abscesses,  hence  the  desira- 
bility of  providing  for  drainage  for  at  least  a  short  period.      In  erysipelas,  serous 

effusion,  which  may  become  purulent,  oc- 
curs in  the  subaponeurotic  tissue,  as  well  as 
in  the  layers  above.  It  may  sink  down- 
ward and  point  in  the  temporal,  occipital,  or 
frontal  region.  In  the  temporal  region  the 
descent  of  the  pus  may  be  limited  by  the 
attachment  of  the  lateral  expansion  of  the 
aponeurosis  to  the  zygoma.  The  attachment 
of  the  occipitalis  muscle  posteriorly  to  the 
superior  curved  line  of  the  occiput  prevents 
the  effusion  from  coming  to  the  surface  at 
that  point.  The  liquid  accumulates  low  down 
on  the  forehead  over  the  orbits,  being  pre- 
vented from  entering  by  the  attachment  of 
the  orbitotarsal  ligament,  and  tends  to  point 
close  to  the  median  line.  The  frontal  muscles 
of  the  two  sides  are  apt  to  be  slightly  sep- 
arated, leaving  a  weak  spot  just  above  the 
root  of  the  nose,  and  this  is  where  fluctua- 
tion can  most  easily  be  felt.  These  accumu- 
lations in  the  frontal,  temporal,  and  occipital 
regions  may  require  incisions  for  their  evac- 
uation and  drainage.  Suppuration  arising 
from  carious  bone  readily  perforates  the 
pericranium  and  then  infiltrates  the  loose 
subaponeurotic  tissue.  The  bones  of  the  vault  of  the  skull  are  not  infrequently 
affected  by  syphilitic  disease,  producing  caries  and  suppuration,  which  invade  the 
subaponeurotic  space. 

3.  Subpericranial  abscesses  are  comparatively  rare.  They  usually  start  from 
diseased  bone  and  spread  laterally  beneath  the  pericranial  tissue.  The  pus  may  be 
limited  to  a  single  bone  on  account  of  the  firmer  attachment  of  the  pericranium  at  the 
site  of  the  sutures.  To  avoid  breaking  into  the  subaponeurotic  space,  a  free  opening 
should  be  made  into  the  abscess  so  as  to  allow  the  pus  to  drain  externally. 


Fig.  8. — Arterial  angioma  or  cirsoid  aneurism. 


AFFECTIONS   OF   THE   BLOOD-VESSELS. 

The  arteries  or  veins  alone  may  be  affected,  or  both  may  be  invoh'ed. 

Arterial  varix  is  the  name  given  to  an  enlargement  of  a  single  artery.  It  forms 
a  swollen,  tortuous,  pulsating  mass  in  the  course  of  the  artery.  The  temporal  artery 
is  liable  to  be  so  affected,  particularly  its  anterior  branch. 

Cirsoid  ajieiirism,  or  aneurism  by  anastomosis,  is  formed  by  numerous  enlarged 
arteries.  It  is  sometimes  called  an  arterial  angioma  ox plexiforni  angioma.  The 
veins  are  also  somewhat  involved.     Pulsation  is  marked. 

Venous  angioma  is  a  tumor  formation  in  which  the  venous  blood  is  contained  in 
large  spaces,  which  are  lined  with  endothelium,  instead  of  in  normal  veins. 

Telangiectasis  or  ncevKS  is  formed  of  enlarged  capillaries.  It  is  often  called 
port  wine  mark,  mother's  mark,  etc. 

Aneurismal  varix,  or  arterioveno7is  aneurism ,  is  where  an  adjacent  artery  and 
vein  being  wounded, — as  the  temporal  artery  and  vein, — the  blood  passes  directly 
from  the  artery  into  the  vein. 


THE   SCALP.  7 

Varicose  aneurism  is  where  a  sac  intervenes  between  the  artery  and  vein,  so 
that  the  blood  passes  first  from  the  artery  into  the  sac  and  then  into  the  vein.  The 
temporal  artery  with  its  companion  vein  has  been  so  affected. 

Treatment  of  Vascular  Affections  of  the  Scalp. — Vascular  tumors  are 
usually  ligated  and  excised.  Acupressure  pins  may  be  passed  under  the  larger 
arterial  trunks,  but  the  exceedingly  free  anastomosis  renders  thorough  excision 
preferable;  even  this  is  not  seldom  unsuccessful. 


TUMORS   OF   THE   SCALP. 

Sebaceous  cysts  arise  from  obstructed  sebaceous  glands;  the  contents  consists  of 
epithelial  cells,  fat,  and  cholesterin.  They  sometimes  calcify.  They  spread  in  the 
subcutaneous  tissue,  stretching  and  raising  the  skin  above  and  causing  atrophy  of 


Fig.  9. — Sebaceous  cyst  of  scalp. 


Fig.  10. — Meningocele. 


the  hair  bulbs,  but  do  not  involve  the  epicranial  aponeurosis  below.  In  removing 
them,  if  they  have  never  been  inflamed,  they  can  readily  be  turned  out  through  a 
slit  in  the  skin.  The  subaponeurotic  space  will  not  be  opened,  therefore  their 
removal  is  not  often  followed  by  bad  results. 

Encephalocele  is  a  tumor  .formed  by  a  protrusion,  through  the  skull,  of  the 
membranes  of  the  brain,  containing  brain  matter  and  cerebrospinal  fluid. 

Meningocele,  or  a  tumor  containing  the  meninges  of  the  brain  and  cerebrospinal 
fluid,  is  more  rare  in  the  skull  than  is  the  case  when  the  spine  is  affected.  It  pro- 
trudes through  an  unossified  part  of  the  skull,  and,  according  to  Sutton,  two-thirds  of 
the  cases  occur  in  the  occipital  region,  between  the  foramen  magnum  and  torcular 
Herophili.  He  characterizes  it  as  a  hydrocele  of  the  fourth  ventricle,  and  says  that 
nine  out  of  ten  cases  die  if  operated  on.  The  next  most  frequent  seat  for  meningo- 
cele is  at  the  root  of  the  nose  (Fig.  10). 

Cephalhydrocele  is  the  name  given  to  a  pulsating  tumor  communicating  with  the 
interior  of  the  skull  through  a  traumatic  opening.     It  contains  cerebrospinal  fluid. 

Dermoid  tumors  occur  in  the  median  line  and,  according  to  Sutton,  are  most 
common  over  the  anterior  fontanelle  and  external  occipital  protuberance.  They  often 
have  a  thin  pedicle  attaching  them  to  the  dura  mater  and  may  grow  either  inside  or  out- 
side the  skull.  They  are  formed  by  an  inclusion  of  some  of  the  tissue  of  the  ectoderm 
by  the  bones  as  they  approach  from  each  side  to  ossify  and  unite  in  the  median  line. 

A  congenital  tumor  located  at  the  root  of  the  nose  is  probably  an  encephalocele; 
one  located  at  the  anterior  fontanelle  is  probably  a  dermoid;  a  tumor  in  the  occipital 
region  may  be  either,  but  a  dermoid  is  apt  to  be  higher  up  than  an  encephalocele. 


APPLIED   ANATOMY 


THE  SKULL 

The  skull  is  the  bony  framework  of  the  head.  It  is  divided  into  the  bones  of 
the  cranium  and  those  of  the  face.  The  hyoid  bone  is  usually  classified  with  the 
bones  of  the  head. 

The  cranium  consists  of  the  bones  forming  the  brain  case.  They  are  the 
occipital,  two  parietals,  the  frontal,  two  temporals,  the  sphenoid,  and  the  ethmoid. 

The  bones  of  the  face  are  fourteen  in  number,  there  being  two  single  bones 
and  six  pairs.  The  single  bones  are  the  mandible,  or  inferior  maxilla,  and  vomer  ; 
the  pairs  are  the  superior  maxilla,  malar,  nasal,  palate,  lachrymal,  and  inferior 
turbinated  bones. 

THE   SKULL   IN   CHILDHOOD. 

The  skull  of  the  infant  is  markedly  different  from  that  of  the  adult.  At  birth  the 
face  is  quite  small  and  undeveloped,  while  the  cranium  is  relatively  large.     The  frontal 

and  parietal  eminences  are  very  marked. 

^^  — vj^^,,^  The  vault  of  the  skull  is  not  entirely  os- 

^^m  ^^^  sified  and  the  sutures  are  not  completed. 

.^^Kk  .i^b^.  The  bones  of  the  base  of  the  skull 

"^^^^^  '    "^^^  originate  in  cartilage,  while  those  of  the 

vault  originate  in  membrane.   This  mem- 
A  \  ""^^^  brane  has  one  or  more  centres  of  ossi- 

M  ^  ^^11^^         fication  appearing  in  it  for  each  bone. 

^K-  ^  '^^P|k       These  centres  increase  in  size  and  finally 

^'  I  ^      meet  at  the  edges  of  the  bone,  thus  form- 

ing the  sutures.  At  the  time  of  birth  the 
sutures  are  represented  by  membrane, 
which  joins  the  adjacent  bony  edges. 

The  frontal  bone  has  two  centres  of 
ossification;  one  for  each  side.  These 
form  a  suture  in  the  median  line  of  the 
forehead  which  becomes  obliterated  in 
the  course  of  the  first  or  second  year. 
Traces  of  it  in  the  shape  of  a  groove  or 
ridge  can  sometimes  be  seen  or  felt  in  the 
adult  skull.  The  frontal  cmine7ices  are 
far  more  marked  in  childhood  than  later 
in  life  and  give  to  children  the  promi- 
nent forehead  which  is  so  characteristic. 
A  similar  peculiarity  is  seen  in  the 
parietal  bones,  the  parietal  eminences 
being  quite  prominent.  On  this  account,  they  are  often  injured  in  childbirth, 
sometimes  being  compressed  by  the  obstetrical  forceps,  and  are  frequently  the  seat  of 
hcematoma  neonatorum.  The  cranial  bones  not  being  firmly  united  allow  of  a  certain 
amount  of  play  or  even  overlapping,  thus  facilitating  the  delivery  of  the  head  at  birth. 
Fontanelles. — At  the  juncture  of  the  various  bones  are  six  spaces  called  fontan- 
elles.  Two,  the  anterior  and  posterior,  are  in  the  median  line  of  the  cranium,  and 
four,  the  two  anterolateral  and  two  posterolateral,  are  at  the  sides.  The  fontanelles 
are  situated  at  the  four  corners  of  the  parietal  bones. 

The  anterior  fontanelle  is  the  largest.  It  is  diamond-shaped  and  formed  by  the 
frontal  suture  in  front,  the  interparietal  behind,  and  the  coronal  at  each  side.  It  is  usu- 
ally closed  by  the  end  of  the  second  year,  but  may  be  delayed  until  the  fourth.  In 
rickets  and  malnutrition  the  fontanelles  remain  open  longer  than  would  otherwise 
be  the  case. 

The  posterior  fontanelle  is  formed  by  the  juncture  of  the  parietal  (sagittal)  suture 
with  the  lambdoidal  suture.  It  is  triangular  in  shape  with  the  apex  forward  between 
the  two  parietal  bones,  the  sides  passing  down,  one  to  the  right  and  the  other  to  the 
left  of  the  top  of  the  occipital  bone. 


Anterior. 


Fig.  II. — Infant's  skull,  showing  posterior  and  anterior 
fontanelles. 


THE   SKULL. 


9 


Fig.  12.- 


-Infant's  skull,  showing:  anterolateral  and  postero- 
lateral fontanel  les. 


These  fontanelles  are  of  the  greatest  importance  in  diagnosing  the  position  of 
the  head  during  labor.  If  the  examining  finger  encounters  first  a  large  diamond- 
shaped  or  four-cornered  depression  with  its  anterior  angle  more  acute  than  the  pos- 
terior, the  accoucheur  will  know  that  it  is  the  anterior  fontanelle  which  is  presenting. 
By  following  one  of  the  sutures  backward  he  will  come  to  a  triangular  or  Y-shaped 
ridge  which  will  be  recognized  from  its  shape  as  being  the  posterior  fontanelle.  He 
will  then  know  that  the  position  of  the 
head  is  occipitoposterior.  If  the  posi- 
tion is  the  more  usual  occipito-anterior 
one,  the  finger  will  first  encounter  the 
posterior  fontanelle  wiih  its  three  sutures, 
which  are  distinctly  recognizable.  On 
following  the  suture  which  leads  back- 
ward, the  four-cornered  anterior  fon- 
tanelle will  be  felt.  The  various  sutures 
constituting  the  fontanelles  can  usually 
be  distinctly  felt,  and,  as  the  presenta- 
tions are  nearly  always  occipito-anterior, 
the  fontanelle  that  will  usually  be  first 
felt  will  be  the  posterior,  and  the  sutures 
forming  it  can  readily  be  counted. 

The  antero-  2i\\<\  posterolateral  fon- 
tane//es,  located  at  the  anterior  and  pos- 
terior angles  of  the  parietal  bones,  are 
of  no  service  in  diagnosing  the  position 
of  the  head.    They  are  indistinct,  nearly 

closed,  and  thickly  covered  by  tissue.  In  injuries  to  the  skull  in  young  children 
and  infants,  we  should  not  mistake  the  fontanelles  and  lines  of  the  sutures  for 
fractures.  Fissures  extending  into  the  occipital  bone  from  the  posterolateral  fonta- 
nelles are  normal  at  birth  and  not  due  to  injury. 

Dura  Mater. — The  dura  mater  in  children  is  more  firmly  attached  to  the 
interior  of  the  skull  than  in  adults.  If,  therefore,  a  true  fracture  does  occur,  lacera- 
tion of  the  dura  is  more 
liable  to  be  produced.  This 
firm  attachment  also  pre- 
vents the  formation  of  epi- 
dural hemorrhages,  because 
the  force  of  the  blow  is  not 
sufficient  to  loosen  the  dura 
from  the  bone,  and  when 
the  middle  meningeal  artery 
is  torn,  as  Marchant  has 
pointed  out,  the  bleeding 
is  more  apt  to  be  external 
than  internal. 

Cells  and  Air-sinuses. 
— The  infant  has  the  bones 
of  the  face  so  slightly  developed  that  there  is  no  room  for  the  cavities  which  after- 
ward develop  in  them.  The  ridges  of  the  bones  also  become  more  marked  as  age 
advances.      The  young  child  has  no  superciliary  ridges. 

The  maxillary  sums,  or  antnim  of  Highmore,  and  the  mastoid  antrum  are  the  only 
cavities  that  exist  at  birth.  They  are  both  much  smaller  than  they  ultimately  become. 
The  mastoid  antrum  in  relation  to  the  size  and  age  of  the  child  is  comparatively 
large,  being  about  fixe  millimetres  in  diameter.  As  the  bone  in  the  child  is  unde- 
veloped, and  the  tympanum  lies  nearer  to  the  surface,  the  antrum  likewise  is  some- 
what higher  and  nearer  to  the  surface  than  is  the  case  in  adults.  This  should  be 
borne  in  mind  when  operating  on  the  bone  in  this  region  (Fig.  13). 

The  frontal,  ethmoidal,  and  sphenoidal  si?i7ises  appear  about  the  seventh  year, 
but  it  is  not  until  puberty  is  reached  that  they  really  begin  to  develop.     The  mastoid 


Mastoid  antrum 


External 
auditory  meatus 

Mastoid  process 


Fig.  13. — The  surface  of  the  temporal  bone  has  been   chiselled 
showing  the  relative  size  and  position  of  the  mastoid  antrum  and  external 
auditory  meatus. 


lo 


APPLIED   ANATOMY. 


Fig.  14. — Transverse  section  of  the  skull  showing  its 
variations  in  thickness  at  different  points. 


cells  likewise  appear  at  puberty  and  increase  with  age.      At  birth,  they  are  repre- 
sented by  simple  cancellous  bone. 

THE  SKULL  IN  ADULTS. 

As  the  child  grows,  the  bones  of  the  face  increase  more  rapidly  than  do  those 

of  the  vault.      The  bony  prominences  become  marked,    due  to  the  action  of  the 

various  muscles  of  mastication,  expres- 
sion, etc.,  inserted  into  them.  The 
face  is  much  larger  in  size  in  proportion 
to  the  calvarium  than  was  the  case  in 
infancy.  While  in  infancy  bone  is  prac- 
tically homogeneous,  in  late  childhood 
and  early  adult  life  cavities  begin  to 
develop  in  it. 

Outer  and  inner  tables  of  compact 
tissue  are  formed,  separated  by  diploic 
structure.  The  frontal,  ethmoidal,  and 
other  air-sinuses  are  an  exaggeration 
of  these  diploic  spaces.  They  are  lined 
with  mucous  membrane  and  communi- 
cate with  the  nasopharynx.  The  diploe 
first  begins  to  appear  about  the  age  of 

ten  years,  but  is  not  well  formed   until   early  adult  life.      It  contains  large  veins, 

called  the  diploic  veins,  which  communicate  with  the  veins  both  of  the  inside  and 

outside  of  the  skull.     In  injuries  to  the  skull 

bleeding  from  these  veins  is  rarely  trouble- 
some and  usually  stops  spontaneously. 

The  skull  is  thinner  in  the  white  than 

in  the  negro  race.     It  is  thickest  over  the 

occipital    protuberance  and    mastoid    proc- 
esses.    The  bone  is  thinnest  in  the  temporal 

and  lower  occipital  regions.     The  two  tables 

are  separated  widely  from   one  another  in 

the  region  of  the  frontal  sinuses. 

Tables. — The  inner  table  is  thinner  and 

more  brittle  than  the  outer  one,  and  in  frac- 
tures it  is  almost  always  more  extensively 

splintered  than  the  outer.     In  rare  cases  the 

outer  table  may  be  temporarily  depressed  by 

a  glancing  blow  and  spring  back  into  place 

without  showing  any  depression,  while  the 

inner  table  may  be  fractured. 

The  two  tables  are  not  exactly  parallel. 

Where  the  skull  is  thin,  as  in  the  temporal 

and    occipital   *egicns,    they   are    close    to- 
gether; where  it  is  thick,   they  are  farther 

apart.     The   outer   surface  of   the   skull  is 

comparatively  even  and  smooth.     The  inner 

surface  is  quite  uneven,  being  depressed  in 

places   to   receive    the   convolutions  of  the 

brain.    For  this  reason  it  is  necessary  to  use 

the  trephine  with  great  care,  as  it  may  cut 

through  on  one  side  of  the  circle  and  injure 

the  dura  mater  before  it  cuts  through   the 

other  part. 

The  sutures  of  the  skull  begin  to  ossify 

at  about  the  age  of  forty  years  and  continue  to  fuse  until  about  the  eightieth  year. 
Frontal   Sinuses. — The  frontal  sinuses  begin  to  develop  at  the  age  of  seven 

years,  but  do  not  increase  rapidly  in  size  until  puberty.     When  adult  age  is  reached 


Fig.  15.— Frontal  sinus  of  one  side;  the  anterior  wall 
has  been  cut  away,  exposing  its  interior. 


THE   SKULL. 


II 


they  are  well  developed.  They  may  extend  well  out  over  the  orbits,  reaching  to 
within  a  short  distance  of  the  temporal  ridge,  while  in  other  instances  they  do  not  go 
beyond  the  supra-orbital  notches.  In  height  they  may  reach  the  lower  portion  of 
the  frontal  eminences  or  may  cease  at  the  level  of  the  superciliary  ridges.  The  size 
of  the  sinus  cannot  be  judged  from  the  size  of  the  bony  prominences.     Neither  is  the 


Mastoid  antrum 

Supraineatal  spine 


Mastoid  cells 
Fig.  i6. — Surface  chipped  away  to  show  the  mastoid  antrum  and  cells,  the  latter  unusually  well  developed. 

size  nor  sex  of  the  individual  any  criterion.  In  a  small  female  we  have  seen  them  of 
considerable  size.  When  diseased  sufficiently  to  give  rise  to  symptoms,  they  will  be 
found  to  be  quite  large.  They  are  separated  from  each  other  by  a  septum,  and  if 
extensive  are  divided  into  several  pockets  or  recesses.     They  open  into  the  infundib- 

Superior  longitudinal  sinus 


Inferior  longitudinal  sinus 


Straight  sinus 
Torcular  Herophili 

Lateral  sinus 
Occipital  sinus 

Superior  petrosal  sinus 
Sigmoid  sinus 
Inferior  petrosal  sinus 
Jugular  vein        Cavernous  sinus 
Fig.  17. — The  cerebral  blood  sinuses. 

ulum,  at  the  anterior  extremity  of  the  middle  turbinated  bone  in  the  middle  meatus 
of  the  nose.  Fracture  of  the  outer  wall  of  the  sinus  not  infrequently  occurs  without 
involving  the  inner  table. 

Mastoid  Process. — The  mastoid  process  is  continous  with  the  superior  curved 
line  of  the  occiput.  It  increases  in  size  from  the  time  of  birth,  but  is  composed  of 
cancellous  tissue  until  after  the  age  of  puberty,  when  the  mastoid  cells  develop.  The 
mastoid  antrum,  a  cavity  five  millimetres  in  size  at  birth,  which  opens  into  the  upper 
posterior  portion  of  the  tympanum,  is  relatively  larger  at  birth  than  in  the  adult. 


12  APPLIED   ANATOMY. 

It  is  of  importance  in  operating  for  infection  arising  from  middle-ear  disease.  Minute 
veins  run  from  the  antrum  into  the  lateral  sinus. 

Suprameatal  Triangle. — This  triangle,  so  named  by  Macewen,  is  formed 
above  by  the  posterior  root  of  the  zygoma,  anteriorly  by  the  bony  posterior  wall  of 
the  external  auditory  meatus  and  posteriorly  by  a  line  from  the  floor  of  the  meatus 
passing  upward  and  backward  to  meet  the  first  line.  The  mastoid  antrum  is  reached 
by  operating  through  this  triangle  (see  section  on  Ear). 

Cerebral  Venous  Sinuses. — The  fibrous  membrane  which  lines  the  inte- 
rior of  the  skull  is  composed  of  two  layers  which  are  in  most  places  intimately 
united,  forming  one  single  membrane  known  as  the  dura  mater.  The  outer 
layer  is  applied  to  the  bone,  while  the  inner  layer  covers  the  brain.  In  certain 
places  these  two  layers  separate  to  form  channels  in  which  venous  blood  flows ; 
these  channels  are  called  sinuses.  In  certain  other  places  these  layers  separate  and 
enclose  some  special  structure,  as  the  Gasserian  ganglion. 

The  cerebral  sinuses  of  most  importance  are  the  siiperior  longitndinal,  the  lateral 
or  transverse,  and  the  cavernoics. 

The  superior  lotigitudi?ial  sinus  runs  in  the  median  line  from  the  foramen  caecum 
in  the  ethmoid  bone  in  front,  to  the  torcular  Herophili  behind.     As  it  passes  back- 


FiG.  i8.— Posterior  view  of  the  skull,  showing  the  relation  of  the  superior  longitudinal  sinus  and  torcular  Herophili 
to  the  median  line  and  external  occipital  protuberance. 

ward  it  inclines  more  to  the  right  side,  so  that  at  the  torcular  Herophili  the  left  side 
of  the  sinus  is  about  in  the  median  line.  This  sinus  receives  the  veins  from  the 
cortex  of  the  brain  and  also  some  from  the  diploe  of  the  bones  above  it.  A  vein 
pierces  the  upper  posterior  angle  of  each  parietal  bone  and  forms  a  communication 
between  the  superficial  veins  of  the  scalp  outside  and  the  superior  longitudinal  sinus 
within.  The  deviation  of  the  superior  longitudinal  sinus  toward  the  right,  as  it 
proceeds  posteriorly,  is  to  be  borne  in  mind  in  operating  in  this  region,  as  one  can 
approach  the  median  line  nearer  on  the  left  side  posteriorly  than  the  right,  without 
wounding  it.  In  the  parietal  region  the  Pacchionian  bodies  are  surrounded  by 
extensions  from  the  longitudinal  sinus  and  free  hemorrhage  will  ensue  if  the  bone  is 
removed  too  close  to  the  median  line. 

The  torcular  Herophili,  or  confluence  of  the  sinuses,  does  not  correspond  exactly 
to  the  external  occipital  protuberance  or  hiion  on  the  exterior  of  the  skull.  It  is 
a  little  above  and  to  the  right  of  it.  This  torcular  Herophili  is  formed  by  the  meet- 
ing of  the  longitudinal  sinus  from  above,  the  lateral,  or  transverse  sinuses  from 
the  sides,  the  straight  sinus  from  in  front  and  the  occipital  sinus  from  below. 

The  lateral  or  transverse  sinuses,  of  which  there  are  two,  pass  from  the  torcular 
Herophili  toward  each  side  in  the  tentorium  between  the  cerebrum  and  cerebellum, 
following  the  superior  curved  line  of  the  occiput  until  just  above  the  upper  posterior 
portion  of  the  mastoid  process.     They  then  bend  downward  to  within  a  centimetre  of 


THE   SKULL. 


13 


the  tip  of  the  process  and  again  curve  forward  to  end  in  the  jugular  foramen  and  be 
continued  as  the  internal  jugular  vein.  The  S-shaped  curve  which  they  make  in  this 
part  of  their  course  has  given  rise  to  the  name  sigmoid  sinus.  In  its  course  along 
the  superior  curved  line  the  sinus  rises  above  the  level  of  a  line  drawn  from  the  inion 
to  the  centre  of  the  external  auditory  meatus. 

In  operating  for  cerebellar  abscess,  care  should  be  taken  to  place  the  trephine 
opening  sufficiently  low  down  to  avoid  wounding  this  sinus.  It  is  in  great  danger  of 
being  wounded  in  operating  for  septic  conditions  involving  the  mastoid  antrum  and 
cells.  Its  distance  from  the  surface  of  the  skull  varies  in  different  individuals,  and  it 
gets  farther  from  it  as  it  descends  to  the  level  of  the  tip  of  the  mastoid  process.      It 


Cavernous  sinus 


Circular  sinus 


Superior  petrosal  sinus  ■ 

I  nferior  petrosal  sinus 


Sigmoid  sini 


Occipital  sinus 
Transverse  or  lateral  sinus 


1st — olfactory 


and — optic 

3rd — oculomotor 

4th — trochlear  (pathetic) 


5th— trigeminal   (trifacial) 

6th — abducent 

7th — facial 

8th— auditory 

9th — glossopharyngeal 

loth — vagus  (pneumogastric) 

1  ith — spinal  accessory 

12th— hypoglossal 


Superior  longitudinal  sinus 

Fig.  19. — Exit  of  cranial  nerves  and  venous  sinuses  at  the  base  of  the  skull. 


receives  the  blood  from  the  posterior  lower  portion  of  the  cerebrum  and  upper 
portion  of  the  cerebellum,  and  communicates  with  the  veins  outside  the  skull  through 
the  mastoid  and  posterior  condyloid  foramina. 

Running  along  the  upper  posterior  edge  of  the  petrous  portion  of  the  temporal 
bone,  in  the  attachment  of  the  tentorium,  is  the  superior  petrosal  sinus.  It  connects 
the  lateral  or  transverse  sinus  about  its  middle  with  the  caver^ious  sinus.  More 
deeply  situated,  and  running  from  the  cavernous  sinus  to  the  lateral  sinus,  just  as  it 
enters  the  jugular  foramen,  is  the  inferior  petrosal  sinus. 

The  petrosal  and  lateral  sinuses  are  frequently  torn  in  fractures  of  the  skull.  A 
fracture  passing  through  the  petrous  portion  of  the  temporal  bone  may  tear  the 
petrosal  sinuses,  and  hemorrhage  from  the  ear  might  come  from  this  source.  A 
fracture  through  the  posterior  cerebral  fossa  may  tear  the  lateral  sinus.  Leeches 
are  sometimes  applied  behind  the  ear  in  inflammation  of  the  brain,  with  the  idea  of 
drawing  blood  from  the  lateral  sinus  through  the  mastoid  vein. 

The  occipital  sinus  is  usually  small  and  brings  the  blood  up  from  the  region  of 
the  foramen  magnum  to  the  torcular  Herophili. 

The  straight  sinus  runs  along  the  line  of  juncture  of  the  tentorium  and  falx 
cerebri.      It  receives  the  blood  from  the  ventricles  of  the  brain  which  are  drained  by 


14  APPLIED   ANATOMY. 

the  veins  of  Galen,  and  the  blood  from  the  falx  through  the  inferior  longitudinal 
sinus.  This  latter  is  usually  very  small  and  sometimes  almost  lacking,  the  blood  in 
that  case  passing  upward  to  empty  into  the  superior  longitudinal  sinus. 

The  cavernous  sinus, — one  on  each  side, — is  a  large,  irregular  space  on  the  side 
of  the  body  of  the  sphenoid  bone.  It  runs  from  the  sphenoidal  fissure  in  front  to 
the  apex  of  the  petrous  portion  of  the  temporal  bone  behind.  In  front  it  is  continu- 
ous with  the  ophthalmic  vein,  and  receives  the  sphenoparietal  sinus  which  brings  the 
blood  from  the  diploe  ;  behind  it  communicates  with  the  superior  and  inferior  petrosal 
sinuses.  The  two  sinuses  communicate  across  the  median  line  around  the  pituitary 
body,  forming  the  circular  sinus,  and  across  the  basilar  process,  forming  what  is 
sometimes  called  the  trajisverse  sinus,  but  which  is  more  correctly  described  as  a 
plexus  of  veins. 

The  cavernous  sinus  has  embedded  in  its  outer  wall  the  third  and  fourth  nerves 
and  the  ophthalmic  branch  of  the  fifth.  Farther  below  and  to  the  outer  side  of  the 
sinus  are  the  superior  and   inferior   maxillary  or  mandibular  branches  of  the  fifth 

3rd  nerve 
4th  nerve 

Ophthalmic  branch  of  5th  nerve 
6th  nerve 


Superior  maxillary  nerve 

Inferior  maxillary  (mandibular)  nerve 


Internal  carotid  artery 


Fig.  20. — Transverse  section  of  the  right  cavernous  sinus,  showing  the  position  of  the  nerves  and 
internal  carotid  artery  (from  a  dissection). 

nerve.  Within  the  sinus  and  toward  its  lower  and  inner  portion,  is  the  internal 
carotid  artery.  It  is  surrounded  by  the  blood-current.  Between  the  carotid  artery 
and  outer  wall  of  the  sinus  runs  the  sixth  nerve,  held  in  place  by  fine,  trabecular, 
fibrous  bands  which  pass  from  side  to  side  in  the  cavity  of  the  sinus. 

The  cavernous  sinuses  are  sometimes  torn  in  fractures  of  the  base  of  the 
skull,  resulting  in  a  traumatic  communication  between  the  carotid  artery  and  the 
sinus.  The  cavernous  sinus  is  not  infrequently  torn  in  attempting  the  removal 
of  the  Gasserian  ganglion,  particularly  if  its  ophthalmic  branch  is  attacked.  Its 
interior  is  not  one  large  cavity,  but  is  subdivided  by  fibrous  septa,  which  pass 
from  side  to  side.  It  is  sometimes  the  seat  of  thrombosis  and  infection,  which 
may  reach  it  through  the  ophthalmic  vein  in  front. 

FRACTURES   OF   THE   SKULL. 

Fractures  of  the  skull  are  almost  always  produced  by  violent  contact  of  the  skull 
with  some  solid  body.  In  some  cases  the  fracture  is  produced  by  a  blow  from  a 
moving  body,  as  when  a  person  is  struck  by  a  club.  In  others,  the  skull  is  moving 
and  strikes  a  body  at  rest,  as  when  a  person  falls  and  strikes  the  head  on  a  pave- 
ment. It  is  not  necessary  to  discuss  in  detail  the  mechanism  of  fractures  of  the  skull; 
it  is  sufficient  to  state  that  nearly  all  fractures  start  from  the  point  of  impact  and 
radiate  to  distant  regions.  The  effect  of  fracturing  blows  on  the  skull  of  a  child  is 
different  from  their  eiTect  on  the  skull  of  an  adult. 

Fractures  of  the  Skull  in  Children. — A  child's  skull  is  thin  and  weak,  and 
while,  to  a  certain  extent,  fragile  is  more  flexible  than  that  of  an  adult.  It  is  on  this 
account  that  blows  are  more  liable  to  expend  their  force  locally,  at  the  point  of  impact, 
and  not  produce  fractures  at  a  distance.  Therefore,  it  follows  that  fractures  of  the 
base  are  rare  in  children  in  comparison  with  fractures  of  the  vault.  Extensive 
fissured  fractures  are  also  rare.  A  blow  will  crush  the  skull  of  a  child  at  the  point 
of  impact,  much  as  an  egg-shell  is  broken  at  one  spot  by  hitting  it  with  a  knife 
handle.      A  marked   example   of  this  was    seen   in   the  case  of  a  small   boy  who, 


THE   SKULL.  15 

while  playing,  was  struck  by  a  baseball  on  the  left  frontal  eminence.  A  distinct 
circular  depression  or  cup  was  produced  exactly  corresponding  to  the  shape  of  the 
ball.  There  were  no  symptoms  of  cerebral  concussion,  because  the  force  of  the 
blow  was  expended  on  the  bone  and  not  transmitted  to  the  brain  within.  As 
pointed  out  by  Mr.  Rickman  Godlee,  the  sutures  in  very  young  children  being  soft, 
the  transmission  of  the  force  from  one  bone  to  another  is  prevented. 

The  diploic  structure  of  the  skull  is  not  well  developed  until  adult  age,  therefore 
the  bone  is  homogeneous.  It  is  also  elastic,  and,  particularly  in  infants,  it  may  be 
dented  without  being  seriously  fractured;  these  dents  are  apt  to  disappear  and 
become  level  with  the  surrounding  bone  as  the  child  grows  older.  The  dura  mater  is 
more  adherent  in  children  and  fractures  are,  on  that  account,  more  liable  to  tear  it 
and  even  lacerate  the  brain  beneath. 

Fractures  of  the  Skull  in  Adults. — As  adult  life  is  reached  the  inner  and 
outer  tables  of  the  bones  become  separated,  leaving  the  space  between  to  be  filled 
by  the  diploic  tissue.  The  diploe  consists  of  cancellous  bone  in  the  meshes  of  which 
run  the  diploic  veins  and  capillaries.  Both  the  inner  and 
outer  tables  are  brittle,  but  the  inner  especially  so.  It  is 
also  harder  and  more  compact  than  the  outer  table.  On 
account  of  this  difference  we  find  in  cases  of  fracture  that 
the  inner  table  is  more  comminuted  than  the  outer,  so  that, 
while  the  outer  may  show  a  single  line  of  fracture,  the  inner 
table  immediately  beneath  may  be  broken  into  several  frag- 
ments. This  is  one  reason  why  trephining  is  so  frequently 
resorted  to. 

In  rare  cases  there  may  be  depression   of  the  inner       ,  F'g.  2i.-smaii  piece  of  the 

,,  .,  -'.  ^  ^      .  .     .   .      .  .        skull  showing  hairs  imprisoned 

table  with  none  of  the  outer.      A  case  of  this  kmd  occurred     in  a  linear  fracture— actual  size, 
during  our  Civil  War.     A  soldier,  while  looking  over  a  ram- 
part, was  struck  a  glancing  blow  by  a  bullet,  on  the  upper  anterior  portion  of  the 
skull.     The  outer  table  at  the  site  of  injury  was  not  at  all  depressed,  but  the  inner 
table  had  a  large  piece  broken  off,  which  injured  the  membranes. 

The  elasticity  of  the  skull  is  shown  in  cases  of  fracture  in  which  hairs  are  found 
imbedded  in  the  line  of  fracture.  Figure  21  is  from  such  a  case.  A  negro  was 
struck  on  the  head  by  a  falling  rock  and  an  extensive  longitudinal  fracture  was  pro- 
duced in  which  many  hairs  were  fastened.  About  a  centimetre  from  the  main  frac- 
ture was  a  small  fissure,  not  over  a  centimetre  long,  and  sprouting  up  out  of  it,  like 
bushes  from  the  bare  ground,  were  a  number  of  hairs.  In  such  cases  the  hairs  are 
carried  into  the  line  of  fracture  by  the  force  of  the  blow ;  the  elastic  bone  then  springs 
back  into  place  and  pinches  the  hairs,  thus  holding  them  in  place. 

The  bones  of  the  adult  skull  are  very  strong  and  firmly  fixed.  The  sutures 
begin  to  unite  at  the  age  of  forty  years  and  are  likely  to  have  disappeared  at  the  age 
of  seventy.  Even  in  young  adults  the  fibrous  tissue  between  the  bones  has  so  nearly 
disappeared  that  they  practically  act  in  transmitting  force  as  one  continuous  bone. 
For  these  reasons  slight  blows  do  not  cause  fractures.  It  takes  a  very  heavy  blow 
usually  to  cause  a  fracture  and  the  force  is  so  great  that  shock  or  concussion  of  the 
brain  with  disturbance  of  its  functions  is  a  common  symptom. 

The  force  of  the  blow  is  expended  first  at  the  point  of  impact,  and  if  a  fracture 
occurs  it  usually  starts  there.  From  that  point  it  radiates  to  other  portions  of  the 
skull,  so  that  fractures  of  the  vault  frequently  extend  to  the  base.  The  course 
pursued  by  the  fracture  has  been  formulated  into  a  law  by  Aran  ;  that  they  take  a 
straight  line  from  the  point  of  impact  on  the  vault  to  the  base  of  the  skull,  and  are 
not  deflected  by  the  sutures. 

Charles  Phelps  ("Traumatic  Injuries  of  the  Brain")  found  that  in  127  cases  of 
fracture  of  the  base  of  the  skull,  12  implicated  the  base  only.  So  that,  if  we  are  able 
to  say  that  there  is  a  fracture  of  the  base  of  the  skull,  there  are  over  10  chances  to 
one  of  its  extending  up  into  the  vault.  In  only  two  were  the  fractures  more  than  a 
slight  fissure ;  so  that  in  a  marked  fracture  of  the  base  there  would  be  63  chances  to 
one  of  its  extending  into  the  vault.  Also,  from  Aran's  law,  we  see  that,  if  we  diag- 
nose a  fracture  through  the  middle  ear,  we  may  be  pretty  sure  that  the  force  was 
applied  directly  above,  and  be  led  to  trephine  accordingly. 


i6 


APPLIED   ANATOMY. 


A  man  fell  from  an  electric  light  pole  and  was  brought  to  the  hospital  with  bleed- 
ing from  the  ear  and  other  symptoms  of  fracture  of  the  skull.  He  became  wildly- 
delirious,  and,  feeling  sure  that  the  fracture  of  the  base  was  an  extension  from  the 
vault,  although  no  depression  could  be  felt,  he  was  trephined  above  the  external 
auditory  meatus  and  a  large  epidural  effusion  of  blood  evacuated.  He  recovered 
and  resumed  his  work.  In  this  case,  as  soon  as  the  bone  was  exposed,  a  thin  line 
of  fracture  was  .seen  running  down  to  the  base  in  the  region  of  the  external  ear. 

Fractures  by  Contrecoup  or  Counter  Stroke. —  Fractures  by  counter 
stroke  are  now  regarded  as  of  much  less  frequent  occurrence  than  formerly.  Charles 
Phelps  found  in  147  cases  of  fracture  of  the  base  of  the  skull  12  which  had  not 
extended  from  the  vault.  In  these,  the  force  had  been  applied  to  the  parietal  region 
in  six,  and  in  five  to  the  occiput;  most  of  the  resulting  fractures  were  in  the  region 


Or!  >ital  plate  of  frontal 


Anterior  cerebral  fossa' 


Foramen  rotuntium 


Middle  cerebral  fossa 


Posterior  cerebral  fossa 


Cribriform  plate  of  ethmoid 


Lesser  winj^  of  sphenoid 
Optic  foramen 
Anterior  clinoid  process 
Greater  wing  of  sphenoid 

Sella  turcica 

Post,  clinoid  process 

—  Foramen  ovale 
_  Foramen  spinosum 

—  Body  of  sphenoid 
Petrous  portion  of  temijoral 
Body  of  occipital 

Internal  auditory  meatus 


%|to4    s^^^VT]--^  Jugular  or  post,  lacerated 
"^^  ~z!^^m  f  J  foramen 

Sigmoid  sinus 


Torcular  Herophili 


Fig.  22.— Interior  view  of  the  base  of  the  skull,  showing  the  parts  most  liable  to  be  involved  in  fractures. 


of  the  orbit.  Only  two  of  the  twelve  cases  were  serious  fractures,  the  remaining  ten 
being  slight  fissures,  which  produced  no  symptoms. 

Hemorrhage  in  Fractures  of  the  Skull. — Hemorrhage  is  a  frequent  and  most 
valuable  symptom  in  diagnosing  the  existence  of  fracture  and  in  determining  its  location. 

Fracture  through  the  anterior  cerebral  fossa  may  open  the  frontal,  ethmoidal,  or 
sphenoidal  cells  and  cause  bleeding  from  the  nose  and  mouth. 

A  fracture  through  the  roof  of  the  orbit  causes  bleeding  into  the  orbital  cavity;  the 
blood  works  its  way  forward  and  makes  its  appearance  under  the  conjunctiva  of  the 
ball  of  the  eye.  Its  progress  forward  toward  the  lids  is  blocked  by  the  orbitotarsal 
ligaments,  and  it  therefore  works  its  way  downward  to  the  bulbar  conjunctiva,  under 
which  it  advances  to  the  edge  of  the  cornea.  The  ordinary  ecchymosis  of  the  lids  and 
cellular  tissue  around  the  eye  is  usually  due  to  a  rupture  of  the  vessels  of  the  subcuta- 
neous tissue  by  a  blow  from  the  outside,  and  not  to  a  fracture  of  the  base  of  the  skull. 


THE    SKULL. 


17 


Fracture  through  the  middle  cerebral  fossa  may  pass  through  the  body  of  the 
sphenoid  or  basilar  process  of  the  occipital  bone  and  cause  bleeding  into  the  mouth. 
It  may  also  cause  an  accumulation  of  blood  behind  the  posterior  wall  of  the  pharynx, 
pushing  it  forward.      When  it  passes  through  the  petrous  portion  of  the  temporal 


Anterior  branch 
piercing  the  bone 


Posterior  branch 


Posterior  meningeal 
from  vertebral 

Middle  meningeal 

Fig.  23.— Middle  and  posterior  meningeal  arteries  supplying  the  interior  of  the  skull. 

bone,  as  is  frequently  the  case,  it  may  involve  the  external  auditory  meatus  and 
bleeding  from  the  ear  will  result. 

Fractures  through  the  posterior  cerebral  fossa  may  cause  bleeding  into  the  struc- 
tures of  the  back  of  the  neck.     This  is  not  common. 

Middle  Meningeal  Hc7norrhage.  —  Bleeding  from  the  middle  meningeal  artery, 
epi-  or  extradural  hemorrhage,  occurs  in  those  fractures  which  pass  through  the  region 


External  angular  process 


Anterior  branch  of 
middle  meningeal 


Posterior  branches  of 
middle  meningeal 


Fig.  24.— Points  of  trephining  for  hemorrhage  from  the  middle  meningeal  artery.     The  course  of  the  artery  has  been 

marked  on  the  outer  surface  of  the  skull. 

of  the  pterion  This  point  is  the  junction  of  the  coronal  and  sphenoparietal  sutures, 
about  4  cm.  ( i  ^  in. )  behind  and  slightly  above  the  external  angular  process  of  the 
frontal  bone.  The  middle  meningeal  artery  comes  up  through  the  foramen  spinosum 
and   then  goes  forward,    upward,  and  outward  to  the  lower  anterior  angle  of  the 


i8  APPLIED    ANATOMY. 

parietal  bone.  It  sends  branches  forward  to  the  frontal  region  and  backward  to  the 
parietal  and  temporal  regions.  During  two  to  three  centimetres  of  its  course,  at  the 
pterion,  it  passes  entirely  through  bone,  and  therefore  if  a  fracture  occurs  at  this 
point  it  must  of  necessity  tear  the  artery.  The  posterior  branches  are  not  regular  in 
their  course,  one  passing  backward,  low  down,  parallel  to  the  zygoma,  and  another 
higher  up  in  the  direction  of  the  parietal  eminence.  The  branches  of  the  meningeal 
artery  nourish  the  bone  as  well  as  the  dura,  therefore  if  the  dura  is  loosened  from 
the  bone  hemorrhage  from  these  branches  occurs.  The  most  frequent  site  of  middle 
meningeal  hemorrhage  is  in  the  region  of  the  pterion  or  temple. 

In  trephining  for  it,  the  centre  of  the  trephine  is  to  be  placed  on  an  average  of 
4  cm.  ( I  ^  in. )  behind  the  external  angular  process  of  the  frontal  bone,  and  on  a 
level  with  the  upper  edge  of  the  orbit  or  4.5  cm.  (i^  in.)  above  the  zygoma.  If 
the  artery  is  not  sufficiently  exposed  more  bone  is  to  be  removed  by  the  rongeur 


ist — olfectory 


and — optic 

3rd — oculomotor 

4th— trochlear  (pathetic) 


5th — trigeminal  (trifacial) 
6th— abducent 

7th— facial 

8th — auditory 

9th — glossopharyngeal 

loth— vagus  (pneumogastrlc) 

nth — spinal  accessory 

12th — hypoglossal 


Fig.  25. — Exit  of  cranial  nerves  at  the  base  of  the  skull. 

forceps.  It  is  in  this  region  that  epidural  hemorrhages  are  apt  to  be  extensive, 
because  the  vessels  torn  are  the  largest;  but  epidural  hemorrhage  can  also  occur  in 
the  frontal  region  from  the  anterior  branches  and  in  the  parietal  from  the  posterior. 

Trephining  for  bleeding  from  the  posterior  branch  of  the  middle  meningeal 
artery  is  somewhat  uncertain.  In  some  cases  the  artery  runs  low  down,  about  2  cm. 
(4/5  in.)  above  the  zygoma  and  parallel  to  it.  In  other  cases  it  runs  upward  and 
backward  toward  the  parietal  eminence.  The  trephine  may  be  placed  as  high  up 
as  for  the  anterior  branch  of  the  middle  meningeal  artery,  4.5  cm.  (i^  in.),  and 
5  cm.  (2  in.)  farther  back.  This  will  be  below  and  anterior  to  the  parietal  eminence 
and  about  midway  on  a  line  joining  the  parietal  eminence  and  external  auditory 
meatus.  After  the  button  of  bone  has  been  removed,  additional  bone  may  be  cut 
away  with  the  rongeur  forceps  until  access  can  be  had  to  the  bleeding  point  (see 
page  23  for  a  case  of  rupture  without  fracture). 

Rupture  of  the  large  venous  sinuses  and  of  the  small  vessels  passing  between  the 
bone  and  .dura  also  contribute  to  the  formation  of  the  clot.     Owing  to  the  firmer 


THE    SKULL. 


19 


attachment  of  the  dura  mater  in  children,  the  meningeal  arteries  are  more  liable  to 
be  torn  and  cause  hemorrhage  than  is  the  case  in  adults.  For  the  same  reason  the 
blood  pressure  is  not  sufficient  to  dissect  the  dura  from  the  skull,  therefore  epidural 
clots  are  rare.  If  there  is  a  fracture,  blood  may  collect  beneath  the  scalp,  and  if  an 
external  wound  exists,  the  blood  will  find  an  exit  through  it. 

Bleeding  from  the  Venous  Sinuses. —  Bleeding  may  occur  from  the  sinuses  of  the 
base  as  well  as  from  those  of  the  vault.  In  severe  injuries  of  the  vault  detached  frag- 
ments frequently  penetrate  the  superior  longitudinal  and  lateral  sinuses.  In  these 
cases  profuse  bleeding  occurs  as  soon  as  attempts  are  made  to  remove  the  loose  pieces 
of  bone,  and  it  is  necessary  to  use  a  packing  of  gauze  to  control  it.  Fractures  passing 
through  the  petrous  portion  of  the  temporal  bone  wound  the  petrosal  sinus  and 
this  no  doubt  contributes  to  the  blood  which  flows  from  the  ear. 

Emphysema  is  most  likely  to  occur  if  the  frontal  air  sinuses  are  involved,  partic- 
ularly if  the  patient  blows  his  nose  in  the 
attempt  to  relieve  it  of  blood  clots.     Em- 
physema is  not  so  liable  to  occur  in  cases 
of  fracture  involving  the  mastoid  cells. 

Cerebrospinal  fluid  may  escape  when- 
ever the  meninges  are  torn  and  the  sub- 
arachnoid space  is  opened.  It  is  most  fre- 
quently seen  in  the  fractures  involving  the 
middle  fossa  and  passing  through  the  in- 
ternal auditory  meatus.  The  meninges  are 
prolonged  into  the  internal  meatus,  and  the 
clear  fluid  is  not  infrequently  seen  coming 
from  the  ear  of  the  injured  side.  Although 
the  normal  amount  of  cerebrospinal  fluid 
is  only  about  two  ounces,  much  greater 
quantities  can  escape.  A  serous  discharge, 
perhaps  of  several  ounces,  is  indicative  of 
a  rupture  into  the  subarachnoid  space. 

Injuries  to  Nerves  in  Fracture 
of  the  SkulL — The  nerves  most  often 
disturbed  in  injuries  of  the  skull  are  the 
first,  second,  third,  seventh,  and  eighth. 

The  first  or  olfactory  nerve  may  be 
injured  directly  in  the  line  of  fracture,  or 

by  concussion.  I  have  had  under  my  care  two  such  cases  in  women  who  struck  the 
occiput  on  an  asphalt  pavement  in  getting  off  backward  from  a  moving  trolley  car. 
These  patients  left  the  hospital  after  several  weeks  with  the  sense  of  smell  still  lacking. 

Injuries  to  the  second  or  optic  nerve  are  apt  to  be  accompanied  by  such  severe 
injuries  to  other  parts  as  to  cause  the  death  of  the  patient  before  the  loss  of  sight  is 
discovered.  If  the  optic  nerve  is  injured  at  the  optic  foramen,  there  may  be  impair- 
ment of  sight  without  any  intra-ocular  changes  to  be  seen  with  the  ophthalmoscope. 
Inside  of  two  weeks,  however,  the  pinkish  color  of  the  disk  gives  way  to  the  gray-white 
color  of  atrophy,  and  this  progresses  until  complete.  The  nerve  never  resumes  its 
functions  and  the  patient  remains  blind. 

Injury  of  the  third  or  oculomotor  nerve  has  also  come  under  my  notice.  In  this 
the  pupil  of  the  affected  eye  is  moderately  dilated  and  does  not  respond  to  light. 
The  ciliary  muscle  is  supplied  by  the  third  nerve,  as  well  as  the  circular  fibres  of  the 
iris,  so  that  the  accommodation  is  paralyzed  and,  if  the  eye  has  been  normal  in  its 
refraction,  the  patient  will  be  unable  to  read  or  see  objects  clearly  at  close  distances. 
The  extrinsic  muscles  of  the  eye,  with  the  exception  of  the  superior  oblique  and 
external  rectus,  are  also  supplied  by  this  nerve  and  the  eye  is  therefore  pulled  outward 
and  slightly  downward,  and  diplopia,  or  double  vision,  may  be  produced.  The  patient 
is  unable  to  move  the  eye  either  upward,  inward,  or  downward.  The  levator  palpe- 
brae  muscle  is  also  paralyzed  and  there  is  ptosis  or  drooping  of  the  upper  lid.  The 
orbicularis  palpebrarum  muscle,  being  supplied  by  the  seventh  nerve,  has  its  func- 
tions unimpaired,  and  the  eyelids  can  be  closed. 


Fig.  26.- 


-Paralysis  of  the  facial  nerve  from  fracture 
of  base  of  skull  (author's  case). 


20  APPLIED   ANATOMY. 

The  fourth  or  paJietic  Jierve  is  almost  never  injured.  It  supplies  the  superior 
oblique  muscle,  which  turns  the  eyeball  down  and  slightly  outward.  Paralysis  of  it 
causes  diplopia,  with  the  image  of  the  injured  eye  below  that  of  the  sound  eye  and 
tilted  to  the  right,  if  the  right  eye  is  affected,  and  to  the  left,  if  the  left  is  affected. 

T\\ejifth  or  trifacial  nerve  is  very  rarely  injured.  If  it  is  completely  paralyzed 
there  will  be  loss  of  motion  in  the  muscles  of  mastication  and  loss  of  sensation  over 
the  side  of  the  face,  of  one-half  of  the  interior  of  the  mouth,  of  the  side  and  front  of 
the  tongue,  and  of  the  eye. 

The  sixth  or  abduceiit  nerve  supplies  the  external  rectus  muscle  of  the  eye,  and 
if  paralyzed  causes  internal  strabismus,  the  eye  looking  inward.  While  more  often 
paralyzed  than  the  fourth  and  fifth,  it  is  not  so  frequently  paralyzed  as  are  the  two 
following  nerves. 

The  seventh  ox  facial  nerve  is  the  one  most  frequently  injured  in  fractures  of  the 
skull.  It  enters  the  internal  auditory  meatus  with  the  auditory  nerve,  being  above 
it.  Reaching  the  end  of  the  meatus  internus,  it  enters  the  canal  of  Fallopius  and 
emerges  from  the  temporal  bone  at  the  stylomastoid  foramen.  When  paralyzed,  the 
face  on  that  side  remains  motionless,  the  eye  cannot  be  closed,  and  food  accumulates 
between  the  teeth  and  cheek.  The  corner  of  the  mouth  is  drawn  to  the  opposite 
side  when  the  muscles  of  the  face  are  contracted. 

The  internal  auditory  meatus  contains  a  prolongation  of  the  dura  mater  and 
arachnoid,  so  that  a  fracture  through  it  would  open  the  subarachnoid  space  and  allow 
the  cerebrospinal  fluid  to  escape.  In  these  cases  there  is  also  usually  bleeding  from 
the  ear.  Escape  of  cerebrospinal  fluid  is  to  be  distinguished  from  a  flow  of  serum  by 
its  greater  quantity,  sometimes  many  ounces  escaping. 

The  eighth  or  auditory  nerve  is  injured  with  moderate  frequency,  but  perhaps 
hardly  so  often  as  supposed,  for  the  deafness  which  sometimes  follows  injuries  to  the 
head  may  not  be  caused  by  an  injury  to  the  auditory  nerve  itself,  but  is  rather  due  to 
the  injury  done  by  concussion  of  the  brain  in  the  region  of  the  first  temporal  con- 
volution, or  possibly  to  the  tympanum.  The  eighth  nerve  is  embraced  in  the  same 
extension  of  the  meninges  into  the  internal  meatus  as  is  the  seventh,  and  injuries  to  it 
may  also  be  accompanied  with  loss  of  cerebrospinal  fluid.  The  seventh  and  eighth 
are  said  to  be  more  often  paralyzed  than  any  of  the  other  nerves. 

Injuries  to  the  remaining  four  nerves  —  the  glossopharyngeal,  vagus,  spinal 
accessory,  and  hypoglossal — have  been  observed  too  rarely  to  require  any  extensive 
attention  here. 

THE  MENINGES. 

The  meninges  of  the  brain  consist  of  three  separate  coverings:  the  outer  being 
the  dura  mater,  the  middle  the  arachnoid,  and  the  inner  the  pia  mater. 

The  dura  mater  or  fibrous  covering  of  the  brain  is  tough  and  strong  and 
intended  to  protect  it.  Injuries  of  the  skull  without  a  laceration  of  this  membrane 
are  much  less  serious  than  when  it  is  involved.  When  it  is  torn,  not  only  is  the 
brain  beneath  likely  to  be  injured,  but  an  opportunity  is  given  for  infection  to  enter 
and  affect  the  brain  itself  and  even  produce  a  hernia  cerebri  or  hernial  protrusion  of 
brain  matter  through  the  rent. 

The  dura  mater  is  composed  of  two  layers,  the  outer  one  acting  as  a  periosteum 
to  the  bones.  The  two  layers  are  in  most  places  closely  united,  but  at  others  they 
separate  and  form  sinuses  or  canals,  connected  with  the  veins  and  carrying  venous 
blood.  They^/x  cerebri  {Y\^.  27)  which  is  the  fibrous  partition  separating  the  hemi- 
spheres of  the  brain  from  one  another,  as  well  as  the  tentoriiun,  which  separates  the 
cerebrum  from  the  cerebellum,  is  formed  by  the  inner  layer  of  the  dura  mater  project- 
ing inward  and  forming  a  partition.  On  the  floor  of  the  skull,  the  dura  mater  accom- 
panies the  nerves  and  gives  them  a  sheath.  The  Gasserian  ganglion  of  the  fifth 
nerve  is  held  in  a  pocket  formed  by  the  separation  of  the  two  layers  of  the  dura  mater. 

The  cerebral  blood  sinuses  have  already  been  considered.      The  dura  is  nour- 
ished by  the  meningeal  arteries ;  bleeding  from  these  has  already  been  alluded  to  . 
(page  17).     Thin  fibres  of  the  dura  pass  to  the  bone,  also  branches  of  the  meningeal 
arteries  and  veins  pass  to  the  inner  table  and  diploe:  these  all  serve  to  fasten  the 


THE   MENINGES. 


21 


dura  to  the  skull.  This  attachment  is  firmest  on  the  base  of  the  skull.  On  the  vault, 
after  an  opening  has  been  made  through  the  skull  by  a  trephine,  the  dura  can  be 
readily  separated  from  the  bone  by  means  of  a  thin,  flat,  steel  spatula.  On  account  of 
the  small  size  of  the  vessels  passing  from  the  dura  to  the  bone,  this  procedure  is  not 
usually  accompanied  by  much  hemorrhage.  In  separating  the  dura  from  the  base  ot 
the  skull,  as  is  done  in  operations  on  the  Gasserian  ganglion,  the  bleeding  from  this 
source  is  often  quite  free.  The  dura  is  liable  to  be  torn  in  lifting  it  from  the  bone 
if  the  greatest  care  is  not  exercised. 

The  middle  meningeal  artery,  at  a  distance  of  4  cm.  (i}4  in. )  posterior  to  the 
angular  process  of  the  frontal  bone  and  about  the  same  above  the  zygoma,  usually 
passes  within  the  bone  for  a  distance  of  i  01  2  cm.  Therefore,  in  operating  in  the 
temporal  region,  if  the  dura  is  detached  the  vessel  will  be  torn  and  free  bleeding  will 


Fig.  27. — Vault  of  the  skull  opened  and  brain  removed,  showing   the  lalx  cerebri  and  tentorium. 


follow.  The  vessel  is  liable  to  be  torn  in  endeavoring  to  remove  bony  fragments  in 
fractures  of  this  region.  The  dura  is  also  more  firmly  attached  in  the  median  line; 
and  on  each  side  of  the  median  line  are  the  depressions  in  the  parietal  bone  which 
lodge  the  Pacchionian  bodies.  The  largest  are  usually  located  at  a  distance  of  from 
2  to  5  cm.  posterior  to  a  line  drawn  across  the  skull  from  one  external  auditory 
meatus  to  the  other.  They  are  prolongations  from  the  arachnoid  and  are  surrounded 
by  blood  from  the  longitudinal  sinus. 

The  Arachnoid — also  called  Arachnopia  or  Parietal  Layer  of  the  Pia. 
— The  arachnoid  is  a  thin  fibrous  membrane,  which  passes  over  the  convolutions  of 
the  brain  and  does  not  dip  into  the  sulci  between.  It  is  more  marked  on  the  base 
than  on  the  convexity  of  the  brain.  It  is  not  attached  to  the  dura  above,  and  this 
subdural  space,  while  moist,  contains  little  or  no  free  fluid.  Hemorrhages  do  not 
occur  into  this  space  unless  the  membranes  are  torn,  because  the  bleeding  from  the 
vessels  of  the  dura  is  always  epidural  and  the  arachnoid  derives  its  nourishment  from 
the  pia  mater  below,  so  that  hemorrhages  start  beneath  the  arachnoid,  but  may  rupture 
through  the  arachnoid  into  the  subdural  space.     From  its  under  surface,  fibrils  of  loose 


22  APPLIED   ANATOMY. 

tissue  pass  to  the  pia  mater;  the  space  between  the  fibrous  layer  of  the  arachnoid  above 
and  the  pia  mater  and  convolutions  of  the  brain  below  is  called  the  siibarachnoid 
space.  This  is  a  lymph  space  and  contains  the  cerebrospinal  fiuid.  This  fluid  is 
normally  about  60  c.c.  (2  ounces)  in  quantity,  but  in  injuries  to  the  brain  in  which 
the  subarachnoid  space  is  opened,  the  fluid  is  secreted  and  discharged  very  rapidly. 

As  has  already  been  mentioned,  the  arachnoid  sends  a  prolongation  into  the 
internal  auditory  meatus,  hence  a  fracture  through  it  would  open  the  subarachnoid 
space.  This  space  communicates  with  the  ventricles  of  the  brain  through  three 
openings  in  the  pia  mater  at  the  lower  back  portion  of  the  roof  of  the  fourth  ventricle; 
these  are  called  the  foramina  of  Mage7idie,  Key,  and  Retzms.  The  cerebrospinal 
fluid  extends  down  the  spinal  canal  and  can  be  removed  by  tapping  with  a  trochar,  as 
is  practised  in  the  lumbar  region. 

The  Pia  Mater. —  The  net-work  of  vessels,  with  their  supporting  membrane, 
which  covers  the  convolutions  of  the  brain,  forms  the  pia  mater.  The  fibrils  of  con- 
nective tissue  supporting  the  vessels  are  attached  to  the  fibrous  layer  of  the  arachnoid 
above,  so  that  the  pia  and  arachnoid  are  in  reality  continuous  structures.  The  spaces 
between  these  fibrils  are  often  quite  large  and  communicate  with  each  other,  forming 
the  subarachnoid  space.  The  lower  portions  of  these  fibrils  are  united  and  form  a 
basement  membrane  which  lies  directly  on  the  convolutions  of  the  brain  and  dips  into 
the  sulci.  The  blood-vessels  are  intimately  connected  with  this  lower  pial  membrane 
and  not  with  the  arachnoid  above.  These  vessels  penetrate  into  the  substance  of  the 
brain,  carrying  with  them  a  covering  or  sheath  of  pia  mater.  This  is  called  the/'^r/- 
vascular  lymph  sheath  and,  of  course,  communicates  with  the  subarachnoid  space 
above.  These  vessels  nourish  the  brain.  The  perivascular  lymph  sheaths  are  also 
said  to  form  capsules  around  the  great  pyramidal  and  large  glial  cells  of  the  cortex. 

AFFECTIONS  OF  THE  MEMBRANES  OF  THE  BRAIN. 

Both  the  dura  mater  and  the  pia  mater  are  subject  to  inflammation  and  hemor- 
rhages. The  arachnoid  being  practically  a  part  of  the  pia  mater  is  involved  in  its 
diseases,  so  that  no  mention  is  made  of  it  as  being  separately  affected. 

Inflammation  of  the  Dura  Mater;  Pachymeningitis. — The  outer  surface 
or  inner  surface  of  the  dura  may  be  involved,  constituting  pachymeningitis  externa 
or  interna. 

Pachymeningitis  Externa.  —  The  external  surface  is  most  often  affected  by 
injuries  from  without,  or  by  extension  of  diseases  from  the  adjoining  bone.  In  cases 
of  fracture  the  inflammation  which  accompanies  healing  frequently  causes  the  dura 
to  become  densely  adherent  to  the  overlying  skull.  This  is  noticed  particularly  when 
trephining  operations  are  performed  for  the  relief  of  focal  or  Jacksonian  epilepsy. 
Should  the  fracture  be  compound  or  open,  the  occurrence  of  sepsis  will  tend  to 
involve  the  adjacent  dura  mater.  The  same  occurs  in  cases  of  necrosis.  Syphilitic 
disease  of  the  bones  is  most  apt  to  affect  the  vault  of  the  skull,  while  the  dura 
towards  the  sides  and  base  is  most  often  involved  by  suppurative  ear  disease.  The 
dura  also  becomes  involved  in  tumors  and  gummata. 

Inflammation  of  the  dura  is  not  apt  to  be  a  marked  disease.  It  is  a  very  dense 
membrane  with  few  blood-vessels,  therefore  it  is  quite  resistant  to  inflammatory  proc- 
esses. It  acts  as  a  barrier  to  the  farther  extension  of  an  inflammation  rather  than 
as  a  carrier.  Therefore  w^e  see  epidural  collections  of  pus  existing  for  a  considerable 
time  without  brain  symptoms  super\'ening. 

The  dura  mater  contains  the  large  cerebral  venous  sinuses,  and  when  the  inflam- 
matory process  occurs  in  those  regions,  the  sinuses  become  inflamed  and  thrombosis  or 
clotting  occurs.  The  clot  becoming  infected  breaks  down,  the  pus  and  debris  pour  into 
the  general  circulation,  and  general  septicaemia,  and  even  death,  is  caused.  This  is  most 
liable  to  occur  in  the  region  of  the  ear,  where  the  infection  is  apt  to  reach  and  involve 
the  lateral  (transverse)  sinus.     Infection  of  the  longitudinal  sinus  is  much  more  rare. 

Pachyme?iingitis  interyia  is  an  inflammation  of  the  inner  surface  of  the  dura.  It 
occurs,  to  a  certain  extent,  in  cases  of  gumma  or  other  new  growths  involving  the  inner 
surface  of  the  dura  or  extending  from  the  pia  mater  below.  The  name  pachymeningitis 
interna,  also  called  haemorrhagica,  is  usually  restricted  to  a  chronic  inflammation  of 


THE   iMENINGES. 


23 


le  inner  surface  of  the  dura,  with  the  formation  of  one  or  more  hemorrhagic  mem- 
branous layers.  Adhesions  to  the  pia  do  not  occur.  The  disease  has  been  seen  in 
purpuric  and  infectious  diseases,  as  well  as  in  alcoholic  and  demented  individuals. 

Dural  Hemorrhage. — Hemorrhage  arising  from  injury  to  the  dura  through 
fracture  of  the  skull  has  already  been  discussed  (see  page  18).  Epidural  hemorrhage 
may,  however,  occur  from  an  injury  to  the  skull  and  detach  the  membrane  from 
the  bone  without  a  fracture  being  present.  The  possibility  of  this  occurring  is  proved 
by  the  remarkable  case  reported  by  Dr.  J.  S.  Horsley  {New  York  Med.  Joiir.,  Feb. 
9,  190 1).  A  man  was  struck  on  the  head  with  a  wooden  club.  He  was  momen- 
tarily stunned,  but  soon  recovered  and  felt  perfectly  well.  An  hour  and  a  half  later  he 
became  drowsy,  and  in  a  few  hours  was  in  a  state  of  stupor.  The  right  side  of  the 
body  and  face  was  paralyzed,  and  the  left  arm  and  leg  were  in  constant  jerking  con- 
vulsions. He  was  trephined  over  the  left  parietal  eminence  and  four  to  six  ounces 
of  blood  clot  removed.  There  w'as  no  evidence  of  fracture  or  wound  of  the  dura. 
Recovery  was  prompt.      There  have  also  been  other  recorded  cases. 

In  operations  involving  the  separation  of  the  dura  from  the  bone,  bleeding  may 
be  quite  free.  This  comes  from  rupture  of  the  veins  passing  from  the  bone  to  the 
dura,  and  sometimes  from  the  rupture  of  a  vein  passing  over  or  in  the  dura  itself. 

Subdural  hemorrhages  always  originate  from  the  pia  mater. 

Inflammation  of  the  Pia  Mater;  Meningitis. —  This,  when  not  of  a  tuber- 
culous character  is  called  leptomeningitis.  It  is  commonly  known  as  inflammation  of 
the  brain,  or  meningitis.  The  pia  mater  of  the  brain  being  directly  continuous  with 
that  of  the  spinal  cord,  inflammations  of  the  former  extend  to  and  involve  the  latter  in 
about  one-third  of  the  cases.      The  disease  is  then  called  cerebrospinal  meningitis. 

Infection  is  the  usual  cause  of  leptomeningitis.  Direct  injury  to  the  membranes 
and  their  bony  envelopes  may  cause  it,  but  it  occurs  usually  through  some  secondary 
avenue  of  infection.  Thus,  it  may  follow  fractures  opening  into  the  mouth,  nose, 
the  various  accessory  bony  sinuses,  ear,  etc.  The  infection  may,  however,  not  be 
traumatic,  but  occur  through  the  blood,  following  or  accompanying  the  various 
infectious  diseases.  Owing  to  the  fact  of  the  pia  lying  on  the  brain  substance,  and 
its  vessels  with  their  perivascular  sheaths  penetrating  it,  the  disease  naturally  tends 
to  involve  the  brain,  if  it  is  very  severe  or  long  standing.  If  such  is  the  case,  the 
affection  is  called  cerebritis  or  encephalitis. 

The  inflammation  may  be  serous,  plastic,  or  even  purulent.  The  pia  mater  being 
continuous  with  the  choroid  plexuses,  the  ventricles  may  be  dilated  by  the  increased 
fluid.  The  infection  may  follow  the  vessels  into  the  brain  and  produce  brain  abscess. 
The  efifusion  being  often  localized  at  the  base  of  the  brain  interferes  with  the  functions 
of  the  cerebral  nerves.  The  first,  or  olfactory,  is  comparatively  rarely  affected.  The 
optic,  or  second,  is  more  often  so,  producing  intolerance  of  light.  There  may  be 
choked  disk,  and  I  have  even  seen  a  case  in  which  there  was  total  blindness  without 
any  change  being  visible  in  the  nerve  by  means  of  ophthalmoscopy.  In  this  case 
atrophy  of  the  disk  soon  followed.  The  third,  or  motor  oculi,  according  to  Church 
and  Peterson,  is  almost  always  affected.  This  would  be  shown  by  strabismus,  diplopia, 
and  changes  in  the  pupil.  Facial  paralysis,  from  implication  of  the  seventh  nerve,  is 
sometimes  seen,  and  the  auditory,  or  eighth,  may  also  be  affected.  Involvement  of 
the  hypoglossal  or  twelfth  nerve,  will  be  shown  by  de\'iation  of  the  tongue.  The 
origin  of  the  cranial  nerves  from  the  base  of  the  brain  is  shown  in  Fig.  28. 

Tuberculous  Meningitis. — In  this  form  of  meningitis  the  infection  comes  through 
the  blood,  and  the  tuberculous  lesions  follow  the  vessels.  They  are  most  marked  on 
the  base  of  the  brain,  involving  the  circle  of  Willis  and  the  Sylvian  fissure.  The 
infection  follows  the  vessels  of  the  pia  mater  through  the  transverse  fissure  into  the 
ventricles.  The  effusion  accumulating  in  the  ventricles  has  given  rise  to  the  name 
acute  hydrocephalics.  It  also  follows  the  perivascular  sheaths  of  the  smaller  vessels 
into  the  brain  substance,  producing  a  cerebritis;  thus  it  is  seen  how  a  knowledge  of 
the  circulation  of  the  brain  explains  the  location  of  the  lesions. 

The  exudate  involving  the  nerves  of  the  base  of  the  brain  produces  correspond- 
ing symptoms  by  interfering  with  their  function. 

Pial  Hemorrhage. —  Meningeal  hemorrhage  may  be  either  subarachnoid  or 
subdural.      If  the  hemorrhage  has  not  been  violent,  it  spreads  out  under  the  arach- 


24 


APPLIED   ANATOMY. 


noid  in  the  subarachnoid  space.  If,  however,  the  blood  has  escaped  with  consider- 
able force,  it  tears  its  way  through  the  arachnoid  and  spreads  in  the  subdural,  as  well 
as  through  the  subarachnoid  space.  The  origin  of  this  form  of  hemorrhage  is  the 
vessels  of  the  pia  mater.  The  arachnoid  does  not  give  rise  to  hemorrhages,  neither 
does  the  inner  surface  of  the  dura,  unless  it  has  previously  been  the  seat  of  pachy- 
meningitis interna. 

The  hemorrhage  is  the  result  either  of  injury  or  disease.  In  children  it  is 
usually  due  to  injury;  in  adults  to  either  injury  or  disease.  These  hemorrhages  are 
most  common  in  infancy  and  occur  in  childbirth.  They  are  due  apparently  to 
hard,  protracted  labor  or  injury  done  to  the  child  in  effecting  delivery  by  forceps, 
etc. ,  especially  in  infants  born  before  full  term.  They  are  a  cause  of  idiocy  and  the 
cerebral   palsies   of   childhood.      These   hemorrhages  in   the  new-born   have  been 


Olfactory  tract 
Optic  nerve 
Optic  chiasm 
Optic  tract 

3rd — motor 

oculi 


4th — trochlear 
(pathetic) 

5th — trigemi- 
.^     "  iial  (trifacial) 


6th — abducent 

7th — facial 
8th — auditory 

9th — glosso- 
phar\iigeal 
10th — vagus 
(pueumogas- 
tric) 

nth — spinal 
accessory 


1 2th — h  ypoglossal 


Fig.  28. — Base  of  brain,  showing  exit  of  cranial  nerves. 


recognized  by  the  convulsions  they  produce,  and  successful  operations  have  been 
performed  for  their  relief  (see  Harvey  Gushing — "Surgical  Intervention  for  the 
Intracranial  Hemorrhages  of  the  New-born" — Am.  Jour.  Med.  Set.,  October,  1905). 
Injuries  received  later  in  life  from  blows  on  the  head  often  produce  subdural  or  pial 
hemorrhages,  without  breaking  the  overlying  bone.  They  are  found  either  at  the  site 
of  impact  or  on  the  side  opposite  that  on  which  the  blow  was  received,  the  latter  being 
produced  by  contre-coup.  When  pial  hemorrhage  occurs  from  disease,  it  is  usually 
from  rupture  of  an  aneurism  of  one  of  the  vessels  of  the  pia  mater.  If  it  does  not  break 
through  the  arachnoid  into  the  subdural  space,  it  may  spread  over  a  considerable 
portion  of  the  cerebral  cortex,  especially  filling  the  sulci.  Unless  the  quantity  is  quite 
large,  so  that  it  interferes  with  the  motor  area,  hemiplegia  will  not  occur.  Convulsions 
may  occasionally  occur  from  irritation  of  the  cortex.  Blood  in  the  subdural  space 
may  travel  along  the  base  of  the  brain  and  into  the  sheath  of  the  optic  nerve. 


THE    BRAIN. 


25 


THE  BRAIN. 

The  affections  of  the  brain  of  most  anatomical  interest  are  those  mvolving  its 
circulation,  the  motor  areas,  and  the  motor  paths.  Paralyses  may  arise  from  (a) 
interference  with  the  motor  areas  in  the  cortex  by  hemorrhages,  injuries,  or  tumors; 
{b)  destruction  of  the  motor  paths  from  the  cortex  to  their  point  of  exit  from  the 
brain;  (c)  injury  of  the  nerves  at  their  exit  from  the  brain. 

Disturbances  of  the  circulation  may  be  either  of  the  nature  of  anaemia  or  ischse- 
mia,  causing  softening,  or  of  congestion,  causing  apoplexy. 

Tumors  of  the  brain  interfere  with  the  functions  of  the  part  in  which  they  are 
located,  as  do  also  wounds.  In  all  of  these  a  knowledge  of  brain  localization  is 
essential. 

THE  CIRCULATION  OF  THE  BRAIN. 

The  blood  reaches  the  brain  by  means  of  the  two  internal  carotid  and  the  two 
vertebral  arteries.     The  vertebrals  enter  through  the  foramen  magnum  and  unite  to 


/ 


A.  conimuiiicans  antericr 


A.  cerebri  anterior 


A.  carotis  interna 

A   rerebri  media 

A.  conimunicans  posterior 

A.  anterolateral 

A.  choroidea 

A.  cerebri  posterior 


A.  basilaris 


A  vertebralis 


Fig.  29. — Circulus  arteriosus  or  circle  of  Willis. 

form  the  basilar,  which  at  the  upper  border  of  the  pons  divides  into  the  two  pos- 
terior cerebrals.  These  give  off  two  small  branches  which  go  to  the  internal  carotids; 
they  are  the  posterior  communicating  arteries.  The  carotids  divide  into  the  anterior 
and  middle  cerebral  arteries,  the  anterior  communicating  with  one  another  by  means 
of  the  anterior  communicating  artery.  Thus  we  have  the  circle  of  Willis  {circulus 
arteriosus^,  formed  hy  Xk^o.  posterior  cerebral,  posterior  communicating,  internal  car- 
otid, anterior  cerebral,  and  anterior  comniunicating  arteries  on  each  side. 

The  blood  supply  of  the  brain  is  divided  into  an  anterior  division,  furnished  by 
the  carotids,  and  a  posterior  division,  supplied  through  the  basilar  and  posterior 
cerebrals.  The  communication  branch  running  between  these  two  sets  of  vessels  is 
so  ?mall  that  if  either  is  occluded  the  supply  of  blood  is  practically  cut  off  from  that 
point  and  ischaemia  results,  at  least  in  most  cases. 

The  anterior  division  is  subdivided  into  a  right  and  a  left  half  by  the  two  carotid 


26 


APPLIED   ANATOMY. 


arteries.  These  communicate  across  the  median  Hne  through  the  anterior  cerebral 
and  anterior  communicating.  Here  again  the  anterior  communicating  branch  is  so 
small  that  it  is  sometimes  unable  to  furnish  blood  to  the  opposite  side  of  the  brain 


Optic  nerve 

Ophthalmic  artery 
Third  nerve 

Fourth  nerve 

Pphthalmic  branch — 5th  nerve 
.Sixth  nerve 
Internal  carotid  artery 

Maxillary  branch— 5th  nerve 

Mandibular  branch — 5th 
nerve 

Gasserian  ganglion 
turned  forward 

Internal  jugular 
vein 


Fig.  30. — The  internal  carotid  artery  in  its  course  through  the  skull,  showing  its  relations  to  the  jugular  vein  and 
cranial  nerves.    The  Gasserian  ganglion  has  been  raised  from  its  bed  and  turned  forward. 

when  the  carotid  supply  of  one  side  is  shut  off.      This  may  cause  syncope,  stupor 
or   delirium,   hemiplegia,  and   often  softening   and  death.      These  results  have  not 


A.  cerebri  anterior 


A.  cerebri  media 


A.  cerebri  posterior 
Fig.  31. — Distribution  of  the  A.  cerebri  anterior  and  A.  cerebri  posterior  on  the  medial  surface  of  the  brain. 

infrequently  followed  ligation  of  the  carotid  artery  in  cases  of  aneurism.  Obstruc- 
tion of  one  vertebral  artery  would  produce  no  effect  because  circulation  would 
be  restored  by  the  other  vertebral  through  the  basilar. 


THE   BRAIN. 


27 


Internal  Carotid  Artery. —  The  internal  carotid  artery  (Fig.  30)  enters  the 
petrous  portion  of  the  temporal  bone,  then  turns  inward  and  upward  through  the  for- 
amen lacerum  medium,  then  forward  through  the  caxernous  sinus  and  finally  turning 

A.  cerebri  anterior 


issura  parieto-occipitalis 


A.  cerebri  pos- 
terior 


A.  cerebri  media 


Fig.  32. — Distribution  of  the  A.  cerebri  anterior,  A.  cerebri  posterior,  and  A.  cerebri  media  on  the  lateral 

surface  of  the  brain. 

upward  gives  off  the  ophthalmic  artery;  it  then  pierces  the  dura  mater  just  behind 
the  anterior  clinoid  process,  where,  after  giving  ofi  the  posterior  communicating 
and  anterior  choroid,  it  divides  into  the  anterior  and  middle  cerebral  arteries.      ■• 


A.  communicans  anterior 

A.  cerebri  anterior 

A.  carotis  interna 

A.  cerebri  media 

A.  choroid  anterior 

A.  communicans  posterior 


A.  cerebri  posterior 


Temporal  lobe 


enticulostriate 


Fig.  33. — Arteries  of  the  base  of  the  brain,  especially  the  branches  of  the  middle  cerebral  giving  rise  to  apoplexy. 


Anterior  Cerebral  Artery. — The  anterior  cerebral  (Fig.  31)  passes  forward  and 
inward  over  the  anterior  perforated  space,  between  the  olfactory  and  optic  nerves,  to 
the  median  fissure.  It  gives  of?  the  anterior  communicating  artery  at  this  point,  which 
joins  the  anterior  cerebral  of  the  opposite  side.     The  main  trunk  then  runs  upward 


28 


APPLIED   ANATOMY. 


In  the  longitudinal  fissure  on  the  corpus  callosum,  giving  branches  to  the  frontal  and 
parietal  lobes,  and  finally  anastomoses  at  the  posterior  end  of  the  corpus  callosum 
with  the  posterior  cerebral.  This  shows  the  wide  extent  of  brain  tissue  on  the  medial 
surface  of  the  brain  which  would  be  affected  by  the  blocking  of  this  vessel  by  an 
embolus. 

The  terminal  branches  of  the  anterior  cerebral  spread  laterally  over  the  surface 
of  the  brain  (Fig.  32)  outward  from  the  longitudinal  fissure  for  a  short  distance, 
about  2  cm.  As  it  crosses  the  anterior  perforated  space,  it  gives  oH  the  antero- 
median perforating  (ganglionic)  arteries  which  pierce  the  lamina  cinerea  to  supply 
the  anterior  portion  of  the  caudate  nucleus  above. 

Middle  Cerebral  Artery, —  The  middle  cerebral  artery  passes  upward  and 
outward  in  the  fissure  of  Sylvius,  dividing,  when  opposite  the  island  of  Reil,  into  the 
branches  which  supply  the  cortex  of  the  brain  (see  Fig.    32).      On  its  way  toward 


Degenerative  area 

Corpus  callosum 

Nucleus  caudatus 
Apoplectic  area 
Internal  capsu'.e 

Nucleus  lentiformis 


Crura  cerebri 


i    Medulla  oblongata 

V^— — Decussation 


Fig.  34. — Showing  the  degenerative  and  apoplectic  areas  of  the  brain  and  the  course  pursued  by  the  motor 
fibres  from  the  cortex,  through  the  niternal  capsule,  crura,  pons,  and  medulla  to  the  decussation,  where  they 
cross  the  median  line  to  supply  the  opposite  side  of  the  body. 

the  island  of  Reil,  at  the  commencement  of  the  fissure  of  Sylvius,  many  small  straight 
branches  enter  the  brain  substance  to  supply  the  basal  ganglia.  Two  or  three  supply 
the  caudate  nucleus,  others,  called  the  anterolateral  perforating  (ganglionic),  enter 
the  anterior  perforated  space  to  supply  the  lenticulostriate  ganglion  and  the  anterior 
portion  of  the  thalamus.  One  of  the  largest  of  these  arteries,  the  lenticulostriate,  has 
been  called  the  artery  of  cerebral  hemorrhage,  by  Charcot,  on  account  of  the  frequency 
with  which  it  is  found  ruptured  in  cases  of  apoplexy  (Fig.  33). 

Anterior  Choroid. — The  anterior  choroid  artery  comes  sometimes  from  the 
internal  carotid  and  sometimes  from  the  middle  cerebral.  It  passes  backward  and 
outward  on  the  optic  tract  and  crus  cerebri  and  enters  the  transverse  fissure  at  the 
descending  horn  of  the  lateral  ventricle.    It  ends  in  the  choroid  plexus  (see  Fig.  33). 

Posterior  Cerebral  Artery. — The  posterior  cerebral  artery  passes  outward  over 
the  crus  cerebri,  just  above  the  pons,  to  the  under  surface  of  the  posterior  portion  of 
the  cerebral  hemisphere.  Before  it  receives  the  posterior  communicating  artery  it  gives 
off  the  posteromedian  perforating  (ganglionic)  arteries,  which  enter  the  posterior 
perforated  space  to  supply  the  thalamus  and  third  ventricle.     Just  beyond  the  poste- 


THE   BRAIN. 


29 


nor  communicating  artery  it  gives  off  the  posterolateral  perforating  (ganglionic; 
arteries,  which  supply  the  posterior  portion  of  the  optic  thalamus,  crus  cerebri,  and 


Velum  interpositum 
Middle  commissure    / 
Ciioroid  plexus 
Foramen  of  Monro 
Septum  lucidum 


Posterior  commissure 

Pineal  body 

Splenium 


Corpora  quadri- 
gemina 


Anterior  commissure 
Optic  nerve 

Optic  chiasm 

Pituitary  body 


Mammillary  body 

Aqueduct  of  Sylvius 


4th  ventricle 
Fig.  35.  -Medial  section  of  the  brain. 


corpora  quadrigemina.  The  branches  to  the  cortex  supply  a  small  portion  of  the 
inferior  surface  of  the  temporosphenoidal  lobe  and  the  occipital  lobe  as  seen  in 
Figs.  31  and  32. 


Corpus  callosum 

Septum  lucidum 
Caudate  nucleus 


Choroid  plexus 
Velum  interpositum 
Veins  of  Galen 


Fig.  36. — Horizontal  section  of  brain ;  the  corpus  callosum  and  fornix  have  been  removed,  exposing  the  lateral 
ventricles,  with  the  caudate  nuclei  projecting  into  them  anteriorly  and  the  velum  interpositum  farther  back,  with 
the  choroid  plexus  at  the  sides  and  the  veins  of  Galen  nearer  tfie  middle  line.  The  lateral  ventricles  in  this  brain 
are  somewhat  larger  than  usual. 


30 


APPLIED   ANATOMY. 


Cerebral  Softening. — This  occurs  in  the  young  from  embohsm ;  it  then  affects 
the  cortex,  but  the  more  common  variety  is  caused  by  thrombosis  in  arteries  which 
are  diseased,  usually  in  the  aged.  The  part  farthest  from  the  source  of  blood 
supply  is  the  most  apt  to  suffer,  therefore  we  find  it  occurring  most  frequently  in 
the  anterior  capsuloganglionic  region,  just  above  the  usual  site  of  apoplexy  (Fig.  34). 
The  affected  area  will  be  seen  to  be  most  remote  from  both  the  cortical  and  basal  blood 
supply.  The  perforating  arteries  supplying  this  region  are  in  the  nature  of  terminal 
branches  and  do  not  anastomose  to  any  extent  either  with  each  other  or  with  the 
branches  coming  from  the  cortex,  hence  their  occlusion  inflicts  irreparable  damage. 

Apoplexy. —  By  apoplexy  is  meant  the  rupture  of  a  blood-vessel  with  conse- 
quent extravasation  of  blood,  either  in  or  on  the  brain.  It  may  occur  in  any  portion 
of  the  brain,  and  either  from  the  arteries  of  the  base^  or  from  the  smaller  arteries  of 


Lateral  ventricle 


Caudate  nucleus 

Internal  capsule, 
anterior  limb 

Lenticular  nucleus  - 

Claustrum 

Internal  rapsiile, 
posterior  limb 

Thalamus 

Corpora  quadrigemina 

Lateral  ventricle, 
inferior  horn 


Septum  lucidum 

Fornix — anterior  pillar 


Fig.  37. — Horizontal  section  of  the  brain,  showing  the  internal  capsule  and  its  relation  to  the  lateral  ventricles. 


the  cortex.  The  former  is  the  more  frequent.  The  arteries  that  most  often  rupture 
are  the  branches  of  the  middle  cerebral  which  enter  the  anterior  perforated  space, 
especially  its  outer  portion.  One  of  the  largest  of  these  anterolateral  arteries,  as  has 
already  been  mentioned,  known  as  the  lenticulostriate,  has  been  called  by  Chaicot 
the  artery  of  cerebral  hemorrhage. 

The  portions  of  the  brain  usually  affected  are  the  posterior  portion  of  the  len- 
ticular nucleus,  internal  capsule,  and  surrounding  parts. 

Figure  35  is  a  medial  section  of  the  brain,  giving  a  lateral  view  of  the  ventricles. 

Figure  36  is  a  horizontal  transverse  section  of  the  brain,  opening  up  the  ventri- 
cles. In  front  are  seen  the  two  lateral  ve7itricles,  separated  by  the  septtivi  hicidum. 
The  cavity  shown  in  the  septum  lucidum  is  the  so-called  y?/?/^  ventricle.  The  round 
body  bulging  into  the  lateral  ventricle  and  forming  its  floor  is  the  caudate  nucleus 
portion  of  the  corpus  striatum.  The  third  ventricle  is  posterior  and  below  the  lateral 
ventricles,  and  extends  from  the  septum  lucidum  in  front  to  the  posterior  pillars  of 
the  fornix  behind.  It  extends  from  side  to  side  as  one  large  cavity  with  no  median 
partition.  Bulging  into  the  third  ventricle  on  each  side  are  the  {optic)  thalami. 
They  are  separated  from  the  corpora  striata  by  some  white  fibres,  the  tccnia  semicircu- 
laris.     To  the  inner  side  of  the  taenia  semicircularis  is  seen  the  choroid  plexus,  which 


THE   BRAIN. 


31 


runs  down  anteriorly  over  the  thalamus  to  the  foramen  of  Monro,  through  which 
it  enters  the  lateral  ventricle.  Two  large  veins,  the  veiris  of  Galen,  pass  down 
near  the  middle  line  of  the  third  ventricle  to  empty  into  the  straight  sinus.  Pos- 
teriorly, the  choroid  plexus  follows  the.  descending  horn  of  the  lateral  ventricles. 
The  choroid  plexus  hangs  from  the  under  surface  of  the  velum  interpositum,  which 
is  a  fold  of  the  pia  mater  entering  through  the  transverse  fissure.  The  veins  of  Galen 
run  between  the  two  layers  of  the  velum  interpositum. 

Turning  now  to  Fig.  37,  showing  a  somewhat  deeper  transverse  horizontal 
section,  running  through  the  corpus  striatum  and  thalamus,  it  will  be  seen  that  to 
the  outer  side  of  the  corpus  striatum  and  thalamus  is  a  white  layer  constitut- 
ing the  internal  capsule.  It  divides  the  corpus  striatum  into  two  parts,  one  to  its 
inner  side,  which  projects  into  the  lateral  ventricle,  called  the  caudate  nucleus,  and 


Degenerative  area 

Corpus  callosum 

Nucleus  caudatus 
Apoplectic  area 
Internal  capsule 

Nucleus  lentiformis 


Crura  cerebri 


Medulla  cblong^ata 
Decussation 


38-— Showmw  the  degenerative  and  apoplectic  areas  of  the  brain  and  the  course  pursued  by  the  motor 
fibres  from  the  cortex,  throuj^^h  the  niternal  capsule,  crura,  pons,  and  medulla  to  the  decussation,  where  they 
cross  the  median  line  to  supply  the  opposite  side  of  the  body. 

the  other  to  its  outer  side,  called  the  lenticular  nucleus.  To  the  inner  side  of  the 
posterior  portion  of  the  lenticular  nucleus  and  internal  capsule  is  seen  the  thal- 
amus. To  the  outer  side  of  the  lenticular  nucleus  one  sees  other  white  fibres  called 
the  external  capsule.  An  apoplectic  hemorrhage  occurring  in  the  lenticular  nucleus 
or  internal  capsule  may  push  forward  and  rupture  into  the  lateral  ventricle.  It  may 
go  backward  and  involve  the  anterior  portion  of  the  thalamus  and  burst  into 
the  third  ventricle,  and  if  it  extends  outward  it  involves  the  external  capsule.  Some- 
times, if  the  hemorrhage  is  low  down,  it  ruptures  downward  through  the  base  of  the 
brain,  showing  itself,  of  course,  at  the  anterior  perforated  space.  Fig.  33  shows  these 
structures  as  seen  in  a  medial  section  of  the  brain. 

In  Fig.  38  there  is  a  coronal  transverse  section  of  the  brain,  showing  the  course 
of  fibres  of  the  internal  capsule  from  the  cortex  of  the  brain  through  the  corpus 
striatum,  between  the  lenticular  and  caudate  nuclei :  then,  forming  the  cr7is  cerebri, 
the  fibres  pass  through  the  pons  and  medulla  to  enter  the  spine,  decussate,  and 
pass  to  the  extremities.  This  constitutes  the  motor  pathway  from  the  cortex  to  the 
extremities,  and  when  it  is  injured  in  apoplexy,  the  extremities  of  the  opposite  side 
are  paralyzed. 


32 


APPLIED    ANATOMY. 


Clot  in  pons,  upper 
f — portion 

'i 

Clot  in  lower 
portion 

Facial  nerve 


Hemorrhage  into  the  Pons — Crossed  Paralysis, — Apoplexy  may  also  occur 
in  other  portions  of  the  brain.     It  may  occur  in  the  pons  (see  Fig.  39).     This  produces 

two  different  sets  of  symptoms,  accord- 
W^  1 1  ing  to  its    location,    which  is    due  to 

the  fact  that  the  fibres  of  the  seventh 
or  facial  nerve,  in  their  passage  from 
the  cortex  to  the  face,  decussate  in  the 
pons.  If  a  small  hemorrhage  occurs 
into  the  upper  portion  of  the  pons,  it 
will  destroy  the  motor  fibres  to  the 
face  and  the  extremities  of  the  oppo- 
site side.  If,  however,  the  hemor- 
rhage is  below  the  point  of  decussa- 
tion, the  side  of  the  face  on  the  side  of 
the  lesion  will  be  paralyzed  and  the 
extremities  of  the  opposite  side,  thus 
producing  what  is  known  as  crossed 
paralysis,  that  is,  a  paralysis  of  the  face 
on  one  side  and  of  the  extremities  on 
the  other. 

Cortical  Apoplexy. —  Hemor- 
rhages of  the  cortex  are  apt  to  be  less 
in  extent  and  more  localized  on  ac- 
count of  the  smaller  size  of  the  ves- 
sels affected.  They  either  destroy  or 
irritate  the  bram  at  the  site  of  injury,  and  produce,  if  they  involve  certain  areas 
of  the  brain,  definite  peripheral  symptoms  which  serve  to  indicate  the  seat  of  lesion. 


Spinal  nerves 


Fig.  39. — Diagram  illustrative  of  crossed  paralysis.  A 
clot  in  the  upper  portion  of  the  pons  causes  paralysis  of  the 
muscles  of  the  face  and  extremities  of  the  same  side  of  the 
body.  A  clot  in  the  lower  portion  of  the  pons  causes  paraly- 
sis of  one  side  of  the  face  and  the  extremities  of  the  opposite 
side  of  the  body. 


THE  CEREBRAL  LOBES. 

Each  cerebral  hemisphere  is  composed  of  five  lobes,  called  the/ro?ifa/,  parietal, 
occipital,  temporosphenoidal,  and  central,  or  isla^id  of  Reil. 

The  frontal  lobe  comprises  the  anterior  portion  of  the  brain,  as  far  back  as  the 
fissure  of  Rolando  or  central  sulcus,  and  as  far  toward  the  base  as  the  fissure  of  Sylvius. 


us  parietalis 


lobus  frontalis 


Lobus  occipitalis 


Lobus  centralis  or  insula 


Lobus  temporalis 


Fig.  40. — Lobes  of  the  brain. 

The  parietal  lobe  extends  from  the  fissure  of  Rolando  (central  sulcus)  in  front 
to  the  parieto-occipital  fissure  behind.  Below,  it  is  limited  anteriorly  by  the  fissure 
of  Sylvius,  while  its  posterior  portion  merges  into  the  temporosphenoidal  lobe. 

The  occipital  lobe  extends  posteriorly  from  a  line  joining  the  occipitoparietal 
fissure  above  to  the  pre-occipital  notch  below. 

The  temporosphenoidal  lobe  consists  of  that  portion  of  the  brain  below  the 
fissure  of  Sylvius,  as  far  back  as  the  pre-occipital  notch.  It  occupies  the  middle 
fossa  of  the  skull. 


THE   BRAIN. 


33 


The  central  lobe  or  island  of  Reil,  also  called  the  insula,  consists  of  five 
to  seven  convolutions  which  radiate  upward;  it  can  be  seen  by  separating  the  two 
sides  of  the  anterior  portion  of  the  fissure  of  Sylvius. 

THE   FISSURES   AND   CONVOLUTIONS   OF  THE   BRAIN. 

The  surface  of  the  brain  is  wrinkled  or  thrown  into  folds,  producing  elevations 
and  depressions.  The  elevations  are  called  convolutions  or  gyri,  and  the  depres- 
sions, fissures  or  sulci. 

The  fissures  are  called  main  or  subsidiary  fissures,  according  to  their  impor- 
tance. The  five  main  fissures  are  the  longitudinal  fissure,  which  separates  the 
hemispheres;  the  transverse  fissure,  which  separates  the  cerebrum  and  cerebellum 
and  communicates  with  the  third  ventricle;  the  fissure  of  Sylviiis ;  the  fissure  of 
Rolando,  or  central  fissure,  and  the  parieto-occipital fissure. 


THE  LATERAL  SURFACE  OF  THE  HEMISPHERES. 

The  frontal  lobe  has  a  superior,  an  inferior,  and  a  precentral  sulcus.     The  first 
two  divide  the  anterior  portion  into  the  stiperior,  viiddle,  and  inferior  frontal  convo- 


Sulcus  praecentralis 

\ 
\ 


Sulcus  centralis  (Rolandi) 
Sulcus  post  centralis 

^Sulcus  interparietalis 


Sulcus  frontalis 
superior 


Sulcus  frontalis 
inferior 


Fissura  parieto- 
occipitalis 


Sulcus  occipitalis 
transversus 


Sulcus  occipitalis 
lateralis 


Fissura  lateralis  (Sylvii 

Sulcus  temporalis  superior 

Sulcus  temporalis  medius 

Fig.  41. — Fissures,  sulci,  and  gyri  (convolutions)  of  the  lateral  surface  of  the  cerebral  hemisphere. 

lutions.  That  portion  of  the  inferior  or  third  left  frontal  convolution  which  surrounds 
the  ascending  limb  of  the  fissure  of  Sylvius  is  called  Brocd' s  convolution,  and  is 
the  centre  for  speech.  Posterior  to  these  and  running  upward  and  backward,  form- 
ing the  anterior  wall  of  the  central  fissure,  is  the  precentral  or  ascendiiig  frontal 
convolution. 

The  convolution  forming  the  anterior  extremity  of  the  parietal  lobe  and  the 
posterior  wall  of  the  central  sulcus  or  fissure  of  Rolando  is  called  the  postcentral  or 
ascendiiig  parietal  convolutio7i.  Immediately  behind  it  is  the  postcentral  or  inter- 
parietal sulcus.  The  upper  portion  of  this  sulcus  divides,  one  branch  going  up- 
ward and  one  backward.  Immediately  above  the  posterior  branch  is  the  superior 
parietal  gyrus  or  lobule,  and  below  it  and  surrounding  the  posterior  extremity  of  the 
fissure  of  Sylvius  is  the  supramarginal  gyriis.  Posterior  to  the  supramarginal  gyrus 
and  surrounding  the  posterior  extremity  of  the  superior  temporal,  or  temporosphe- 
noidal  sulcus  is  the  convolution  known  as  the  a^igular  gyriis. 

The  occipital  lobe  on  its  convex  surface  is  divided  into  superior  and  inferior 
occipital  convolutions  by  the  lateral  occipital  sulcus. 

The  temporal  or  temporosphenoidal  lobe  is  also  divided  into  superior,  middle, 
and  inferior,  or  first,  second,  and  third  temporal  convolutions  hy  the  superior,  or  par- 
allel, and  middle  fissures.  On  the  under  surface  is  a  fourth  temporal  convoltition, 
separated  from  the  third  by  the  inferior  temporal  fissure.  These  fissures  may  not  be 
distinct. 


34 


APPLIED   ANATOMY. 


THE  MEDIAL  SURFACE  OF   THE   HEMISPHERES. 

If  now  the  medial  surface  of  the  hemisphere,  which  forms  one  side  of  the  longi- 
tudinal fissure,  be  examined,  there  is  seen  a  large  convolution  running  just  above  and 
parallel  with  the  corpus  callosum.  It  is  called  the  gyrus  cinguli  (^fornicatiis).  Below 
and  separating  it  from  the  corpus  callosum  is  the  callosal  fissure;  above  it  is  the  calloso- 
marginal  fissure.  The  convolution  above  the  latter,  forming  the  margin  of  the  hem- 
isphere, is  the  viarginal  convohdion.  The  callosomarginal  fissure  at  its  posterior 
portion  turns  upward  and  ends  on  the  margin  of  the  hemisphere,  just  posterior  to  the 
fissure  of  Rolando,  or  central  fissure,  and  serves  to  identify  it.  This  marks  the  pos- 
terior limit  of  the  frontal  lobe.  The  posterior  end  of  the  frontal  lobe  surrounds  the 
upper  end  of  the  central  fissure  and  on  that  account  is  called  the  paracentral  lobule. 
Its  anterior  boundary  is  marked  by  the  paracentral  fissure,  or  sulcus.  Between  the 
callosomarginal  fissure  in  front  and  the  parieto-occipital  fissure  behind  is  the  parietal 
lobe,  called,  from  its  square  shape  on  the  medial  surface,  the  quadrate  lobule,  or  from 
being  anterior  to  the  cuneus  lobule,  the  prectineus.      Running  downward  and  back- 


Fissura  centralis 
(Rolandi) 


Sulcus  cinguli  (callosomarginalis) 


Fissura  parieto- 
occipitalis 


Fissura  calcarina 
posterior 


Fissura  calcarina 
anterior 


Fissura  collateralis 

Sulcus  temporalis  inferior 

Fig.  42.— Gyri,  sulci,  and  fissures  of  the  medial  surface  of  the  cerebral  hemisphere. 

ward  from  the  deeper  portion  of  the  parieto-occipital  fissure  is  a  very  distinct  depres- 
sion called  the  calcarine  fissure.  These  two  fissures  include  a  wedge-shaped  piece 
of  the  occipital  lobe  called,  from  its  shape,  the  cuneus  lobule.  It  is  of  interest  in 
reference  to  the  sense  of  sight. 


FUNCTIONS  OF  THE  CORTEX  OF  THE  BRAIN: 

LOCALIZATION. 


CEREBRAL 


A  knowledge  of  the  functions  of  the  various  portions  of  the  brain  is  necessary 
in  order  to  localize  a  diseased  area.  The  diseases  and  injuries  to  which  the  brain 
is  exposed  oftentimes  do  not  involve  the  whole  brain,  but  only  certain  distinct  and 
isolated  parts.  The  brain  is  not  a  single,  homogeneous  organ  that  acts  only  as  a 
whole;  it  is  complex.  It  is  composed  of  a  number  of  separate  parts  or  areas,  which 
may  act  either  singly  or  in  conjunction  with  other  areas.  These  separate  areas  have 
different  functions,  so  that  if  the  disease  or  injury  is  limited  to  one  of  them,  we  have 
its  functions  abolished,  and  the  symptoms  produced  indicate  the  area  affected. 

These  areas  are  situated  on  the  surface  or  cortex  of  the  brain  in  the  gray  matter. 
They  receive  impressions  from,  and  transmit  impulses  to,  all  parts  of  the  body 
through  the  white  matter  or  fibres  of  the  brain.  An  injur}'  to  the  cortex  or  gray 
matter  destroys  the  originating  and  receptive  centres.  An  injury  to  the  white  matter 
destroys  the  paths  to  and  from  these  centres  and  therefore  prevents  them  from 
receiving  impressions  or  sending  out  impulses.  Thus,  we  may  have  a  paralysis  of 
the  leg  and  arm  caused  by  an  injury  to  the  leg  and  arm  centres  in  the  cortex  of 
the  brain,  as  by  a  hemorrhage  from  a  fracture,  or  we  can  have  the  same  paralysis 


THE   BRAIN. 


35 


produced  by  an  injury  to  the  path  leading  from  those  centres,  the  motor  tract  as  it 
is  called,  by  a  hemorrhage,  as  from  apoplexy,  involving  the  corresponding  white 
matter  fibres. 

The  exact  localization  of  the  functions  of  all  parts  of  the  brain  has  not  been 
accomplished,  but  the  functions  of  many  areas  have  been  definitely  proven.  In 
cases  of  brain  tumor,  abscess,  hemorrhage,  injury,  etc. ,  a  knowledge  of  these  areas 
enables  one  to  localize  the  seat  of  the  lesion. 


FUNCTIONS  OF  THE  CONVOLUTIONS  ON  THE  SURFACE  OF  THE  CEREBRUM. 

The  frontal  lobe  may  be  conveniently  divided  into  three  areas;  prefrontal,  mid- 
frontal,  and  postfrontal.  The  prefrontal  area  embraces  all  the  superior,  middle, 
and  inferior  frontal  convolutions,  with  the  exception  of  their  posterior  ends.  On 
the  medial  side  it  reaches  to  the  callosomarginal  fissure.  The  function  of  the  pre- 
frontal area  is  said  to  be  that  of  higher  cerebration,  as  attention,  judgment,  and  com- 
parison. This  region,  particularly  the  lower  portion,  is  liable  to  injury,  owing  to  its 
anterior  position  and  to  the  fact  that  it  overlies  the  orbit.  The  roof  of  the  orbit  is 
quite  thin  and  liable  to  fracture  by  penetrating  bodies,  as  umbrellas,  canes,  etc. 
Sometimes  a  portion  of  this  part  of  the  brain  may  be  destroyed  without  marked 
interference  with  the  mental  qualities  of  the  patient.     This  occurred  in  the  case  of  a 


Fig.  43.— Diagram  illustrating  the  probable  functions  of  the  lateral  surface  of  the  brain. 

boy  who  was  struck  in  the  eye  by  a  carriage  pole  (personal  observation).  The  eye 
was  burst,  necessitating  its  removal.  Several  pieces  of  the  fractured  bone  of  the 
roof  of  the  orbit  w-ere  removed  and  brain  tissue  came  away  for  several  days.  The 
boy  recovered  and  for  sixteen  years  apparently  had  no  resulting  mental  deficiency. 

The  midfrontal  area  embraces  the  posterior  portion  of  the  superior  and 
middle  convolutions,  with  the  upper  posterior  portion  of  the  inferior.  It  is  con- 
cerned in  certain  movements  of  the  eyes  and  lids,  and  also  in  turning  the  head 
toward  the  opposite  side.  This  midfrontal  division  is  the  most  anterior  portion  of 
what  is  called  the  motor  area. 

Speech  Centre,  or  Broca's  Convolution. — The  centre  of  speech  is  located 
in  right-handed  people  in  the  posterior  portion  of  the  third  left  frontal  convolution, 
where  it  arches  around  the  ascending  limb  of  the  fissure  of  Sylvius.  It  is  called 
Broca's  convolution.  The  faculty  of  writing  or  written  speech  is  attributed  to  the 
graphic  centre  in  the  posterior  extremity  of  the  second  frontal  convolution  just  above 
and  behind  Broca's  convolution. 

The  postfrontal  area  embraces  the  ascending  frontal  convolution  in  front  of 
the  fissure  of  Rolando  or  central  fissure.  It  is  concerned  in  the  various  movements 
of  the  trunk  and  extremities,  and  forms  the  anterior  portion  of  the  Rolandic  area; 
it  will  be  considered  under  that  head. 

The  Rolandic  Area. — This  is  the  area  which  gives  rise  to  most  of  the  voluntary 
movements  of  the  body.      When  affected,  it  causes  positive  symptoms  of  paralysis 


36 


APPLIED   ANATOMY. 


or  contraction  of  the  muscles  connected  with  it,  and  is  the  region  most  frequently 
affected  by  injuries.  This  is  partly  due  to  the  fact  of  its  proximity  to  the  middle 
meningeal  artery,  as  a  hemorrhage  from  that  vessel  produces  a  clot  which  covers 
and  involves  this  area. 

The  Rolandic  area  embraces  the  ascending  frontal,  or  precentral,  and  posterior 
portion  of  the  three  frontal  convolutions,  the  former  being  in  front  of  the  fissure 


Fig.  44.— Diagram  illustrating  the  motor  areas  of  the  lateral  surface  of  the  brain. 

of  Rolando,  or  central  fissure.  The  fissure  of  Rolando  passes  downward  and  for- 
ward from  the  longitudinal  fissure,  at  an  angle  of  about  70°,  nearly  to  the  fissure  of 
Sylvius,  being  separated  from  it  by  the  joining  of  the  ascending  parietal  and  ascend- 


FiG.  45.— Diagram  illustrating  the  probable  functions  of  the  gyri  (convolutions)  of  the  medial  surface  of  the  brain. 

ing  frontal  convolutions.      Sherrington  and  Griinbaum  have  shown  that  the  motor 
area  is  almost  exclusively  anterior  to  the  central  fissure. 

The  upper  portion  of  the  motor  area,  near  the  longitudinal  fissure,  is  concerned 
with  the  movements  of  the  toes  and  lower  extremity.  The  leg  centres  are  toward 
the  upper  end  of  the  central  fissure;  next  are  those  of  the  abdomen  and  chest. 
The  arm  centres  are  toward  the  middle,  and  the  face  centres,  including  the  larynx. 


THE   BRAIN. 


37 


tongue,  and  platysma  myoid  muscle,  around  its  lower  extremity.  The  leg,  arm,  and 
face  centres  are,  respectively,  opposite  the  posterior  extremities  of  the  superior, 
middle,  and  inferior  frontal  convolutions. 

The  upper  portion  of  the  motor  area  passes  over  the  upper  margin  of  the  hemi- 
sphere and  down  on  its  medial  side  almost  as  far  as  the  callosomarginal  fissure  and 
paracentral  lobule. 

The  Sensory  Area. — The  portions  of  the  cerebrum  involved  in  cutaneous 
and  muscular  sensibility  embrace  the  posterior  portion  of  the  parietal  convolutions, 
the  precuneus  or  quadrate  lobule,  and  gyrus  fornicatus  as  far  forward  as  the  motor 
area  on  the  medial  aspect. 

The  visual  area  embraces  the  occipital  lobe,  particularly  its  cuneus  lobule, 
and  region  of  the  calcarine  fissure  on  the  medial  surface  of  the  hemisphere.  The 
anterior  portion  of  the  occipital  lobe  and  the  region  of  the  angular  gyrus  are  con- 


Foramen  interventriculare 

Conimissura  niedius 


Thalamus 


Ventriculum  lateralis 

Corpus  striatum 

Commissura  anterior 


Conimissura  posterior 
Corpus  pineale 


f      Corpora  quadrigemina 


Ventriculum  quartus 
Medulla 

Fig.  46.— Foreshortened  view  showing  corpus  striatum,  thalamus,  corpora  quadrigemina,  lateral,  third,  and 

fourth  ventricles,  etc. 

earned  in  the  more  complex  phenomena  of  sight,  and  their  destruction  produces 
word-blindness.  Destruction  of  the  centres  on  both  sides  produces  what  has  been 
called  mind-blindness,  because  objects  can  no  longer  be  recognized. 

The  Auditory  Area. — The  centre  for  hearing  is  located  in  the  superior  and 
middle  temporosphenoidal  convolutions.  It  requires  destruction  of  these  convo- 
lutions on  both  sides  of  the  brain  to  produce  total  cerebral  deafness.  The  memory 
or  recognition  of  spoken  words  (word  hearing)  is  apparently  performed  by  the  pos- 
terior ends  of  the  superior  and  middle  (ist  and  2d)  temporosphenoidal  convolutions. 

Gustatory  Area. — The  sense  of  taste  is  supposed  to  be  located  on  the  under 
and  inner  surfaces  of  the  temporosphenoidal  lobe  or  fourth  temporal  convolution. 

Olfactory  Area. — The  sense  of  smell  is  supposed  to  involve  the  anterior  portion 
of  the  gyrus  fornicatus  and  the  upper  medial  portion  of  the  temporosphenoidal  lobe. 

The  cerebral  areas  for  both  smell  and  taste  have  not  been  as  yet  accurately 
determined. 

FUNCTIONS  OF  THE  BASAL  GANGLIA. 

Corpus  Striatum  and  Thalamus. — The  exact  functions  of  the  corpus  stria- 
tum, embracing  the  caudate  and  lenticular  nuclei,  and  of  the  thalamus  are  not 
known.  They  are  most  often  affected  in  apoplexies ;  lesions  of  the  corpus  striatum  are 
accompanied  by  disturbances  of  motion,  and  those  of  the  thalamus  by  disturbances  of 
sensation. 


38 


APPLIED   ANATOMY. 


Corpora  Quadrigemina. — The  anterior  corpora  quadrigemina  are  associated 
with  sight,  the  posterior  possibly  with  hearing  and  equilibrium.  Note  their  prox- 
imity to  the  cerebellum. 


spinal  cord 


Fig.  47. — The  corona  radiata  or  projection  fibres  which  connect  the  cortex  above  with  the  thalamus,  corpus  striatum, 
tegmental  region,  pons,  medulla,  and  spinal  cord  below.     These  fibres  go  to  form  the  internal  capsule. 

Crura  Cerebri. — The  crura  cerebri  transmit  both  sensory  and  motor  impulses. 
Note  their  proximity  to  the  third  nerve,   as  they  are  apt  to  be  involved  by  the 


Cerebral  cortex 


same  lesions,  thus  accounting  for  paralyses 
or  sensory  disturbances  of  the  trunk  or  ex- 
tremities accompanied  by  ocular  paralysis. 
Pons  Varolii. — The  pons  transmits 
the  motor  or  pyramidal  tract,  and  also  the 
fifth,  sixth,  and  seventh  nerves.  Implication 
of  the  seventh  or  facial  nerve,  together  with 
the  motor  tract,  has  already  been  alluded  to 
(page  32).  If  the  sixth  or  abducent  nerve 
is  involved,  the  external  rectus  muscle  on 
that  side  will  be  paralyzed.  If  the  fifth,  or 
trifacial  nerve  is  affected,  irritation  of  its 
motor  root  may  produce  trismus  or  clench- 
ing of  the  jaws,  and  interference  with  its 
sensory  root  may  cause  anaesthesia  of  one 
side  of  the  face. 

THE  CORONA  RADIATA,   INTERNAL 
CAPSULE,  AND  MOTOR  TRACT. 

The  corona  radiata  is  the  bundle  of  white 
fibres  which  spreads  out  like  a  fan  and  con- 
nects the  cortex  of  the  brain  with  the  basal 
ganglia  and  spinal  cord.  Proceeding  down- 
ward from  the  cortex,  the  corona  radiata  be- 
comes smaller  and  passes,  in  the  form  of  a 
band,  between  the  lenticular  nucleus  on  the 
outside  and  the  caudate  nucleus  and  thal- 
amus on  the  inside.  This  band  is  known 
as  the  internal  cupsnle.  It  transmits  in  its 
anterior  portion  fibres  from  the  prefrontal  or 
higher  psychical  area;  then  come  the  motor 

paths ;  and  still  farther  back,  in  the  posterior  third  of  the  posterior  portion,  sensory  fibres. 
T^x^  functions  of  the  external  capside,  which  lies  to  the  outer  side  of  the  lenticular 

nucleus,  are  not  known. 


Pyramidal 

decussation 
Lateral 

pyramidal  tract 
Direct 

pyramidal  tract 


Spinal  nerve 


Fig.  48. — Diagram  showing  course  and  decussa- 
tion of  corticospinal  (pyramidal)  tract  ;  M,  medulla; 
P.poiis;  CP,  cerebral  peduncle;  T,  thalamus;  C,  L, 
caudate  and  lenticular  nuclei ;  CC,  corpus  callosum. 
(Piersol.) 


THE   BRAIN. 


39 


The  motor  fibres  of  the  ijitenial  capsule  pass  downward  through  the  anterior 
portion  of  the  crus  cerebri  and  pons  into  the  medulla,  at  the  lower  part  of  which 
the  majority  decussate  and  pass  into  the  anterior  columns  of  the  cord  as  the/jj'ra;«- 
idal  tracts.  Thus,  it  is  seen  that  destruction  of  any  portion  of  the  motor  tract, 
from  the  point  oi  pyramidal  decussation  below,  through  the  internal  capsule  to  the 
cortex  above,  will  cause  a  paralysis  on  the  opposite  side  of  the  body. 


CRANIOCEREBRAL  TOPOGRAPHY. 

For  the  purpose  of  operating  on  the  brain  it  is  essential  to  know  the  bony  land- 
marks of  the  skull,  the  lower  level  of  the  brain,  and  the  relation  which  the  various 
fissures  and  convolutions  bear  to  the  surface. 

The  most  important  fissures  are  the  longitudinal,  Sylvian,  Rola7idic,  3.nd parieto- 
occipital. If  these  can  be  properly  located,  the  convolutions  and  subsidiary  fissures 
can  be  readily  filled  in. 

BONY    LANDMARKS. 

Nasion. —  The  nasofrontal  suture  in  the  median  line. 

Glabella. — The  smooth  spot  in  the  median  line  on  the  frontal  bone  between 
the  superciliary  ridges.      It  is  about  on  a  level  with  the  upper  edge  of  the  orbit. 


Bregma 


Stephanion 


Sylvian  point 
Pterion 


Lambda 


Temporal  ridge 


Glabella 

External  angular  process 
—  Nasion 
Malar  tubercle 


Inion 


Asterion 


Fig.  49. — Landmarks  of  the  skull. 


Bregma. —  The  point  in  the  midline  where  the  sagittal  and  coronal  sutures 
cross.      It  corresponds  with  the  anterior  fontanelle  in  the  infant. 

Lambda. —  The  point  of  meeting  of  the  sagittal  and  lambdoid  sutures.  It  is 
about  6  cm.  (2  ^^  in. )  above  the  occipital  protuberance. 

Inion. —  The  external  occipital  protuberance. 

Pterion. —  This  name  was  given  by  P.  Broca  to  the  point  where  the  frontal, 
parietal,  and  sphenoid  bones  meet  in  the  region  of  the  temple.  It  is  about  2.5  cm. 
( I  in. )  behind  the  angular  process  and  should  not  be  confounded  with  the  Sylvian 
point,  which  is  1.5  cm.  (S/^  in.)  farther  posterior,  where  the  temporal,  parietal,  and 
sphenoid  bones  meet.  Horsley  called  this  latter  point  the  pterion.  The  region  of 
the  pterion  is  the  seat  of  the  anterolateral  fontanelle  in  the  foetus. 

Asterion. —  This  lies  2  cm.  (4  in.)  behind  the  base  of  the  mastoid  process, 
where  the  parietal,  occipital,  and  temporal  bones  meet.  It  is  on  the  superior  curved 
line  and  in  fetal  life  forms  the  posterolateral  fontanelle. 

Temporal  Ridge. — This  marks  the  upper  attachment  of  the  temporal  fascia 
and  muscle.      It  begins  at  the  external  angular  process  of  the  frontal  bone  and  ends 


40  APPLIED   ANATOMY. 

at  the  asterion.  Its  anterior  third  is  well  marked,  but  as  it  crosses  the  coronal  suture 
it  fades  away  and  gradually  broadens  out,  its  upper  margin  being  called  the  superior 
and  its  lower  the  inferior  temporal  ridge.  The  superior  ridge  marks  the  attachment 
of  the  superficial  layer  of  the  temporal  fascia,  the  inferior,  the  deep  layer. 

External  Angular  Process. —  This  is  the  outer  extremity  of  the  frontal  bone, 
where  it  articulates  with  the  malar.  The  line  of  the  suture  can  be  distinctly  felt  in 
the  living. 

Malar  Tubercle. —  This  is  the  small  bony  projection  on  the  posterior  edge  of 
the  malar  bone,  1.25  to  2  cm.  (3^  to  ^  in.)  below  the  frontomalar  suture. 

Stephanion. — The  point  where  the  temporal  ridge  crosses  the  coronal  suture. 

TOPOGRAPHICAL  POINTS. 

Pre-auricular  Point. —  The  depression  in  front  of  the  ear  and  just  behind  the 
condyle  of  the  lower  jaw. 

Sylvian  Point. —  Where  the  anterior  ascending  and  anterior  horizontal  limbs 
come  off  from  the  posterior  horizontal  limb  of  the  fissure  of  Sylvius.  It  lies  4  cm. 
(i^  in. )  posterior  and  a  little  above  the  external  angular  process,  at  the  junction  of 
the  parietal,  sphenoid,  and  temporal  bones. 

Superior  Rolandic  Point. —  Where  the  upper  end  of  the  line  marking  the 
Rolandic  fissure  crosses  the  median  line. 

Inferior  Rolandic  Point. —  Where  the  lower  end  of  the  line  marking  the 
Rolandic  fissure  crosses  the  line  of  the  Sylvian  fissure. 

The  Lower  Level  of  the  Brain. 

The  lower  level  of  the  brain  is  marked  by  a  line  beginning  in  the  median  line 
I  cm.  (f  in.)  above  the  nasion,  thence  above  the  orbit  i  cm.  from  its  edge  to  the 
external  angular  process;  from  here  it  goes  to  the  middle  of  the  zygoma,  thence 
backward  along  its  upper  border,  above  the  auditory  meatus  and  along  the  supe- 
rior curved  line  to  the  inion  (occipital  protuberance). 

FISSURES   AND  CONVOLUTIONS. 

The  conformation  of  the  various  fissures  and  convolutions  varies  so  much  within 
normal  limits  that  it  is  not  possible  to  outline  them  on  the  surface  of  the  scalp  or 
skull  with  absolute  exactness.  The  various  lines  which  are  laid  out  to  indicate  their 
course  are,  therefore,  only  approximate,  but  they  are  sufficiently  accurate  for  opera- 
tive purposes.  To  allow  for  variations,  the  openings  made  are  usually  large,  and  the 
motor  areas  are  sometimes  identified  by  the  application  of  an  electrode. 

Fissure  of  Sylvius  (fissura  cerebri  lateralis). — To  indicate  the  course  of 
the  Sylvian  fissure,  a  line  is  drawn  from  the  external  angular  process  of  the  frontal 
bone  through  a  point  2  cm.  (^  in.)  below  the  most  prominent  part  of  the  parietal 
eminence  and  ending  1.5  cm.  (^  in.)  above  the  lambda.  The  main  portion  of  the 
Sylvian  fissure  begins  2  cm.  (^  in.)  behind  the  angular  process;  2  cm.  farther  back 
or  42  mm.  ( i  f^  in. )  behind  the  angular  process  is  the  Sylvian  point,  where  the 
anterior  horizontal  and  anterior  ascending  limbs  are  given  ofi.  From  this  point  the 
posterior  horizontal  limb  passes  backward  to  2  cm.  (3/(  in.)  below  the  highest  point 
of  the  parietal  eminence  and  then  curves  upward  and  backward  for  a  distance  of 
1.25  cm.  to  2  cm.  (%  to  3^  in.). 

Central  Fissure,  or  Fissure  of  Rolando  (sulcus  centralis). — The  line  of 
the  central  fissure  begins  at  the  upper  Rolandic  point,  1.5  cm.  (^  in.)  behind  the 
middle  of  a  sagittal  line  passing  from  the  glabella  to  the  inion.  It  then  passes 
down  and  forward  at  an  angle  of  approximately  70°  (67^,  Chiene)  toward  the 
middle  of  the  zygoma  (Le  Fort)  to  end  at  the  lower  Rolandic  point,  where  it  inter- 
sects the  Sylvian  line.  It  is  about  9  cm.  (33^  in.)  long.  The  central  fissure  stops 
I  cm.  above  the  Sylvian  line  or  fissure. 

Parieto-occipital  Fissure  (fissura  parieto-occipitalis). — The  position  of 
this  fissure  is  quite  variable,  an  average  being  1.5  cm.  (^  in.)  above  the  lambda,  and 
extending  1.25  cm.  (^  in.)  out  from  the  median  line.  It  is  about  6  cm.  (2^^  in.) 
above  the  inion  and  on  or  below  the  line  of  the  Sylvian  fissure. 


THE   BRAIN. 


41 


Subsidiary   Fissures   and   Convolutions. 

The  precentral  and  postcentral  sulci  are  about  15  mm.  (|  in.)  anterior 
and  posterior  to  the  fissure  of  Rolando. 

The  inferior  frontal  convolution  lies  between  the  line  of  the  fissure  of 
Sylvius  below  and  a  line  just  below  the  temporal  ridge  above. 

The  middle  frontal  convolution  lies  under  the  frontal  eminence,  and  occu- 


Central  fissure  or 
fissure  of  Rolando 


Bregma 


Line  for  central  or 
Rolandic  fissure 

Precentral  sulcus 


Interparietal 
sulcus 


Postcentral 
sulcus 


Pai  ieto-occipital v-^ 

fissure 
Transverse  occip- 
ital sulcus 

Parietal  eminence 


Lateral  occipita 
sulcus 


Inion 


Transverse  or 
lateral  sinus' 


Posterior  horizontal  limb  of 
Sylvian  fissure 


Line  for  Sylvian  fissure 

Temporal  ridge 
Ascending  limb  of 
Sylvian  fissure 
Anterior  horizontal  limb 
Main  portion  of 
Sylvian  fissure 


Fig.  50. — Semidiagrammatic  view  of  head,  showing  relation  of  Rolandic  and  Sylvian  fissures  and  lines. 


pies  about  the  lower  two-thirds  of  the  distance  between  the  temporal  ridge  below 
and  the  midline  above. 

The  superior  frontal  convolution  covers  about  the  upper  one-third  of  the 
distance  from  the  median  line  above  to  the  temporal  ridge  below. 

The  superior  frontal  sulcus  passes  upward  from  the  supra-orbital  notch. 

The  inferior  frontal  sulcus  runs  just  below  the  temporal  ridge. 

The  first  or  superior  temporal  convolution  runs  along  the  lower  side  of 
the  fissure  of  Sylvius.      It  is  about  15  mm.   (f  in.)  wide. 

The  first  or  superior  temporal  sulcus  or  parallel  fissure  runs  parallel  to 
the  Sylvian  fissure  and  15  mm.  below. 

The  second  or  middle  temporal  convolution  is  wider  than  the  first  and  lies 
a  short  distance  abo\'e  the  level  of  the  base  of  the  skull. 

The  middle  temporal  sulcus  runs  close  above  the  zygoma. 

The  third  or  inferior  and  the  fourth  temporal  convolutions  lie  on  the  base 
of  the  brain,  separated  by  the  inferior  temporal  sulcus.  The  fourth  temporal  convo- 
lution has  on  its  inner  side  the  collateral  fissure  (see  Fig.  42). 

The  interparietal  sulcus  (pars  horizontalis)  leaves  the  postcentral  sulcus 
near  its  middle  and  passes  upward  and  backward  to  a  point  opposite  the  lambda. 

The  supramarginal  convolution  surrounds  the  termination  of  the  fissure  of 
Sylvius  and  is,  therefore,  under  the  parietal  eminence. 


42 


APPLIED   ANATOMY. 


The  angular  gyrus  surrounds  the  posterior  end  of  the  first  temporal  sulcus 
(parallel  fissure)  and  is,  therefore,  3  or  4  cm.  (i^  to  i)4  in.)  posterior  to  the 
parietal  eminence. 

The  transverse  occipital  sulcus  is  a  continuation  of  the  interparietal  sulcus 
to  just  beyond  the  parieto-occipital  fissure. 

The  lateral  occipital  sulcus  lies  close  to  the  tentorium;  it  divides  the  occipi- 
tal lobe  into  superior  and  inferior  convolutions.  (Sometimes  these  two  sulci  divide 
the  lobe  into  three  convolutions,  superior,  middle,  and  inferior.) 

The  Fissures  in  Children. — In  childhood  the  fissure  of  Rolando  is  somewhat 
more  vertical  than  in  adults;  the  fissure  of  Sylvius  has  its  point  of  division  a  little 
higher  and  runs  up  to  and  usually  above  and  in  front  of  the  parietal  eminence 
(Dana,  Med.  Record,  Jan.  1889,  p.  29).  After  the  age  of  three  years,  the  relative 
position  of  the  fissure  to  the  parietal  eminence  begins  to  approach  that  of  the  adult. 
(For  variations  due  to  age  see  Cunningham:  "  Contributions  to  the  Surface  Anatomy 
of  the  Cerebral  Hemispheres,"   1892.) 

The  objects  of  cerebral  topography  are  mainly  to  ascertain  in  case  of  injury  or  disease  of 
the  superficial  structures  what  parts  of  the  brain  beneath  are  liable  to  be  involved,  and  for  opera- 
tive procedures,  in  order  to  expose  the  affected  areas. 
The  convolutions  and  sulci  are  so  variable  that  all 
guides  are  only  approximate.  In  order  to  overcome 
this  defect  and  provide  for  unusual  conditions,  the 
openings  in  the  skull  are  usually  made  quite  large. 
The  flaps  of  scalp  and  bone  may  even  embrace  the 
entire  parietal  bone  or  a  quarter  of  one  hemisphere. 
As  regards  the  various  points — the  upper  Rolandic 
point  is  generally  conceded  to  be  15  mm.  {%,  to  ^  in.) 
posterior  to  the  midpoint  between  the  glabella  and 
inion.  The  angle  which  the  fissure  forms  with  the 
median  line  varies  from  64°  to  75°.  Cunningham 
gives  it  as  70°  and  Arthur  W.  Hare  as  67°.  Chiene's 
method  of  finding  the  desired  angle  is  usually  accepted 
as  reliable.  He  takes  a  square  piece  of  paper  and 
folds  it  obliquely  from  corner  to  corner  making  45°, 
and  then  folds  it  a  second  time  making  22>^°.  The 
two  being  added  together  give  67^^°  as  the  angle  made 
by  the  fissure  of  Rolando  with  the  anterior  portion  of 
the  longitudinal  fissure. 

The  pterion  was  placed  by  Broca  at  the  coronal  su- 
ture. This  is  15  mm.  (2  in. )  in  front  of  the  Sylvian  point.  In  several  formalin  hardened  brains,  we 
found  this  latter  to  be  at  the  posterior  angle  of  the  pterygoid  wing,  and  in  twenty  measured 
skulls  the  Sylvian  point  averaged  42  mm. 
(i^  in.)  behind  the  angular  process.  Reid 
placed  it  at  50  mm.  (2  in.) ,  which  we  think  too 
much.  Anderson  and  Makin  placed  it  at  i  >^  to 
2  in.  Thane  and  Godlee  placed  it  35  mm.  back 
and  12  mm.  up,  which  is  just  a  trifle  farther 
forward  than  we  have  located  it.  Landzert 
and  Heffler  gave  it  as  at  the  summit  of  union 
of  the  great  wing  of  the  sphenoid  with  the 
temporoparietal  suture,  as  we  have  given  it. 
When  prolonged,  the  Sylvian  fissure  some- 
times crosses  the  median  line  1.5cm.  {%  in.) 
above  the  parieto-occipital  fissure,  but  more 
usually  we  have  found  it  to  be  close  to  the 
fissure,  which  agrees  with  Reid.  The  parieto- 
occipital fissure  has  been  located  by  some 
authors  near  the  lambda,  but  we  would  place  it 
1.5  cm.  ( %  in.)  above.  We  believe  the  parie- 
tal eminence  to  be  a  fairly  reliable  guide  to  the 
posterior  extremity  of  the  fissure  of  Sylvius. 
Method  of  Anderson  and  Makin  for 
Locating  the  Fissures  of  the  Brain. — For  the  sake  of  comparison  the  following  method  of 
Wm.  Anderson  and  George  Henry  Makin  {four.  Anat.  and  Phys.,  vol.  xxiii,  1888-89,  p.  455)  is 


Fig.  51. — Chiene's  method  of  folding  a  square 
piece  of  paper  in  order  to  obtain  an  angle  of  67  J^ 
degrees. 


Fig.  52. — Method  of  Anderson  and  Makin  for  locating  the 
fissures  of  the  brain. 


THE   BRAIN. 


43 


given.  Draw  a  mid-  or  sagittal  line  from  opposite  the  highest  point  of  the  supra-orbital  arches 
to  the  external  occipital  protuberance.  From  the  midpoint  on  this  line  draw  another  to  the 
pre-auricular  point  at  the  level  of  the  upper  border  of  the  meatus.  This  is  the  frontal  line. 
From  the  most  prominent  point  of  the  external  angular  process  draw  a  line  to  the  junction  of 
the  middle  and  lower  thirds  of  the  frontal  line  and  prolong  it  i}4  in.  beyond. 

The  Sylvian  fissure  begins  between  i}i  and  ij4  in.  behind  the  angular  process  or  jroi 
the  distance  between  that  point  and  the  frontal  line.  The  bifurcation  is  ij^  to  2  in.  behind  the 
angular  process  or  yV  of  the  distance  between  it  and  the  frontal  line,  the  fissure  then  runs  to  an 
equal  distance  behind  the  frontal  line,  and  up  for  )4  in.  parallel  to  the  frontal  line.  The  fissure 
of  Rolando  runs  from  a  point  }i  in.  behind  the  midsagittal  point  to  one  ^  of  an  inch  in  front  of 
the  intersection  of  the  frontal  line  and  line  of  the  Sylvian  fissure.  The  parieto-occipital  fissure 
is  j"t  of  the  distance  from  the  midsagittal  point  to  the  inion.  It  lies  near  the  apex  of  the  lamb- 
doid  suture. 

The  Lateral  Ventricles. — The  lateral  ventricles  sometimes  become  distended  by  serous  or 
purulent  effusions  or,  as  in  apoplexy,  by  blood.     In  order  to  tap  them  Keen  ("  Reference  Hand- 


Fissure  of  Rolando 


Bregma 


Lateral  ventricle 


Middle  men- 
ingeal artery 
anterior 
branch 


Posterior  horn  of 
lateral  ventricle 


Inion' 


Lateral  sinus^ 


Middle  meningeal  artery,  posterior 
branch  ;  inferior  horn  of  lateral  ven- 
tricle seen  beneath 


Fig.  53. — Tapping  the  lateral  ventricles  and  trephining  for  cerebral  abscess.    Semidiagrammaticview  of  head,  show- 
ing relation  of  Rolandic  and  Sylvian  fissures  and  lines. 


book  of  the  Medical  Sciences,"  vol.  viii.,  p.  229)  has  given  three  points,  as  follows:  (i)  One- 
half  to  three-fourths  of  an  inch  (1.25  to  2  cm.)  on  either  side  of  the  median  line  and  one-third 
of  the  distance  from  the  glabella  to  the  upper  end  of  the  central  (Rolandic)  fissure.  This  is 
high  enough  to  avoid  the  frontal  air-sinuses  and  is  in  advance  of  the  motor  area.  A  grooved 
director  is  to  be  thrust  in  the  direction  of  the  inion.  The  ventricle  is  reached  at  a  depth  of  5  to 
6.5  cm.  (2  to  2>^  in.)  through  the  first  frontal  convolution.  (2)  Midway  between  the  mion 
and  upper  end  of  the  central  (Rolandic)  fissure  1.25  to  2  cm.  {}4  to  ^  in.)  from  the  median 
line.  The  director  is  to  be  thrust  toward  the  inner  end  of  the  supra-orbital  ridge  of  the  same 
side.  The  ventricle  will  be  reached  at  a  depth  of  5.5  to  7  cm.  {2%  to  234^  in.)  from  the  sur- 
face. (3)  Three  centimetres  {iX  in.)  behind  the  external  auditory  meatus  and  the  same  above 
Reid's  base  line  (from  the  lower  border  of  the  orbit  through  the  centre  of  the  external  auditory 
meatus).  The  director  is  to  be  Ihrust  toward  a  point  6.25  to  7.5  cm.  (2!^  to  3  in.)  directly 
above  the  opposite  external  meatus.  The  ventricle  will  be  reached  5  to  5.75  cm.  (2  to  2^'  in.) 
from  the  surface.  The  director  passes  through  the  second  temporal  convolution;  this  is  the 
preferred  method. 


44  APPLIED   ANATOMY. 

Spitzka  {New  York  Med.  Jour.,  Feb.  2,  1901,  p.  177)  has  pointed  out  how  these  ventricles 
vary  in  shape,  and  has  given  the  surface  relations  in  two  brains.  T.  T.  Wilson  {Jour.  Anat.  and 
Phys.,  vol.  xxviii,  1894,  pp.  228-235)  has  described  and  figured  them  in  three  drawings.  Spitzka 
states  that  the  ventricles  will  hold  about  60  c.c.  of  liquid. 

Cerebral  Abscess. — About  one-half  of  the  abscesses  of  the  brain  occur  from  disease  of  the 
middle  ear,  and  they  are  located  in  the  temporosphenoidal  lobe,  in  the  cerebellum,  or  between 
the  dura  and  petrous  portion  of  the  temporal  bone.  The  remainder  are  caused  either  by  blows 
or  infection  carried  to  the  part  in  infectious  diseases.  They  may,  therefore,  occur  anywhere  in 
the  brain. 

When  the  motor  areas  around  the  fissure  of  Rolando  are  involved,  the  location  of  the 
trouble  will  be  shown  by  spasm  or  paralysis  of  the  corresponding  muscles.  If  the  occipital  lobe 
is  affected  there  may  be  disturbance  of  sight,  as  hemiopia.  Involvement  of  the  frontal  lobes 
produces  mental  dulness,  and  if  of  the  third  left  frontal  gyrus,  or  Rroca's  convolution  there  may 
be  impairment  of  speech.  Disease  of  the  middle  lobe  of  the  cerebellum  may  be  accompanied 
by  a  staggering  gait.  In  many  cases  localization  symptoms  are  rare,  particularly  when  the 
abscess  is  small  and  located  in  the  temporosphenoidal,  parietal,  or  frontal  lobes  (see  chapter  on 
cerebral  localization). 

Trephining. — If  the  abscess  arises  from  middle-ear  disease,  it  is  customary  to  first  open 
the  mastoid  antrum  (see  chapter  on  ear)  and  then  by  removing  the  bone  above  to  explore  the 
surface  of  the  petrous  portion  of  the  temporal  bone.  To  explore  the  temporal  lobe  an  opening 
may  be  made  2.5  cm.  (i  in.)  above  the  external  auditory  meatus  and  a  needle  passed  inward, 
forward,  and  a  little  downward. 

To  reach  the  cerebellum,  the  trephine  should  be  applied  5  to  7  cm.  {2  to  2}{  in.)  behind 
the  external  meatus  and  well  below  the  superior  curved  line.  The  bone  at  this  point  is  apt  to 
be  thin  and  care  is  to  be  exercised  not  to  wound  the  membranes.  The  place  of  trephining  in 
abscesses  from  other  causes  is  to  be  decided  by  the  localizing  symptoms. 

THE   FACE. 

The  face  may  be  divided  into  the  regions  of  the  forehead,  temples,  ears,  eyes, 
nose,  viouth,  cheek,  and  upper  and  lower  jaws.  The  regions  of  the  eyes,  ears,  nose, 
and  mouth  will  be  considered  separately.  Owing  to  the  face  being  that  part  of  the 
body  most  open  to  scrutiny  and  most  difficult  of  concealment,  deformities  and  dis- 
figurements of  it,  resulting  from  injury  or  disease, — to  both  of  which  it  is  prone, — 
assume  a  greater  importance  than  the  same  troubles  elsewhere.  Therefore,  the 
anatomy  of  the  part  should  be  studied  with  regard  to  the  treatment  of  its  various 
aflections  from  a  cosmetic  as  well  as  from  a  curative  point  of  view.  What  is  usually 
regarded  as  constituting  the  face  embraces  the  anterior  half  of  the  head  as  \iewed 
from  the  front. 

The  Bones. — The  bones  of  the  head  have  been  divided  into  those  of  the 
cranium  and  those  of  the  face.  The  bones  of  the  cranium  are  eight  in  number,  viz. : 
the  frontal,  occipital,  two  temporals,  two  parietals,  the  sphenoid,  and  ethmoid.  The 
bones  of  the  face  are  fourteen  in  number,  of  which  twelve  are  in  pairs,  viz:  superior 
maxillary,  malar,  nasal,  palate,  lachrymal,  and  inferior  turbinated  bones — the  vomer 
and  inferior  maxilla  or  mandible  are  the  two  single  bones. 

From  this  it  will  be  seen  that  the  bony  framework  of  the  face  embraces  some  of 
the  bones  of  the  skull,  as  well  as  those  of  the  face  proper;  thus,  the  region  of  the 
forehead  is  formed  by  the  frontal  bone,  the  temporal  region  is  formed  by  the  frontal, 
parietal,  sphenoid,  and  temporal  bones,  all  belonging  to  the  cranium,  and  so  on. 
The  palate  bones  are  called  face  bones,  yet  they  are  placed  deep  in  the  region  of  the 
mouth  and  nose. 

The  Soft  Parts. — The  soft  parts  are  likewise  of  importance.  The  skin,  thin  in 
some  parts,  thick  in  others,  is  in  many  places  loosely  attached  and  has  inserted  in  it 
the  muscles  of  expression.      It  is  frequently  the  seat  of  disease,  particularly  of  cancer. 

On  each  side  of  the  face  are  the  parotid  glands,  often  the  site  of  inflammations. 

The  blood-vessels,  both  arteries  and  veins,  particularly  the  former,  are  very 
numerous  and  give  special  characters  to  wounds  and  diseases  of  the  face. 

The  nerves  are  abundant  and  complex.  They  are,  with  the  exception  of  the 
auricidaris  magnus,  which  comes  from  the  second  and  third  cervical,  and  to  a 
slight  extent  the  occipitalis  viinor  from  the  second  cervical,  all  derived  from  the 
cranial  nerves  and  are  both  motor  and  sensory.     The  paralyses  and  neuralgias  which 


THE  FACE. 


45 


affect  them  are  among  the  most  distressing   and  disfiguring   of  any  in  the  body, 
wounds  of  the  face  producing  paralysis  of  the  muscles  of  expression. 

The  relatively  small  size  of  the  face  in  relation  to  the  cranium  in  the  child  as 
compared  to  that  of  the  adult  has  already  been  alluded  to  (see  page  8).  The 
reasons  for  this  are  evident:  dentition  must  be  complete  to  insure  the  proper 
development  of  the  jaws;  the  use  of  the  special  senses  and  the  expression  of  the 
emotions  cause  the  facial  muscles  to  develop,  and  this  in  turn  causes  the  bones  to 
which  they  are  attached  to  become  more  rugged  in  outline  and  larger  in  size.  In 
old  age,  as  the  teeth  are  lost,  the  jaws  are  diminished  in  size  by  absorption  of  their 
alveolar  processes. 

THE   FRONTAL   REGION. 

The  frontal  region  embraces  that  part  of  the  face  above  the  eyes  and  nose  in 
front  and  anterior  to  the  temples  at  the  sides. 

The  Frontal  Suture. — The  frontal  bone  develops  from  two  centres  of  ossifi- 
cation, one  on  each  side.  These  unite  in  the  median  line  to  form  the  frontal  suture 
which  joins  the  anterior  fontanelle  and 
is  closed  about  the  same  time,  within  the 
age  of  two  years.  The  suture  occa- 
sionally persists  through  life  and  some- 
times the  line  of  junction  can  be  felt  in 
the  living;  it  should  not  be  mistaken 
for  fracture. 

The  frontal  eminences  in  the 
child  are  particularly  prominent,  the 
forehead  projecting  beyond  the  edge  of 
the  orbit.  This  makes  it  difficult  to 
apply  a  bandage  securely  to  the  head 
in  children  unless  it  is  twisted  to  draw 
in  its  sides. 

The  superciliary  ridges  are 
about  a  centimetre  above  the  edge  of 
the  orbit  over  its  inner  half.  Aided  by 
the  hair  of  the  eyebrows  they  serve 
to  divert  the  sweat  to  the  sides,  as 
pointed  out  by  Humphry.  They  are 
best  developed  in  the  adult  male. 
Directly  between  them  in  the  median 

line  on  a  level  with  the  upper  edge  of  the  orbit  is  a  depression  called  the  glabella. 
It  is  the  anterior  point  from  which  measurements  are  taken  in  cerebral  topography. 

Frontal  Sinuses. — Beneath  the  superciliary  ridges  are  the  frontal  air-sinuses, 
but  the  size  of  the  sinuses  is  not  necessarily  proportional  to  that  of  the  ridges;  they 
may  extend  quite  far  back  over  the  orbit.  Fractures  of  the  outer  wall  of  these 
sinuses  not  infrequently  occur  without  the  inner  table  being  injured.  A  septum 
separates  one  sinus  from  the  other,  not  always  in  the  median  line.  The  lining 
membrane  of  these  sinuses  is  often  inflamed  and  suppurates,  discharging  pus  into  the 
nose.      Tumors  also  grow  in  them. 

Margins  of  the  Orbit. — At  the  upper  and  outer  margin  of  the  orbit  is  the 
external  angular  process  of  the  frontal  bone.  The  line  of  junction  or  suture  between 
it  and  the  malar  bone  can  be  distinctly  felt  in  the  living  both  on  the  side  of  the  orbit 
and  on  the  side  toward  the  temple.  This  is  an  important  landmark  in  cerebral 
topography,  as  it  is  used  to  locate  the  fissure  of  Sylvius  and  also  the  middle  menin- 
geal artery.  On  the  upper  margin  of  the  orbit  at  about  the  junction  of  its  middle 
and  inner  thirds  is  the  sicpra-orbital  notch.  This  can  usually  be  readily  felt  through 
the  skin.  Sometimes  it  is  a  complete  foramen  instead  of  simply  a  notch.  It  is  then 
to  be  located  by  feeling  on  the  orbital  surface  just  behind  the  edge.  It  transmits 
the  supra-orbital  ner\-e  and  artery. 

The  supra-orbital  nerve,  a  branch  of  the  ophthalmic  division  of  the  fifth  nerve, 
is  sometimes  the  seat  of  neuralgia,  for  which  resection  of  the  nerve  is  performed. 


Fig.  54.— Frontal  region  of  a  child's  skull. 


46 


APPLIED   ANATOMY. 


The  pain  is  felt  above  the  orbit  radiating  from  the  supra-orbital  notch,  sometimes  as 
far  up  as  the  vertex.  Pain  is  also  felt  on  pressure  over  the  supra-orbital  notch.  If 
the  entire  ophthalmic  branch  of  the  fifth  nerve  is  affected,  pain  is  felt  in  the  eyeball 
and  down  the  side  of  the  nose.  The  incision  in  operating  may  be  made  at  the 
lower  border  of  the  eyebrow,  its  centre  being  over  the  notch.  If  the  notch  is  not 
readily  felt  on  the  edge  of  the  bony  orbit  at  the  junction  of  the  inner  and  middle 
thirds,  it  can  be  detected  by  feeling  with  the  tip  of  the  finger  on  the  orbital  surface. 
The  incision  is  made  through  the  fibres  of  the  orbicularis  palpebrarum,  corrugator 
supercilii,  and  frontalis  muscles,  then  through  the  palpebral  ligament  immediately 
below  the  bony  edge  of  the  orbit,  and  the  orbital  fat  separated  with  forceps;  the 
nerve  is  then  caught  with  a  hook  before  it  enters  the  notch,  and  brought  up 
and  removed.      Considerable   ecchymosis   may  follow  this  operation   if  the  accom- 

Branches  of  the  supra-orbital  nerve 


Fig.  55. — Supra-orbital  nerve  and  artery. 

panying  artery  is  divided.  Operations  on  the  ophthalmic  division  of  the  fifth  nerve 
have  usually  been  done  in  connection  with  removal  of  the  Gasserian  ganglion,  the 
other  branches  being  also  involved. 

Nasion. —  About  a  centimetre  below  the  glabella,  in  the  adult  skull,  is  the 
nasion,  or  line  of  junction  of  the  frontal  and  nasal  bones.  It  is  along  this  frontonasal 
suture,  to  one  side  of  the  median  line,  that  an  anterior  meningocele  is  apt  to  show 
itself. 

The  internal  angular  process  of  the  frontal  bone  articulates  with  the  nasal 
process  of  the  superior  maxilla  and  the  lachrymal  bones.  The  line  of  suture  is 
continuous  with  the  nasion  in  front  and  the  upper  edge  of  the  ethmoid  behind. 
Pus  originating  in  the  ethmoidal  cells,  frontal  sinuses,  and  lachrymal  apparatus  is  apt 
to  point  at  this  locality.     The  frontal  bone  is  a  favorite  seat  of  exostoses. 


THE  TEMPORAL   REGION. 

The  region  of  the  temple  is  on  the  side  of  the  head  as  far  forward  as  the  eye 
and  as  low  as  the  zygoma  and  infratemporal  crest.  The  floor  of  the  temporal  fossa 
is  formed  by  the  posterior  portion  of  the  frontal  and  anterior  portion  of  the  parietal 
bones  as  high  as  the  temporal  ridge,  the  outer  surface  of  the  greater  wing  of  the 
sphenoid,  and  the  squamous  portion  of  the  temporal  bone.  These  four  bones  meet 
to  form  the  region  of  the  pterion  (see  p.  39  and  42).  The  anterior  edge  of  the 
temporal  bone  overlaps  and  is  superficial  to  the  posterior  edge  of  the  sphenoid.    The 


THE  FACE. 


47 


an 


erior  edge  of  the  parietal  overlies  the  posterior  edge  of  the  frontal.  The  upper 
edges  of  the  temporal  and  sphenoid  overlap  the  lower  edges  of  the  frontal  and 
parietal  bones.  That  the  temporal  region  of  the  skull  is  distinctly  weaker  than  other 
regions  is  due  to  the  thinness  of  the  bones,  and  the  reason  that  fractures  here  are 
exceptionally  dangerous  is  on  account  of  the  middle  meningeal  artery  running 
through  a  canal  in  the  bone  in  this  region;  so  that  in  cases  of  fracture  the  artery 
is  torn  and  hemorrhage  occurs  above  the  dura,  which  causes  compression  of  the 
brain  (Fig.  56). 

The  infratemporal  crest  (crista  infratemporalis)  or  pterygoid  ridge  sep- 
arates the  temporal  region  above  from  the  pterygoid  region  below.  It  is  an  important 
landmark  in  operating  on  the  Gasserian  ganglion. 

A  spot  two  centimetres  behind  the  external  angular  process  and  slightly  above 
its  level  marks  the  anterior  extremity  of  the  fissure  of  Sylvius.      In  trephining  in  the 


Frontal 


Glabella 


External  angular 
process 


Parietal 


Anterior  branch,  mid- 
dle meningeal  artery 


Posterior  branch 
Infratemporal  crest 

Middle  meningeal 
artery  (running  up 
on  the  inside  of  the 
skull) 

Zygoma 


Sphenoid 

Fig.  56. — Frontal  and  temporal  regions  of  an  adult  skull. 


temporal  region  no  diploe  is  found  in  the  bones,  so  that  extreme  care  is  necessary 
to  avoid  wounding  the  dura  mater.  The  trephine  may  be  placed  4  cm.  ( i  ^  in. ) 
behind  the  external  angular  process  and  4.5  cm.  (i^  in.)  above  the  zygoma  to  strike 
the  middle  meningeal  artery.  This  will  be  level  with  or  a  little  above  the  highest 
part  of  the  edge  of  the  orbit. 

Temporal  Fascia. — This  is  the  dense  fascia  covering  the  temporal  muscle;  it 
is  formed  as  follows:  The  pericranium  as  it  comes  down  from  the  vault  of  the  skull 
and  reaches  the  temporal  ridge  passes  under  and  gives  attachment  to  the  temporal 
muscle.  The  temporal  fascia  consists  of  two  distinct  sheets  of  fascia,  the  superficial 
one  from  the  superior  temporal  ridge  being  attached  to  the  zygoma  below  and  to  the 
malar  bone  in  front;  the  deeper  layer  from  the  inferior  temporal  ridge  covers  the 
temporal  muscle,  and  a  short  distance  above  the  zygoma  divides  into  two  layers, 
one  of  which  is  attached  to  the  outer  edge,  and  the  other  to  its  inner  edge.  The 
upper  or  superficial  layer  of  the  temporal  fascia  leaves  the  bone  at  the  superior  tem- 
poral ridge  and  is  attached  below  to  the  top  of  the  zygoma,  blending  near  the  bone 
with  the  layer  beneath.  This  is  a  distinct  layer  though  not  always  readily  demon- 
strable in  dissections.  Between  the  layers  above  the  zygoma  is  some  fat  and  the 
orbital  branch  of  the  middle  temporal  artery.  Anteriorly  the  temporal  fascia  is. 
attached  to  the  posterior  border  of  the  malar  bone  and  the  temporal  ridge  of  the 
frontal.     The  temporal  fascia  is  tough  and  dense  and  gives  attachment  by  its  under 


48 


APPLIED   ANATOMY. 


Galea  aponeurotica 


Pericranium 


Sujjerficial 


Temporal  fascia 
superficial  laye 

Deep  laye: 


Temporal  muscle 


Superior  auricular 
muscle 


surface  to  the  temporal  muscle.  Abscess  occurring  under  the  temporal  fascia,  there- 
fore, does  not  tend  to  come  to  the  surface,  but  sinks  downward.  It  is  prevented 
from  making  its  exit  on  the  face  below  the  zygoma  by  the  parotid  gland  and 
masseter  muscle,  so  it  passes  inward  to  the  pterygoid  region  and  may  point  in  the 
throat  or  go  down  into  the  neck. 

The   occipitofrontal    aponeurosis,   or  galea   aponeurotica  as  it  approaches   the 
side  of  the  head  becomes  thinner  and  passes  down   to  insert  into  the  top  of  the 

zygoma  so  that  in  the  temporal 
region  the  layers  are  as  follows : 
Skin,  superficial  fascia,  galea 
ap07ieurotica,  two  layers  of 
the  temporal  fascia,  temporal 
muscle,  an  indistinct  perios- 
teum, and  bone.  Immediately 
above  the  zygoma  we  have  the 
deep  layer  of  the  temporal  fascia 
dividing  instead  of  a  single 
layer  as  is  the  case  higher  up. 
The  temporal  fossa  contains 
considerable  fat  which  dis- 
appears in  serious  illnesses. 
Disfiguring  depressions  are  also 
left  in  this  region  after  opera- 
tions involving  the  temporal 
muscle. 

The  temporal  artery  be- 
gins opposite  the  neck  of  the 
lower  jaw,  then  passes  over  the 
temporomaxillary  articulation, 
lying  on  its  capsule,  thence  over 
the  zygoma  about  a  centimetre 
in  front  of  the  ear.  It  lies  on 
the  temporal  fascia  and  about 
4  cm.  above  the  zygoma  divides 
into  an  anterior  and  posterior 
branch.  The  course  of  the 
temporal  artery  and  its  anterior 
branch  is  usually  quite  conspic- 
uous in  old  people  and  affords 
a  ready  means  of  ascertaining 
whether  or  not  the  arteries 
possess  the  calcareous  deposits 
characteristic  of  atheroma.  The 
location  of  the  artery  in  front 
of  the  ear  should  be  remem- 
bered, as  the  pulse  is  readily 
felt  there  in  the  administra- 
tion of  anaesthetics.  In  certain 
angiomas  of  the  scalp  the 
blood  supply  may  be  dimin- 
ished by  ligating  the  vessel  at 
that  point. 
The  temporal  muscle  receives  blood  from  the  middle  temporal  artery  which  comes 
from  the  temporal  and  perforates  the  temporal  fascia  just  above  the  zygoma,  and  from 
the  anterior  and  posterior  temporal  branches  of  the  internal  maxillary.  The  tem- 
poral fossa  is  frequently  the  seat  of  operations  to  expose  the  Gasserian  ganglion  and 
the  bleeding  from  these  various  temporal  arteries  contributes  to  their  gravity.  The 
auriculotemporal  nerve  lies  slighdy  posterior  to  the  artery  and  the  vein  in  front  of  it. 
They  are  not  important. 


Division  of  deep  layer 
of  temporal  fascia 


Orbital  branch  of 
temporal  artery 


Zygoma 


Pig.  57.— Transverse  coronal  section  in  the  region  of  the  temple,  show- 
ing the  various  layers. 


THE  FACE. 


49 


THE   REGION   OF   THE   CHEEK. 

In  this  region  we  may  include  the  parts  limited  above  by  the  zygoma,  in  front 
by  the  eye,  nose,  and  mouth,  below  by  the  lower  edge  of  the  lower  jaw,  and  behind 
by  the  ear.  The  soft  parts  of  the  cheek  are  supported  by  the  malar  and  superior 
and  inferior  maxillary  bones.  Between  the  skin  and  the  buccinator  muscle,  the 
hollow  beneath  and  in  front  of  the  malar  bone  and  masseter  muscle  is  filled  with  fat, 
sometiines  called  the  sucking  pad  or  cushion.  In  disease  this  fat  disappears,  hence 
the  hollow  cheek  of  invalids.  The  muscles  of  expression  are  superficial  to  this  fat 
and  have  their  insertion  in  the  skin.  Swelling  occurs  readily  from  contusions  and 
inflammations  because  the  tissues  of  the  cheek  are  lax.  Inflammations  may  either 
start  in  the  skin,  which  is  quite  prone  to  disease,  or  may  be  the  result  of  inflammation 
of  some  surrounding  structure,  as  the  parotid  gland,  the  roots  of  the  teeth,  the 
lachrymal  sac,  eyelids,  etc. 

The  skin  of  the  cheek  contains  numerous  sebaceous  and  sweat  glands.  It  is  a 
favorite  site  for  the  pustular  eruptions  of  infancy  and  childhood,  the  acne  of  youth. 


Opluhalmic  vein 


Ang-ular  artery 
Lateral  nasal 


Superior  coronary 


Inferior  coronary 
Inferior  labial 


Nasal  branch  of  ophthalmic 

Frontal  branch  of  ophthalmic 


Facial  artery 


Facial  vein 
Fig.  58. — -The  facial  artery  and  its  branches. 


and  the  non-malignant  as  well  as  the  cancerous  ulcers  of  the  aged.  It  is  also  the 
seat  of  noma  or  cancriim  oris.  This  starts  on  the  mouth  surface  as  a  gangrenous 
stomatitis  and  implicates  the  cheek,  causing  death  or  great  disfigurement  owing 
to  the  loss  of  cheek  substance.  Facial  carbuncle  or  malignant  pustule  occurs  on  the 
cheek,  or  sometimes  on  the  lips.      It  is  very  often  fatal. 

Wounds  and  contusions  of  the  cheeks  are  common,  and,  as  the  blood  supply  is 
abundant,  bleeding  is  free  and  healing  prompt.  On  account  of  the  insertion  of 
the  muscles  into  the  skin,  gaping  is  quite  marked. 

The  malar  bone  is  the  most  prominent  bone  of  the  cheek.  It  is  such  a 
strong  bone  and  so  strongly  supported  that  fracture  of  it,  as  well  as  that  of  the 
zygoma,  is  rare.  It  may  be  broken  by  direct  violence,  as  being  hit  with  a  stone,  etc. 
It  is  extremely  difificult  and  often  impossible  to  restore  the  fractured  parts  to  their 
original  level,  therefore  deformity  following  fracture  is  of  frequent  occurrence. 
The  fracture  may  involve  the  margin  of  the  orbit  and  cause  an  effusion  of  blood 
into  the  orbit,  pushing  the  eye- forward.  A  fracture  of  the  zvgoma,  if  very  much 
depressed,  may  interfere  with  the  use  of  the  temporal  muscle  below,  necessitating 
operation.      This  occurrence  is,  however,  rare. 


50 


APPLIED   ANATOMY. 


The  facial  artery  runs  upward  and  inward,  from  a  couple  of  centimetres  in  front 
of  the  angle  of  the  jaw,  along  the  anterior  border  of  the  masseter  muscle  to  the  angle 
of  the  mouth,  and  thence  to  the  inner  canthus  of  the  eye.  The  anterior  edge  of  the 
masseter  muscle  can  usually  be  distinctly  felt  beneath  the  skin.  At  this  point  the 
vessel  can  be  ligated  or  temporarily  compressed  by  passing  a  pin  beneath  it  and 
winding  a  silk  ligature  above  it,  around  the  ends  of  the  pin.  This  procedure  is 
desirable  in  some  operations  on  the  cheek,  as  angiomas  frequently  affect  this  region. 
If  the  facial  artery  is  ligated,  the  blood  supply  comes  from  the  superior  and  inferior 
coronary  arteries  of  the  opposite  side;  the  nasal  branch  of  the  ophthalmic,  anasto- 
mosing with  the  angular;  the  transverse  facial  below  the  zygoma,  from  the  temporal; 
the  infra-orbital,  a  branch  of  the  internal  maxillary  ;  and  to  a  slight  extent  from  the 
inferior  labial  and  others  still  less  important  (Fig.  58). 

The  internal  maxillary  artery,  one  of  the  terminal  branches  of  the  external 
carotid,  arises  in  the  parotid  gland  opposite  the  neck  of  the  lower  jaw.  This  is  just 
below  and  behind  the  articulation,  which  can  be  readily  felt  through  the  skin.      It 

Muscular  branches 
/ 


Infra-orbital 

\      Superior  alveolar 
(posteriordental) 


External  ptery- 
goid muscle 
Internal  ptery- 
goid muscle 


Superficial  temporal 

artery 

Sphenomandibular 

ligament' 

Middle  meningeal- 


External  carotid--' 
Inferior  alveolar  (dental) 


Buccal  nerve 


Lingual  nerve 


Inferior  alveolar 
iiL-rve 


F:g.  59. — 'I'he  internal  maxillary  artery. 

passes  between  the  bone  and  the  sphenomandibular  (long  internal  lateral)  ligament, 
then  between  the  two  pterygoid  muscles  or  between  the  two  heads  of  the  external 
pterygoid  muscle  to  the  posterior  surface  of  the  superior  maxillary  bone  in  the 
sphenomaxillary  fossa.  The  branches  of  its  first  part,  where  it  is  behind  the  neck  of 
the  jaw,  are  the  deep  auricular,  tympanic,  ')niddle  and  small  meniitgeal,  and  inferior 
alveolar  {dental).  The  branches  of  its  second  part,  as  it  passes  between  the  ptery- 
goid muscles,  are  all  muscular  :  they  are  the  masseteric,  pterygoid,  anterior  and 
posterior  deep  temporal,  and  the  buccal.  The  branches  of  the  third  portion  of  the 
artery,  in  the  sphenomaxillary  fossa,  are  the  posterior  dental,  infra-orbital ,  descending 
palatine.  Vidian,  pterygopalatine ,  and  sphoio-  or  nasopalatine. 

The  main  trunk  of  the  internal  maxillary  artery  is  not  often  involved  either  by 
injury  or  operations.  The  various  branches  are,  however,  of  considerable  impor- 
tance, as  they  supply  parts  which  are  often  the  site  of  operative  measures.  The 
importance  of  the  middle  meningeal  artery  in  reference  to  fractures  of  the  skull  has 
already  been  pointed  out.  The  inferior  alveolar  gives  rise  to  troublesome  hemorrhage 
when  the  lower  jaw  is  operated  on.  The  deep  temporal  branches  bleed  freely  when 
the  temporal  muscle  is  incised  in  operating  on  the  Gasserian  ganglion.  The  infra- 
orbital is  involved  in  operating  on  the  infra-orbital  nerve.  The  posterior  or  descending 
palatine  branch  descends  in  the  posterior  palatine  canal,  in  company  with  a  branch 


THE  FACE. 


51 


I 


from  Meckel's  ganglion,  to  emerge  on  the  roof  of  the  mouth  at  the  posterior  palatine 
foramen.      It  causes  free  hemorrhage  in  operating  on  cleft  palate. 

The  \'idian  and  pterygopalatine  branches  supply  mostly  the  roof  of  the  pharynx; 
they  bleed  when  adenoids  are  removed.  The  descending  and  sphenopalatine  sup- 
ply the  upper  part  of  the  tonsil  with  blood  and  may  give  rise  to  serious  hemorrhage 
in  the  removal  of  the  tonsils.  In  operating  on  Meckel's  ganglion,  bleeding  from 
these  vessels  is  free.  The  nasopalatine  runs  forward  in  the  nose  in  the  groove  on 
the  vomer.  It  is  often  the  cause  of  serious  nasal  hemorrhages  in  operations  on  the 
septum.  In  removal  of  the  upper  jaw,  bleeding  occurs  from  many  of  the  branches 
of  the  internal  maxillary,  but  it  is  hardly  so  free  as  might  be  expected,  especially  if 
the  external  carotid  has  been  previously  ligated. 

PAROTID  GLAND. 

The  parotid  gland  lies  on  the  cheek,  behind  the  jaw  and  below  the  ear.  The 
limits  (Fig.  60)  of  the  gland  are  important  because  suppuration  may  occur  in  any  por- 
tion of  its  structure.      Its  extent  is  as  follows  :    above  to  the  zygoma,  lying  below  its 


Superficial  temporal  artery 
Transverse  facial  artery 
Parotid  duct 


Facial  nerve 


Parotid  gland 


Auricularis 
magiius  nerve 


Submaxillary  gland 

Facial  artery  and  vein 
Fig.  60. — Parotid  gland  and  structures  of  the  side  of  the  face. 

posterior  two-thirds;  posteriorly,  to  the  external  auditory  canal,  the  mastoid  process, 
and  digastric  and  sternomastoid  muscles  ;  below  to  a  line  joining  the  angle  of  the  jaw 
and  mastoid  process  ;  and  in  front  about  half  the  width  of  the  masseter  muscle. 
This  latter  is,  however,  quite  variable. 

The  parotid  duct,  also  called  Stenson' s  duct,  leaves  the  upper  anterior  portion 
of  the  gland  about  a  centimetre  below  the  zygoma  and  runs  on  a  line  joining  the 
lower  edge  of  the  cartilaginous  portion  of  the  ear  with  the  middle  of  the  upper  lip. 
It  opens  on  a  papilla  on  the  inside  of  the  cheek  opposite  the  second  upper  molar 
tooth.  This  papilla  can  readily  be  seen  and  a  fine  probe  can  be  inserted  from  the 
mouth  into  the  duct;  thus  the  presence  of  a  calculus  may  be  detected.  In  operating 
on  the  cheek  the  line  of  this  duct  must  be  borne  in  mind,  as  wounding  it  may  cause 
a  salivary  fistula.  Wounds  of  the  lobules  of  the  gland  are  not  nearly  so  liable  to 
result  in  fistula  as  those  of  the  duct  itself. 


52  APPLIED    ANATOMY. 

Parotid  Fascia. — The  gland  is  covered  by  the  parotid  fascia.  This  fascia  is 
moderately  dense  and  is  continuous  with  the  fascia  separating  the  lobules  of  the  gland. 
Above  it  is  attached  to  the  zygoma  ;  in  front  it  is  continuous  with  the  masseteric 
fascia  over  the  masseter  muscle  ;  and  below  and  posteriorly  it  is  continuous  with  the 
deep  fascia  of  the  neck.  It  stretches  from  the  angle  of  the  jaw  to  the  sternomastoid 
muscle  and  somewhat  deeper  to  the  styloid  process  ;  the  band  running  from  the 
styloid  process  to  the  lower  jaw  is  called  the  stylomandibular  ligament.  From 
thence  it  is  continued  over  the  internal  carotid  artery  and  the  upper  surface  of  the 
internal  pterygoid  muscle. 

Lobes  of  the  Parotid  Gland. — The  gland  has  extentions  in  various  directions 
(Fig.  6i).  A  prolongation  behind  the  articulation  of  the  lower  jaw,  into  the  posterior 
portion  of  the  glenoid  cavity  immediately  in  front  of  the  external  auditory  canal,  is 
called  the  gleyioid  lobe.  Another  extension  winds  around  the  posterior  edge  of  the 
lower  jaw  on  the  lower  surface  of  the  internal  pterygoid  muscle  and  is  called  ih^  ptery- 

Glenoid 
lobe 

/  

■Socia  parotid  is 


Pterygoid  lobe 
Digastric  muscle  \  \ 

Carotid  lobe        External  carotid  artery 
Fig.  6i  — The  lobes  of  the  parotid  gland. 

goid  lobe.  A  prolongation  inward,  passing  between  the  external  carotid  on  the  outside 
and  the  styloid  process  and  the  internal  carotid  artery  on  the  inside,  is  called  the 
carotid  lobe.  A  separate  portion  of  the  gland,  sometimes  quite  detached,  lies  at  its 
upper  anterior  portion  between  the  zygoma  and  the  duct  of  Stenson;  it  is  called  the 
socia  parotidis. 

Vessels  and  Nerves  Traversing  the  Gland. —  The  external  carotid  artery 
enters  the  gland  to  divide  opposite  the  neck  of  the  lower  jaw  into  the  temporal  and 
internal  maxillary.  The  temporal,  before  it  leaves  the  gland,  gives  off  the  trans- 
verse facial  artery  which  runs  forward  on  the  face  between  the  zygoma  and  parotid 
duct.  It  is  usually  small  but  at  times  may  be  quite  large  and  even  go  over  to  the 
angle  of  the  mouth  and  form  the  two  coronary  arteries  (as  shown  in  M'Clellan's 
"Regional  Anatomy").  The  temporal  vein,  as  it  descends  into  the  gland,  is  joined 
by  the  internal  maxillary  vein  to  form  the  temporomaxillary  vein,  which,  after  it 
receives  the  posterior  auricular  vein,  goes  to  form  the  external  jugular. 

The  facial  nerve  emerges  from  behind  the  jaw  just  below  the  lobe  of  the  ear  and 
divides  into  its  various  branches  while  still  in  the  gland.  There  is  usually  a  large 
branch  passing  parallel  to  the  duct  of  Stenson  and  IdcIow  it.  The  auriculotemporal 
nerve  follows  the  temporal  artery,  emerging  from  the  gland  a  little  posterior  to  the 
artery.  Dr.  Skillern  has  shown  that,  by  injecting  it  with  cocaine,  operations  on  the 
walls  of  the  meatus  externus  for  furuncles,  etc. ,  can  be  rendered  painless.  The  auric- 
ularis  magnus  from  the  second  and  third  cervical  supplies  the  skin  over  the  gland. 


1 


THE  FACE. 


53 


Lymphatic  nodes  are  found  both  on  the  gland  and  in  its  substance.  These  may 
be  involved  in  general  disease  of  the  cervical  lymphatics. 

Affections  of  the  Parotid  Gland. —  The  duct  may  be  affected  with  calculus, 
as  already  mentioned.  As  the  opening  of  the  duct  at  the  papilla  is  smaller  than  the 
lumen  of  the  canal  farther  back,  calculi  are  apt  to  lodge  close  to  the  anterior  extrem- 
ity. They  are,  therefore,  readily  felt  and  removed  by  incision  on  the  inside  of  the 
mouth.     The  gland  proper  is  subject  to  inflammations  and  tumors. 

Simple  parotiditis  or  viiunps  really  is  an  infectious  inflammation,  nevertheless,  it 
rarely  suppurates.  Siippiirative  parotiditis  may  occur  from  infected  wounds  or  arise 
in  the  course  of  the  eruptive  fevers,  etc.  In  inflammation  of  the  gland,  pain  and 
swelling  are  important  symptoms.  The  pain,  which  is  considerable,  is  not  due  so 
much  to  the  so-called  dense  parotid  fascia  covering  the  gland,  for  this  is  only 
moderately  thick,  as  it  is  to  the  fact  that  the  gland  is  of  a  racemose  type  and  the 


Branches  of 
facial  nerve 


Temporal  artery 

Parotid  duct 


Auricularis 
niagiius  nerve 


'Jugular  vein 

External  carotid 
artery 


Fig.  62.— Structures  in  relation  with  the  parotid  gland. 

fibrous  septa  between  the  lobules  are  abundant  and  prevent  free  expansion  of  the 
contained  lobules.  Expansion  is  also  hindered  by  the  peculiar  location  of  the  various 
parts  of  the  gland.  SweUing  of  the  glenoid  lobe  produces  pain  in  the  ear  and  also  in 
the  temporomaxillary  articulation.  Swelling  of  the  carotid  and  pterygoid  lobes 
causes  pain  and  fulness  in  the  throat.  Opening  the  lower  jaw  reduces  the  space 
posterior  to  it  in  which  the  gland  lies  and  pinches  it  against  the  bony  meatus  and 
mastoid  process,  so  that  it  is  impossible  to  open  the  jaw  widely. 

If  suppuration  occurs  it  is  liable  to  progress  from  one  lobule  to  another;  when 
this  is  the  case  comparatively  small  abscesses  may  appear  in  different  parts  of  the 
gland  with  unaffected  tissue  between  them.  As  an  abscess  heals  in  one  lobule,  sup- 
puration is  apt  to  occur  in  another,  consequently  the  disease  may  persist  for  a  long 
time.  More  rarely  in  the  course  of  or  following  infectious  diseases,  particularly  in 
debilitated  patients,  considerable  portions  of  the  gland  may  slough.  This  form  is  apt 
to  be  fatal.  If  the  suppurating  focus  is  confined  to  lobules  which  are  deeply  placed, 
the  diagnosis  may  be  obscure  because  it  is  difficult  to  localize  the  affected  spot.  If, 
however,  it  is  near  the  surface  of  the  gland,  the  pus  does  not  tend  to  extend  sideways, 
the  fibrous  septa  prevent  this,  but  it  tends  to  work  its  way  up  and  perforate  the  skin. 
If  the  glenoid  lobe  is  affected,  the  pus  may  find  an  exit  through  the  external  auditory 
meatus  or  even  involve  the  temporomaxillary  joint.     If  the  carotid  or  pterygoid  lobes 


54 


APPLIED    ANATOMY. 


are  affected,  the  pus  may  go  between  the  pterygoid  muscles,  or  around  the 
internal  carotid  artery  and  project  and  open  into  the  pharynx.  It  may  also  break 
into  the  carotid  artery  or  jugular  vein,  or  perforate  through  the  fascia  below  and 
go  down  the  neck.  Large  abscesses  and  sloughs  may  be  followed  by  a  parotid 
fistula. 

Lines  of  Incision  for  Abscess. — The  manner  of  opening  a  parotid  abscess 
depends  on  its  location  and  size.  If  it  is  desired  to  open  an  abscess  anterior 
to  a  point  1.5  cm.  or  about  half  an  inch  in  front  of  the  ear,  the  structures  to  be 
avoided  are  the  duct  and  facial  nerve.  The  incisions  are  to  be  made  parallel 
to  the  zygoma,  and  the  duct  is  to  be  avoided  by  not  cutting  on  a  line  joining 
the  lower  edge  of  the  cartilage  of  the  ear  with  the  middle  of  the  upper  lip.  The 
branches  of  the  facial  nerve  lie  deep  and  are  to  be  avoided  by  making  the 
incision  parallel  to  their  course  and  not  extending  it  too  deeply.     After  incising 

the  skin,  the  deeper  tissues  may  be  sepa- 
rated by  introducing  a  pointed  pair  of  haemo- 
static forceps  and  opening  the  blades.  In 
operating  in  the  region  below  the  ear,  the 
blood-vessels  are  to  be  avoided.  To  do 
this  incise  the  skin  longitudinally,  not  trans- 
versely, and  open  the  deep  parts  carefully 
with  the  haemostatic  forceps,  as  already 
described.  Another  method,  when  the  ab- 
scess is  farther  forward,  is  to  make  a  hori- 
zontal incision  rather  low  down  on  the 
angle  of  the  jaw  and  then  introduce  a 
grooved  director  or  haemostatic  forceps  from 
below  upward. 

Tumors  of  the  parotid  gland  are  liable 
to  be  mixed  in  character,  with  a  sarcoma- 
tous element.  They  are  often  fairly  cir- 
cumscribed and,  particularly  if  they  do 
not  involve  the  parotid  duct,  can  be  re- 
moved comparatively  readily.  If  they  are 
malignant  and  large,  complete  removal  is 
practically  impossible.  The  possibility  of 
parotid  fistula  and  paralysis  of  the  facial 
nerve  following  operation  on  this  gland  should  always  be  borne  in  mind  and  explained 
to  patients.  The  presence  of  facial  paralysis  is  indicative  of  malignancy  (see  Fig.  63). 
'I'he  parotid  lymph  nodes  on  or  beneath  the  capsule  may  become  enlarged  and 
inflamed  and  resemble  true  parotiditis.  There  is  one  node  just  below  the  zygoma 
and  in  front  of  the  ear  that  is  not  infrequently  enlarged  in  strumous  children.  This 
is  apt  to  be  involved  when  affections  of  the  lids  or  scalp  are  present.  In  open- 
ing abscesses  of  these  nodes  there  is  little  likelihood  of  injuring  either  the  nerve  or 
the  duct,  because  the  nodes  are  superficial.  The  transverse  facial  artery  is  usually 
too  small  to  cause  trouble.  The  possibility  of  its  supplying  the  coronary  arteries 
of  the  lips,  as  already  described,  in  which  case  it  would  be  very  large,  should  be 
remembered. 

THE   UPPER   JAW. 

The  upper  jaw  carries  the  upper  teeth  and  contains  the  maxillary  sinus  or 
antrum  of  Highmore.  The  afiections  of  the  antrum  will  be  alluded  to  in  the  chapter 
on  the  nose  (see  page  103).  Fractures  of  the  superior  maxilla  involve  the  nasal 
process,  the  alveolar  process,  or  pass  transversely  through  the  body  of  the  bone. 
The  nasal  process  is  sometimes  broken  in  fractures  of  the  nose.  In  this  injury,  the 
lachrymal  canal  and  sac  may  be  injured  and  the  flow  of  tears  through  them  pre- 
vented, causing  the  tears  to  run  over  the  cheek. 

Fractures  of  the  alveolar  process  are  common  enough  as  a  result  of  blows  and 
extracting  teeth.  These  fractures,  as  they  communicate  with  the  mouth  through  the 
broken  gums  or  mucous  membrane  or  tooth  socket,  are  necessarily  compound,  and 


Fig.  63. — Malignant  tumor  of  the  parotid  gland 
producing  facial  paralysis  (author's  case). 


THE    FACE. 


55 


consequently  become  infected  from  the  mouth  and  suppurate.  This  may  cause 
necrosis  of  the  fragment,  but  the  blood  supply  of  the  jaws  is  so  good  that  death  of 
a  fragment  is  rare,  and  it  is  not  customary  to  remove  fragments  not  completely 
detached.     The  front  wall  is  sometimes  driven  in. 

Fractures  occasionally  occur  in  which  the  line  passes  through  one  or  both 
superior  maxillary  bones  from  below  the  malar  bone  into  the  nose.  If  this  fracture 
passes  completely  backward,  it  detaches  the  lower  portion  of  the  palate  bone  and 
pterygoid  processes  of  the  sphenoid  bone.  The  fragment  in  such  cases  has  a 
tendency  to  slip  backward.  It  can  be  replaced  by  inserting  a  hook  through  the 
mouth  and  behind  the  soft  palate  and  pulling  the  fragment  forward.  This 
injury  is  produced  by  a  blow  on  the  anterior  portion  of  one  or  both  bones, 
passing  downward  and  backward.  In  order  to  determine  the  existence  of  fract- 
ure, Guerin  recommended  inserting  the  finger  in  the  mouth  and  feeling  for  the 
pterygoid  plates.  The  hamular  process  of 
the  internal  pterygoid  plate  can  readily 
be  felt  about  one  centimetre  above  and 
behind  the  last  upper  molar  tooth.  Fract- 
ures in  the  neighborhood  of  the  first  and 
second  molar  teeth  are  liable  to  open  the 
antrum,  as  the  roots  of  these  teeth  project 
into  it. 

Resection  of  Upper  Jaw. — Tumors 
of  the  antrum  may  necessitate  a  resection 
of  the  superior  maxilla  of  one  side.  Hey- 
felder  was  the  first  to  remove  both  superior 
maxillae,  in  1844:  this  was  before  the  dis- 
covery of  anaesthesia.  In  removing  one 
superior  maxilla,  the  incision  known  as  Fer- 
giisson's  is  used.  This  is  made  through 
the  middle  of  the  upper  lip,  around  the  ala 
of  the  nose  to  the  inner  canthus  of  the  eye, 
thence  outward  along  the  lower  border  .of 
the  orbit  to  the  malar  bone.  The  bleeding 
from  this  incision  is  free.  The  coronary 
arteries  should  be  looked  for  near  the 
mucous   surface  of   the   lip  toward  its  free 

edge.  Bleeding  will  also  occur  from  the  lateralis  nasi  and  the  angular  arteries. 
The  soft  parts  are  raised  from  the  bones  as  far  back  as  the  masseter  muscle. 
This  is  just  about  level  with  the  outer  edge  of  the  bony  orbit.  In  doing 
so  the  infra-orbital  nerve  and  artery  will  be  divided.  The  artery  is  not  large 
but  may  bleed  freely.  The  fibrous  floor  of  the  orbit  is  raised  and  the  attach- 
ment of  the  inferior  oblique  muscle  loosened.  The  malar  bone  is  sawed  downward 
and  outward  opposite  the  sphenomaxillary  fissure,  and  the  division  completed  with 
forceps.  The  nasal  portion  of  the  superior  maxilla  is  sawed  through  from  the  orbit 
into  the  nose.  The  soft  parts  of  the  roof  of  the  mouth  are  divided  in  the  median 
line  to  the  posterior  edge  of  the  hard  palate,  and  thence  along  its  edge  to  the  last 
molar  tooth.  The  soft  palate  is  firmly  attached  to  the  hard  palate  and  has  to  be 
detached  with  scissors.  An  incisor  tooth  is  then  drawn,  and  the  bony  palate  sawed 
through  from  the  nose  into  the  mouth.  The  bone  with  the  tumor  is  wrenched  loose 
with  lion-jawed  forceps.  The  union  between  the  posterior  portion  of  the  superior 
maxilla  and  the  pterygoid  processes  of  the  sphenoid  is  not  bony,  but  fibrous,  so  that 
the  bone  is  torn  away  from  the  processes  and  the  latter  are  left  behind.  As  the  bone 
comes  away,  the  maxillary  nerve  should  be  cut.  The  bleeding  which  follows  is  from 
the  infra-orbital,  superior  alveolar  (posterior  dental),  and  posterior  palatine  arteries, 
branches  of  the  internal  maxillary.  It  is  not  so  free  as  might  be  expected,  provided 
preliminary  ligation  of  the  external  carotid  has  been  performed.  It  will  be  observed 
that  the  facial  nerve  is  not  touched  nor  is  the  parotid  duct  wounded. 

Neuralgia  of  the  Maxillary  Nerve. — The  pain  involves  the  cheek  from  the 
eye  to  the  mouth  and  as  far  forward  as  the  median  line,  also  the  upper  gums  and 


Fig.  64. — Resection  of  the  upper  jaw.  The 
curved  lines  indicate  the  skin  incision  and  the 
straight  Hnes  where  the  bones  are  to  be  divided. 


56  APPLIED   ANATOMY. 

hard  palate.  The  operations  devised  for  its  I'elief  are  both  numerous  and  intricate, 
and  necessitate  an  accurate  anatomical  knowledge  of  the  ])arts.  The  maxillary 
nerve  is  the  second  division  of  the  fifth  cranial  nerve.  It  leaves  the  skull  cavity  by 
the  foramen  rotundum,  then  crosses  the  sphenomaxillary  fossa,  enters  the  spheno- 
maxillary fissure  and  infra-orbital  canal  to  emerge  on  the  cheek,  opposite  the  middle 
of  the  lower  edge  of  the  orbit  and  about  6  mm.  below  it.  The  intracranial  portion 
is  6  to  8  mm.  in  length.  From  the  sphenomaxillary  fossa  to  the  infra-orbital  fora- 
men is  about  5  cm.  (2  in.  ).  Its  branches  are  as  follows:  one  or  two  small  branches 
to  the  dura  mater,  the  orbital  or  sphenomalar  branch  to  the  cheek  and  anterior  tem- 
poral region,  spheyiopalatine  bra7iches  going  to  Meckel's  ganglion,  the  posterior, 
middle,  and  anterior  dental  to  the  upper  teeth,  and  the  terminal  branches,  labial, 
nasal,  and  palpebral,  on  the  face. 

Its  anterior  portion  has  been  removed  through  an  incision  on  the  face,  and  its 
posterior  portion  with  Meckel's  ganglion  has  been  operated  on  either  anteriorly 
through  the  maxillary  sinus  or  laterally  through  the  temporal  fossa,  after  removing 
the  zygoma.  The  writer  has  removed  the  intracranial  portion  by  entering  the  ante- 
rior cerebral  fossa  through  the  temporal  region.    Removal  of  the  infra-orbital  portion 


^  ..^J^^^i^  ^''"■'•Br^v  ^^^""^  Infra-orbital  nerve 

breaking  into  branches 


Infra-orbital  artery 


Fig.  65. — Exposure  of  the  infra-orbital  nerve  and  artery. 

of  the  nerve  is  so  liable  to  be  followed  by  recurrence  of  the  pain  and  interferes  so 
much  with  the  more  complete  procedures,  as  it  destroys  the  guide  (the  nerve  itself) 
which  leads  the  operator  to  Meckel's  ganglion,  that  it  is  doubtful  whether  it  should 
ever  be  resorted  to.  The  posterior  dental  branches  are  given  off  so  far  back  that 
they  are  not  apt  to  be  removed  in  this  operation. 

Removal  of  the  Infra-orbital  Nerve. —  An  incision  3  cm.  in  length  is  made 
along  the  lower  edge  of  the  orbit.  This  divides  the  orbicularis  palpebrarum  muscle. 
Arising  from  the  bone,  between  the  infra-orbital  foramen  and  the  edge  of  the  orbit, 
is  the  levator  labii  superioris  muscle.  This  should  be  carefully  detached,  and  the 
foramen  with  its  artery  and  nerve  will  be  found  opposite,  the  middle  of  the  lower  edge 
of  the  orbit  and  about  6  mm.  {y^  in.  )  below  it,  on  a  line  drawn  from  the  supra-orbital 
notch  to  between  the  premolar  teeth.  The  position  of  the  foramen  having  been 
located,  the  palpebral  ligament  and  periosteum  are  divided  and  the  contents  of  the 
orbit  raised.  The  canal  is  next  to  be  opened.  This  can  be  done  either  by  chiselling 
away  its  roof  from  the  opening  on  the  face  and  following  it  backward  or  by  breaking 


THE  FACE. 


57 


through  its  upper  wall.  This  latter  procedure  is  liable  to  give  trouble,  because  if 
the  track  of  the  canal  is  not  encountered  the  instrument  breaks  into  the  maxillary- 
sinus,  the  roof  of  which  is  very  thin.  The  infra-orbital  canal  does  not  pass  directly 
backward  but  backward  and  outward,  striking  the  sphenomaxillary  fissure  about  2 
cm.  (in  a  large  skull)  behind  its  anterior  extremity.  Sometimes  the  roof  of  the 
canal  is  fibrous,  in  which  case  the  groove  so  formed  can  be  readily  felt,  but  in  others 
it  is  bony.  The  nerve  is  hooked  up  and  cut  as  far  back  as  one  can,  so  as  to  remove, 
if  possible,  the  posterior  dental  branches.  The  terminal  branches  are  then  pulled  off 
from  the  cheek,  and  the  nerve  drawn  out  from  the  front.  It  is  in  the  highest  degree 
desirable  to  avoid  wounding  the  artery,  as  death  is   said  to  have  followed  it,  and 


4th  nerve 


Ophthalmic  branch — 5lh  nerve 
Motor  root 

Sensory  root 

Maxillary  branch 

Gasserian  ganglion 


Meckel's  ganglion 


Infra-orbital 
nerve  and  artery 


Middle  meningeal  artery 
Mandibular  branch 
Temporomalar  n^rve 


Buccal  branch 

Stump  of  external 
pterygoid  muscle 

Lingual  nerve 

Inferior  alveolar 
nerve  and  artery 


_  Internal  pterygoid 
muscle 


Fig.  66.— The  fifth  or  trifacial  nerve  with  its  various  branches. 


there  may  be  bleeding  into  the  orbit,  causing  protrusion  of  the  eye  and  serious  inter- 
ference with  its  sight.  A  better  way  of  removing  the  nerve,  the  method  of  Thiersch 
(  Verhand.  der  Deidschen  Gesell.  fiir  Chir.,  18  Congress,  Berlin,  1889,  p.  44),  is  to 
grasp  it  with  a  pair  of  slender,  curved  forceps,  then  by  rotating  the  forceps  very 
slowly  (about  i  turn  a  minute)  both  the  distal  and  proximal  ends  are  wound  around 
it  and  an  extremely  long  portion  of  the  nerve  can  be  removed. 

Removal  of  Meckel's  Ganglion,  —  Operating  from  the  froyit  through 
the  maxillary  sinus  (Carnochan's  operation,  or  removal  of  the  sphenopalatine 
(Meckel's)  ganglion  and  maxillary  nerve). — The  incision  is  V-shaped,  the  apex 
being  2  cm.  above  the  angle  of  the  mouth,  and  the  branches  3  cm.  long.  This  flap 
should  consist  of  all  tissues  down  to  the  bone.  The  bleeding  will  be  free,  as  the 
facial  vein  and  branches  of  the  facial  artery  will  be  cut.  As  the  infra-orbital  foramen 
is  reached,  the  nerve  is  detached  from  its  under  surface.     The  anterior  wall  of  the 


58  APPLIED   ANATOMY. 

maxillary  sinus,  which  is  quite  thin,  is  broken  with  a  chisel  for  an  extent  of  2  cm. 
The  infra-orbital  canal  is  opened  from  below,  from  the  surface  clear  back  to  the  pos- 
terior wall  of  the  sinus.  The  infra-orbital  nerve  is  then  brought  down  into  the  sinus 
to  serve  as  a  guide  to  the  foramen  rotundum.  Care  should  be  taken  (by  opening 
the  canal  with  comparatively  blunt  instruments)  not  to  wound  the  infra-orbital  artery. 
Then  break  a  hole  in  the  posterior  wall  of  the  sinus.  This  is  very  thin,  and  not  over 
half  a  centimetre  (i  in. )  intervenes  between  it  and  the  anterior  wall  of  the  sphenoidal 
sinus,  so  that  care  should  be  taken  not  to  drive  the  chisel  too  far  back.  The  pos- 
terior wall  having  been  broken  with  the  chisel  and  the  pieces  picked  away,  the  nerve 
is  dragged  downward,  freed  as  far  back  as  possible,  and  pulled  loose.  Traction  on 
the  nerve  brings  the  ganglion  forward,  and  with  forceps  it  is  then  drawn  out.  The 
bleeding,  after  breaking  through  the  posterior  wall  of  the  sinus,  may  be  very  free. 
Meckel's  ganglion  lies  in  the  sphenopalatine  fossa  just  below  the  maxillary  nerve 
after  it  leaves  the  foramen  rotundum.  Two  short  branches  unite  the  ganglion  and 
nerve.  It  is  here  that  the  internal  maxillary  artery,  in  the  third  part  of  its  course, 
divides  into  six  branches:  the  infra-orbital  and  posterior  de?ital,  the  posterior  or 
descending-  palatitie  and  Vidian,  and  the  pterygopalatine  and  spheno-  or  nasopalatine 
arteries.  If  these  arteries  are  wounded,  as  they  are  very  apt  to  be,  the  bleeding  is 
very  free.  To  control  it  temporary  packing  is  at  first  resorted  to.  If  it  persists,  the 
nerve  is  removed  as  well  as  possible  and  the  bleeding  stopped  with  gauze.  This 
may  be  firmly  packed  into  the  opening  through  the  posterior  wall  at  the  upper  inner 
portion  of  the  sinus,  but  care  should  be  taken  not  to  push  it  roughly  through  the 
fossa  and  into  the  sphenoidal  sinus  (or  cells)  beyond. 

J.  D.  Bryant  {^Operative  Surgery,  vol.  i,  p.  243)  in  cases  of  severe  hemorrhage 
advises  the  prompt  ligation  of  the  external  carotid  artery,  a  procedure  not,  however, 
often  required.  It  has  been  suggested  that  instead  of  making  the  incision  on  the 
cheek  to  make  it  in  the  mouth  above  the  gums,  and  pull  the  cheek  and  mouth 
upward  and  outward.  This  procedure,  while  obviating  the  scar,  makes  the  opera- 
tion somewhat  more  difficult.  Kocher  resects  the  malar  bone  with  the  outer  wall  of 
the  sinus  and  turns  it  up,  bringing  it  back  into  place  on  the  completion  of  the 
operation. 

Operating  from  the  Side  Through  the  Pterygoid  Fossa. — Both  the 
maxillary  and  mandibular  branches  have  been  reached  by  this  route;  the  former  at 
the  foramen  rotundum  and  the  latter  at  the  foramen  ovale.  Liicke,  of  Strasburg, 
was  the  pioneer  of  the  operation  on  the  maxillary  nerve,  and  Joseph  Pancoast,  of 
Philadelphia,  on  the  mandibular.  Liicke' s  operation  was  modified  by  Lossen,  of 
Heidelberg.  Recently,  Mixter,  of  Boston,  has  again  advocated  the  method.  A 
convex  flap,  base  down  and  reaching  y^  inch  below  the  zygoma,  is  cut  from  the 
external  margin  of  the  orbit  to  the  lobe  of  the  ear.  The  zygoma  is  sawed  through, 
and,  with  the  masseter,  pulled  downward.  Maurice  Richardson,  in  describing  Mix- 
ter's  operation  { Internal.  Textbook  of  Surg.,  vol.  i,  p.  863),  says  that  "if  the 
operator  is  skilled  enough  in  the  subsequent  manipulations,  he  may  omit  cutting  the 
temporal  muscle."  It  will  be  easier,  however,  to  divide  the  coronoid  process  and 
turn  the  temporal  muscle  upward,  clearly  exposing  the  infratemporal  crest.  Detach 
the  upper  head  of  the  external  pterygoid  muscle  and  push  it  downward,  exposing 
the  external  pterygoid  plate.  Chisel  ofT  the  spur  at  the  anterior  extremity  of 
the  infratemporal  crest,  and  immediately  in  front  and  to  the  inner  side  is  the  supe- 
rior maxillary  nerve,  with  the  terminal  portion  of  the  internal  maxillary  artery 
just  below  it.  Immediately  posterior  to  the  root  of  the  pterygoid  plate  is  the 
foramen  ovale  and  mandibular  nerve,  with  the  middle  meningeal  artery  a  little 
posterior  to  it. 

Anatomical  Comments. — The  incision  at  its  posterior  extremity  can  be 
made  to  avoid  cutting  the  temporal  artery  by  feeling  its  pulsations,  about  a  centimetre 
or  less  in  front  of  the  ear,  as  it  passes  over  the  zygoma.  The  incision  should  not 
involve  the  deep  structures — only  the  skin  and  superficial  fascia.  Therefore,  the 
facial  nerve  and  parotid  duct  (a  finger's  breadth  below  the  zygoma)  will  not  be 
injured. 

In  clearing  the  upper  surface  of  the  zygoma,  it  will  be  necessary  to  cut  through 
the  layers  of  the  temporal  fascia;    between  them  the  orbital  branch  of  the  temporal 


THE  FACE. 


59 


artery  may  be  encountered  and  may  bleed.  The  temporal  muscle  arises  not  only 
from  the  deep  layer  of  the  temporal  fascia,  but  may  also  be  attached  anteriorly  to 
the  inner  surface  of  the  zygoma,  and  in  loosening  it  free  bleeding  from  the  deep 
temporal  arteries,  branches  of  the  internal  maxillary,  may  be  encountered.  No 
trouble  need  be  expected  in  sawing  through  the  anterior  end  of  the  zygoma,  but  care 
should  be  taken  not  to  injure  the  parotid  duct,  or  the  socia  parotidis  if  it  is  present. 
In  making  the  division  of  the  posterior  end  of  the  zygoma,  one  must  guard  against 
opening  the  temporomaxillary  articulation,  for,  when  the  head  of  the  mandible  is 
back  in  the  glenoid  fossa,  the  capsule  of  the  joint  extends  considerably  in  front  of  it. 
Therefore,  it  is  better  to  open  the  mouth  and  push  the  jaw  on  that  side  forward  until 
it  rides  on  the  eminentia  articularis,  then  the  anterior  limit  of  the  joint  can  be  recog- 
nized and  avoided.  Before  one  can  reach  the  spur  on  the  anterior  extremity  of  the 
infratemporal  crest, "  the  temporal   muscle  must  be  detached  from  the   bone.      The 


Processus  coronoideus 


Temporalis 


Crista  infratempo- 
ral is 


Spur 


N.  maxillaris 


A.   infra-orbitalis 
A.  temporalis 
profundus 
A.  alveolaris 
posterior 
A.  maxillaris 
internus 


N.  mandibularis 

M.  pterygoideus  ex- 

ternus.    Upper  head 

turned  down 

Masseter 


Zygoma 


Fig.  67.— Operating-  through  the  pterygoid  fossa.  The  skin  with  the  zygoma  and  masseter  have  been  turned 
down.  The  coronoid  process  is  divided  and  turned  up.  The  upper  head  of  the  external  pterygoid  has  been 
detached  and  turned  down.  The  maxillary  nerve  is  in  front  of  the  pterygoid  plate  (processus  pterygoideus)  and 
the  mandibular  nerve  and  middle  meningeal  artery  just  behind  it. 

upper  head  of  the  external  pterygoid  muscle  arises  from  the  bone  just  below  the 
pterygoid  ridge  (infratemporal  crest),  and  must  be  loosened  from  the  bone  to  obtain 
access  to  the  nerves  (see  Fig.  67). 

The  coronoid  process  rises  almost  as  high  as  the  infratemporal  crest,  and,  there- 
fore, in  order  to  gain  space  it  will  be  necessary  to  depress  the  jaw.  Running  upward 
and  inward  over  the  internal  pterygoid  muscle,  and  passing  just  in  front  of  the  origin 
of  the  upper  head  of  the  external,  is  the  internal  maxillary  artery  and  pterygoid 
plexus  of  veins.  These  vessels  lie  directly  below  the  maxillary  nerve  as  it  crosses 
the  sphenopalatine  fossa,  and  it  is  to  be  expected  that  free  hemorrhage  will  accom- 
pany the  attempt  to  fish  out  the  nerve. 

In  operating  in  this  region,  one  surgeon  found  the  bleeding  so  severe  as  to 
require  the  ligation  of  the  external  carotid  artery. 

Intracranial  operations  are  hardly  ever  done  for  maxillary  neuralgia  alone.  The 
mandibular  and  often  the  ophthalmic  divisions  are  also  usually  affected  in  cases 
requiring  to  be  approached  from  the  inside  of  the  skull. 


6o 


APPLIED   ANATOMY. 


Excision  of  the  Lingual  and  Inferior  Dental  Nerves. — Neuralgia  in- 
volving' the  face  below  the  line  of  the  mouth,  the  lower  teeth,  and  side  of  the  tongue 
requires  the  removal  of  the  inferior  dental  and  lingual  nerves.  To  do  this,  a  curved 
incision  following  the  lower  edge  of  the  mandible  is  made.  It  ends  anteriorly  in 
front  of  the  mandibular  foramen,  and  posteriorly  it  stops  a  centimetre  below  the  ear  to 
avoid  wounding  the  facial  nerve.  The  masseter  muscle  is  raised  from  the  bone,  and, 
with  the  parotid  gland,  is  drawn  up.  The  ramus  of  the  jaw  is  trephined  in  its  middle, 
rather  high  up  toward  the  coronoid  notch.  The  outer  table  of  bone  is  then  to  be 
chiselled  off,  from  the  trephine  opening  as  far  down  as  the  mental  foramen.  A 
delicate,  curved,  haemostatic  forceps  is  then  made  to  grasp  both  nerves  through  the 


Lingual  nerve 

Internal  pterygoid  muscle 

Mandibular  nerve 


Fig.  6S. — Excision  of  the  lingual  and  mandibular  (inferior  dental)  nerves. 

trephine  opening,  and  on  rotating  very  slowly  the  nerves  are  wound  around  the  for- 
ceps and  are  gradually  torn  loose  from  the  base  of  the  skull  above  to  their  ultimate 
branches  below  (see  Fig.  68). 

Operations  on  the  Gasserian  Ganglion. — The  Gasserian  ganglion  lies  in 
its  capsule,  formed  by  a  splitting  of  the  dura,  on  the  anterior  surface  of  the  apex  of 
the  petrous  portion  of  the  temporal  bone  and  on  the  root  of  the  greater  wing  of  the 
sphenoid.  From  its  posterior  extremity,  which  rests  on  the  ridge  separating  the 
anterior  and  posterior  surfaces  of  the  petrous  portion  of  the  temporal  bone,  to  the 
foramen  rotundum  anteriorly  is  2. 5  to  3  cm.  (i  to  i  ^  in.).  The  foramen  ovale,  which 
transmits  the  third  or  mandibular  branch  is  midway  between  these  two  points,  and 
corresponds  on  the  outside  of  the  skull  to  the  eminentia  articularis  or  root  of  the 
zygoma.  Therefore,  in  removing  the  ganglion  one  works  not  only  inward  but  also 
backward.  Rose  first  operated  on  the  ganglion  from  below.  He  removed  the 
zygoma  and  coronoid  process,  Hgated  the  internal  maxillary  artery,  and  trephined 
the  skull  in  front  of  the  foramen  ovale.  This  operation  was  succeeded  by  that  of 
Hartley  and  Krause.  They  went  in  through  the  temporal  fossa.  A  large  horseshoe- 
shaped  flap,  with  its  base  above  the  zygoma,  was  cut  and  deepened  with  chisels 
through  the  bone  to  the  dura.  This  was  elevated  by  breaking  across  its  base,  and  turn- 
ing it  down.  The  dura  was  then  lifted  from  the  base  of  the  skull,  and  the  maxillary 
and  mandibular  nerves  recognized  as  they  passed  into  the  round  and  oval  foramina. 
The  capsule  having  been  incised,  these  were  seized  with  forceps,  and  as  much  of  the 
ganglion  as  possible  torn  away. 

Other  surgeons,  like  Doyen,  Quenu,  Poirier,  and  Gushing,  have  combined  these 
pterygoid  and  temporal  routes.      The  bone  flap,  as  made  by  Hartley  and  Krause. 


THE   FACE. 


61 


embraced  the  region  of  the  pterion  or  junction  of  the  coronal  with  the  temporo- 
sphenoidal  sutures.  As  the  bone  was  lifted  from  the  dura  at  this  point  the  middle 
meningeal  artery  was  torn  and  troublesome  bleeding  ensued.  Also  the  point  of  its 
breaking  was  too  uncertain.  Sometimes  it  broke  too  high  up,  sometimes  too  low 
down  involving  the  base.  It  was  also  found  unnecessary  to  replace  the  bone  as 
the  cavity  left  was  filled  up  with  fibrous  tissue.  For  this  reason  Tiffany,  of  Baltimore, 
advocated  the  making  of  an  opening  in  the  skull  above  the  zygoma  with  a  trephine 
or  gouge  and  mallet,  and  enlarging  it  with  the  rongeur  forceps;  the  bone  was  not 
replaced.      This  is  the  procedure  now  used. 

The  operators  who  used  the  pterygoid  route,  by  displacing  the  zygoma  down- 
ward, were  enabled  to  approach  the  ganglion  from  below  instead  of  from  above, 
therefore,  a  high  temporal  section  of  the  bone  was  unnecessary  and  it  has  been 
abandoned;   the  bone  section   keeping  below  the   pterion   and   not  wounding    the 


N.ophthal- 
Gansjlion  semilunare     micus       N.  niaxillaris 


A.  meningea  media 


N.  iiiaiidibularis 


M.  pterygoideiis 
extenius, upper  head 

M.  pterygoideus 
externus,  lower  head 


M.  pterygoideus  interims 

N.  alveolaris  inferior 
(inferior  dental) 

N.  lingualis, 


N.  buccinatorius 


Fig.  69.— The  upper  portion  of  the  illustration  shows  the  operation  of  removal  of  the  Gasserian  ganglion  (ganglion 
semilunare).    The  lower  portion  shows  the  pterygoid  muscles. 


middle  meningeal  artery  thus  avoids  hemorrhage  from  that  locality.  Gushing 
(Journ.  Am.  Med.  Assoc,  April  28,  1900)  showed  that  the  extensive  removal  of  bone 
on  the  base  of  the  skull  was  unnecessary,  and  that  a  displacement  of  the  zygoma 
and  temporal  muscle  downward,  and  removal  of  the  bone  down  to  and  including 
part  of  the  infratemporal  crest  gave  sufficient  access.  Murphy  found  it  unnecessary 
to  resect  the  zygoma,  and  this  has  been  our  experience. 

One  of  the  main  difificulties  has  been  the  question  of  bleeding.  It  has  caused 
death  and  not  infrequently  has  necessitated  the  packing  of  the  wound  and  the 
deferring  of  the  completion  of  the  operation  for  two  or  more  days.  This  bleeding 
came  from  the  soft  parts,  the  bone,  the  middle  meningeal  artery,  the  veins  running 
from  the  dura  mater  to  the  bone,  the  cavernous  sinus,  and  the  blood-vessels  to  the 
ganglion  itself.  These  as  given  by  Gushing  are  a  branch  from  the  middle  meningeal 
soon  after  its  entrance  to  the  skull,  a  small  branch  from  the  carotid,  a  small  branch 
from  the  ophthalmic,  the  small  meningeal  through  the  foramen  ovale,  and  occasion- 
ally one  through  the  foramen  rotundum.  He  calls  attention  to  the  septa  in  the 
cavernous  sinus  as  rendering  wounds  to  it  less  serious  than  they  otherwise  would  be. 
If  the  skin  incision  is  cast  too  far  back,  the  temporal  artery  may  be  cut  in  front  of  the 
ear.  Its  position  can  be  determined  by  its  pulsation.  It  or  its  branches  are  divided 
in  the  upper  portion  of  the  incision  and  bleeding  is  very  free.  Division  of  the 
temporal  muscle  is  followed  by  hemorrhage  from  the  deep  temporal.  The  bleeding 
from  the  bone  is  usually  not  troublesome,  but  the  general  oozing  from  the  veins  of 


62 


APPLIED    ANATOMY. 


the  dura  mater  as  it  is  detached  from  the  bone  is  sometimes  free.  If  an  osteoplastic 
(bone  and  skin)  flap  is  raised,  the  middle  meningeal  will  be  torn  at  the  pterion. 
This  is  a  large  vessel  and  bleeds  freely.  It  may  also  be  torn,  while  isolating  the 
mandibular  division  of  the  nerve,  at  the  foramen  spinosum.  This  foramen  is  usually 
a  couple  of  millimetres  posterior  and  to  the  outer  side  of  the  foramen  ovale  and 
generally  the  nerve  can  be  isolated  without  injuring  the  artery.  In  some  cases,  how- 
ever, the  artery  lies  so  close  to  the  nerve  that  it  is  almost  certain  to  be  torn.  The 
posterior  portion  of  the  ganglion  lies  on  the  carotid  artery  in  the  middle  lacerated 
foramen,  of  course  separated  by  a  layer  of  dura  mater.  Care  should,  therefore,  be 
taken  not  to  injure  the  carotid  artery.  The  cavernous  sinus  has  often  been  injured. 
This  occurs  principally  in  those  cases  in  which  it  is  attempted  to  excise  the 
ophthalmic  division.  It  is  to  be  avoided  by  working  from  behind  forward  instead  of 
attempting  to  attack  it  laterally.      Bleeding  from  the  middle  meningeal  artery  can  be 


ophthalmic- 


Maxillary 


P-A  ^I-«d'bul 


Maxillarj-  _ 
Mandibular  ^A 

ical  plexus 


Fig.  70. — Diagrams  showing  distribution  of  cutaneous  branches  of  trigeminal  and  cervical  spinal  nerves  (Piersol). 

avoided  by  biting  the  skull  away  with  the  rongeur  forceps  and  refraining  from 
detaching  the  dura  from  the  bone  where  the  artery  enters  it  (see  Fig.  23). 

Gushing  states  that  he  makes  an  opening  in  the  bone  only  3  cm.  in  diameter. 
Such  a  small  opening  is  used  when  the  zygoma  has  been  divided  and  pushed  down 
or  removed.  Fowler  and  others  have  resorted  to  a  preliminary  Hgation  of  the 
external  carotid  artery.  This,  while  obviating  to  a  great  extent  troublesome  hem- 
orrhage, cuts  of?  the  blood  supply  to  the  flap  and  sloughing  has  followed.  In 
order  to  overcome  this  objection,  the  writer  {Jojirn.  Am.  Med.  Assoc,  April  28, 
1900)  after  ligating  the  external  carotid  artery  above  its  posterior  auricular  branch 
made  a  temporal  skin  flap  with  its  base  up.  The  temporal  muscle  was  then  divided 
and  turned  down  and  the  bone  removed  with  the  trephine  and  rongeur.  Haemostasis 
was  perfect  and  no  ill  effects  followed  the  ligation. 

It  is  comparatively  easy  to  isolate  the  maxillary  and  mandibular  divisions  of  the 
nerve.  This  having  been  done,  the  capsule  of  the  ganglion  is  opened  by  a  cut 
joining  the  two.  A  blunt  dissector  is  then  introduced  and  the  upper  layer  of  the 
dura,  less  adherent  than  the  lower,  is  raised  from  the  ganglion.  The  blunt  dissector 
is  then  worked  beneath  the  ganglion  beginning  between  the  maxillary  and  mandib- 
ular divisions  and  it  is  loosened  from  behind  forwards.  The  sixth  nerve  is  in  such 
close  relation  to  the  ophthalmic  that  a  temporary  paralysis  of  it  usually  follows, 
causing  internal  squint.  Anaesthesia  of  the  whole  side  of  the  face  from  just  in  front 
of  the  ear  to  the  median  line  follows  complete  removal.  Frazier  and  Spiller  have 
divided  the  root  posterior  to  the  ganglion  instead  of  removing  the  ganglion  itself 
(^Joiirn.  Am.  Med.  Assoc.  ^  Oct.  i,  1904,  p.  943). 


THE   FACE. 


63 


Area  of  Distribution  of  the  Fifth  Nerve, — When  the  ophthahiiic  division 
is  affected  the  pain  in  neuralgia  is  over  the  brow  and  up  toward  the  vertex  of  the 
skull;  it  also  involves  the  eye.  The  points  of  exit  of  the  supra-orbital  branch  at 
the  supra-orbital  foramen  and  of  the  nasal  branch  toward  the  lower  portion  of  the 
nose  are  tender  to  pressure. 

When  the  maxillary  division  is  affected,  there  is  pain  in  the  cheek  and  ala  of 
the  nose.  The  tender  points  are  the  exit  of  the  infra-orbital  nerve  at  and  below 
the  infra-orbital  foramen,  at  the  exit  of  the  malar  branch  on  the  malar  bone,  and 
tne  upper  gums  and  hard  palate. 

When  the  mandibular  division  is  affected  the  pain  involves  the  lower  jaw  and 
the  side  of  the  head  nearly  to  the  top  (auriculotemporal  branch).  The  lower  gums 
and  tongue  are  also  painful.  Pain  on  pressure  is  felt  over  the  mental  foramen  and  in 
the  course  of  the  auriculotemporal  nerve  in  front  of  and  above  the  ear. 


THE   LOWER   JAW. 

The  mmidible  or  mferior  maxilla  is  subject  to  fractures,  dislocation,  and  tumors. 
In  its  composition  it  is  very  dense,  so  that  in  dividing  it  a  groove  should  be  cut 
with  a  saw  before   the   use   of   the   bone-cutting   forceps   is   attempted,   otherwise 


Fig.  71. — Lower  jaw  of  child  and  adult,  showing  the  mental  foramen. 

splintering  of  the  bone  will  ensue.  It  is  the  last  bone  to  decay.  Its  horseshoe 
shape  and  exposed  position  render  it  unusually  liable  to  fracture.  The  strongest 
portion  is  what  one  would  expect  to  be  the  weakest,  viz.,  the  symphysis.  Its 
weakest  part  (or  rather  the  part  where  it  is  most  often  broken)  is  the  region  of  the 
mental  foramen.  The  bone  is  weakened  at  this  point  not  only  by  the  foramen 
but  also  by  the  deep  socket  of  the  canine  tooth. 

The  position  of  the  mental  foramen,  normally  between  the  two  bicuspids 
(beneath  the  second  in  the  negro — Humphry),  varies  in  its  vertical  location  between 
the  alveolar  border  and  lower  edge  of  the  body,  according  to  age.  In  infancy  it  is 
low  down,  in  young  adults  it  is  midway,  and  in  old  people  it  is  high  up. 

The  body  of  the  jaw  is  composed  of  two  parts,  one  above  and  one  below  the 
external  oblique  line,  which  runs  from  the  base  of  the  anterior  border  of  the 
coronoid  process  downward  and  forward  to  end  at  the  mental  tubercle,  to  one  side 
of  the  symphysis.  The  part  above  this  oblique  line  is  the  alveolar  and  the  part 
below  is  the  basal  portion  of  the  body. 

The  mental  foramen  opens  on  the  oblique  line  separating  the  alveolar  and  basal 
portions.  In  early  adult  life  the  two  portions,  basal  and  alveolar,  are  about  even  in 
size,  so  that  the  foramen  is  below  the  middle  of  the  jaw.  As  the  teeth  are  lost 
the  alveolar  process  atrophies ;  this  naturally  leaves  the  basal  portion  with  the  mental 


64 


APPLIED    ANATOMY. 


foramen  on  or  near  its  upper  surface;  therefore,  in  operating  for  neuralgia  in  the 
aged,  if  it  is  desired  to  attack  the  mandibular  nerve  in  its  canal,  it  should  be  searched 
for  near  the  upper  border  of  the  bone. 

In  infancy  the  teeth,  not  having  erupted,  are  contained  in  the  jaw,  the  alveolar 
portion  is,  therefore,  large.  The  basal  portion,  on  the  contrary,  is  quite  small,  serv- 
ing merely  as  a  narrow  shelf  on  which  the  unerupted  teeth  lie.  As  the  mandibular 
nerve  runs  beneath  the  teeth,  the  mental  foramen  is  of  necessity  comparatively  low. 
At  birth  the  condyle  is  about  level  with  the  upper  portion  of  the  symphysis,  and  the 
body  forms  with  the  ramus  an  angle  of  175  degrees.  At  the  end  of  the  fourth  year 
the  angle  has  decreased  to  about  140  degrees.  By  adult  age  the  angle  has  decreased 
to  about  115  degrees,  and  as  the  teeth  are  lost  the  angle  gradually  increases  until  it 
again  reaches  140  degrees. 

Temporomandibular  Articulation. — A  knowledge  of  the  movements  of  the 
jaw  is  essential  to  a  proper  understanding  of  the  fractures  and  dislocations  to  which 
it  is  subject. 


Temj)oralis 


Discus  articularis 


2ri_ Processus  condyloideus 


Pterygoideus  externus 


/ 


Fig.  72. — The  temporomandibular  articulation. 


The  mandible  articulates  with  the  glenoid  fossa  and  its  anterior  edge  or  emi- 
nentia  articularis  of  the  temporal  bone.  Interposed  between  the  condyle  below  and 
the  bone  above,   is  an  interarticular  cartilage.      This  divides    the    articulation  into 

two  portions,  an  upper  and  a  lower.  The  ligaments 
are  a  capsular,  strengthened  by  an  external  lateral 
(temporomandibular)  and  an  internal  lateral.  The 
capsular  ligament  is  weakest  anteriorly  and  strongest 
on  the  outer  side.  The  thickening  of  the  capsule 
on  its  outer  side  forms  the  external  lateral  or  tem- 
poromandibular ligament.  The  sphenomandibular 
or  internal  lateral  ligament  is  practically  distinct 
from  the  articulation.  It  runs  from  the  alar  spine 
on  the  sphenoid  above  to  the  mandibular  spine  or 
lingula,  just  posterior  to  the  mandibular  foramen 
below.  Between  it  and  the  neck  of  the  bone  run 
the  internal  maxillary  artery  and  vein.  When  the 
condyle  glides  forward  it  puts  the  posterior  portion 
of  the  capsule  on  the  stretch,  and  if  the  jaw  is  dislocated  this  part  of  the  capsule  is 
torn.  The  interarticular  cartilage  is  more  intimately  connected  with  the  lower  por- 
tion of  the  articulation.  The  same  muscle  that  inserts  into  the  neck  of  the  jaw  (the 
external  pterygoid)  likewise  inserts  into  the  cartilage ;  therefore,  the  two  move 
together,  so  that  when  the  condyle  goes  forward  the  cartilage  goes  forward  and  rides 
on  the  eminentia  articularis. 


Fig.  73. — External  lateral  ligament  of  the 
lower  jaw. 


THE    FACE. 


65 


Fig.  74- 


Illustrating  up-and-down  or  pure  hinge  motion  01 
the  mandible. 


Movements  of  the  Jaw. — The  jaw  has  four  distinct  movements.  It  can  be 
moved  directly  forward  or  backward;  up  and  down,  a  pure  hinge  motion;  a  rotary- 
movement  on  a  vertical  axis  through  one  of  the  condyles;  and  rotation  on  a  trans- 
verse axis  passing  from  side  to  side 
through  the  mandibular  or  inferior 
dental  foramina.  The  muscles  of  mas- 
tication are  the  temporal,  massder, 
and  ptoygoids  ;  these  are  sujiplied  by 
the  motor  branch  of  the  fifth  nerve. 
To  these  we  may  add  the  buccinator, 
which  is  supplied  by  the  seventh  nerve, 
and  the  depressors  of  the  jaw, — the 
digastric,  geniohyoid,  geniohyoglos- 
sus,  mylohyoid,  and  platysma.  The 
posterior  belly  of  the  digastric  receives 
its  nerve  supply  from  the  facial ;  its 
anterior  belly  from  the  mylohyoid 
branch  of  the  inferior  dental  from  the 
fifth.  The  mylohyoid  is  supplied  by 
the  mylohyoid  branch  of  the  inferior 
dental.  The  geniohyoid  and  genio- 
hyoglossus  are  supplied  by  the  hypo- 
glossal nerve.  The  platysma  is  sup- 
plied by  the  inframandibular  branch 
of  the  facial  nerve.  The  upward  move- 
ment is  produced  mainly  by  the  mas- 
seter  and  temporal  muscles.  It  is  the 
principal  movement  in  carnivorous 
animals  ;  therefore,  these  muscles  in 

them  are  well  developed,  and  the  joint  is  a  pure  hinge  joint.  The  internal  pterygoid 
and  buccinator  likewise  aid  in  closing  the  mouth  ;  the  depressors  already  mentioned 
open  it.     The  lateral  or  rotary  movement  around  a  vertical  axis  passing  through  one 

condyle  is  used  in  chewing  ;  therefore,  we 
find  the  muscles  most  concerned,  the  ptery- 
goids, best  developed  in  herbivorous  ani- 
mals, or  those  which  chew  the  cud.  The 
external  pterygoid  is  especially  efficient  in 
pulling  the  jaw  forward  ;  superficial  fibres 
of  the  masseter  help  in  this.  The  posterior 
fibres  of  the  temporal  muscle  pull  the  jaw 
back,  as  do  likewise  the  depressor  muscles 
of  the  jaw.  In  this  rotary  movement  one 
condyle  remains  back  in  its  socket  while  the 
other  is  brought  forward  on  the  eminentia 
articularis. 

The  up-and-down  movement  of  the 
jaws,  when  limited  in  extent,  is  a  pure  hinge 
movement  without  any  anteroposterior  dis- 
placement, and  takes  place  between  the  con- 
dyle and  the  interarticular  cartilage  (Fig. 
74).  The  anteroposterior  movement  is 
necessarily  accompanied  by  a  slight  descent 
of  the  jaw,  as  the  condyle  ghdes  from 
the  glenoid  cavity  (F"ig.  75)  onto  the  emi- 
nentia articularis.  It  goes  nearly,  but  not 
quite,  to  the  highest  point  of  the  articular 
If  the  jaws  are  kept  closed  during  this  anteroposterior  movement,  some 
of  the  teeth  of  the  upper  and  lower  jaws  will  still  be  in  contact,  the  number  varying 
in  different  individuals      '-^     «  • 

5 


Fig.  75. — Illustrating  direct  anteroposterior  move- 
ment of  the  mandible.  The  condyle  is  resting  on  the 
eminentia  articularis. 


eminence. 


The  last  molar  teeth  are  usually  higher  than  those  in  front, 


66  APPLIED    ANATOMY. 

so  that  as  they  glide  forward  the  last  lower  molars  strike  the  second  upper  ones. 
The  incisors  likewise  can  be  kept  in  contact  as  the  jaw  moves  backward  and  forward. 
It  is  this  movement  in  the  rodent  animals  which  keeps  their  edges  sharp.  In  chew- 
ing, the  jaw  is  depressed,  the  teeth  separated,  and  the  food  held  between  them  by  the 
tongue  and  buccinator  muscle.  The  teeth  are  then  approximated  by  the  lower  jaw 
closing  and  the  condyle  sliding  upward  and  backw^ard  from  the  eminentia  articularis 
into  the  glenoid  cavity,  carrying  with  it  the  articular  cartilage. 

The  hinge  motion  takes  place  between  the  condyle  and  the  interarticular  carti- 
lage. The  anteroposterior  motion  takes  place  between  the  interarticular  cartilage  and 
the  eminentia  articularis:  the  cartilage  is  carried  forward  with  the  mandible.  A  rotary 
movement  occurs  when,  in  chewing,  the  condyle  of  one  side  remains  in  the  glenoid 
cavity  while  that  of  the  other  rises  on  the  articular  eminence.  The  radius  of  rotation 
is  a  line  passing  from  one  condyle  to  the  other.  In  widely  opening  the  mouth,  as 
in  yawning,  the  condyles  are  tilted  forward  while  the  angles  of  the  mandible  are 


Temporal  muscle 


External  lateral  ligament 


Internal  pterygoid  muscle 


Masseter  muscle 


Fig.  76. — Dislocation  of  the  lower  jaw ;  the  zygoma  and  part  of  the  masseter  muscle  have  been  cut  away. 

carried  somewhat  backward.  As  the  axis  of  this  motion  passes  from  side  to  side 
through  the  mandibular  foramina,  this  portion  of  the  bone  moves  but  little,  and  the 
inferior  dental  vessels  and  nerve  are  not  put  on  the  stretch. 

Dislocation  of  the  Lower  Jaw. — The  forward  dislocation  is  practically  the 
only  one  to  which  the  jaw  is  subject.  Dislocations  in  other  directions  are  apt  to  be 
accompanied  by  fractures.  An  understanding  of  the  mechanism  of  the  production 
and  reduction  of  this  dislocation  requires  a  knowledge  of  the  movements  of  the  jaw, 
and  the  influences  which  the  ligaments  and  muscles  exert  in  limiting  them.  The 
normal  movements  of  the  jaw  have  already  been  discussed. 

The  ligaments  which  limit  the  movements  of  the  jaw  are  those  forming  the  cap- 
<sular  Hs;ament.  This  is  made  up  of  four  parts:  anterior,  posterior,  internal  lateral, 
and  external  lateral.  The  anterior  is  very  weak,  hence  pus  in  the  joint  is  most  apt 
to  make  its  exit  forwards.  It  is  readily  ruptured  in  dislocations.  The  posterior 
ligament,  though  stronger,  may  also  be  torn.  The  two  lateral  ligaments,  the  outer 
being  the  stronger,  become  tense  when  the  condyle  slips  forward  on  the  articular 
eminence.  In  dislocation  they  remain  attached  to  the  mandible  and  are  not  rup- 
tured (see  Fig.  76). 


THE    FACE. 


67 


Dislocation  occurs  when  the  mouth  has  been  widely  opened  and  the  condyles 
are  forward  on  the  articular  eminences.  Some  sudden  jar  accompanied  by  contrac- 
tion mainly  of  the  external  pterygoid  muscle  causes  the  condyle  to  slip  forward  just 
in  front  of  the  articular  eminences.  The  pterygoid  muscles  and  the  superficial  fibres 
of  the  masseter  muscles  aid  in  producing  the  luxation.  As  the  condyle  leaves 
the  articulation  to  jump  forward,  it  will  be  noted  that  it  does  so  by  an  extensive 
movement,  which  is  one  of  rotation  on  a  transverse  axis  passing  across  in  the 
region  of  the  mandibular  foramina.  The  condyle  once  out  of  its  socket  is  kept 
out  by  the  contraction  of  the  temporal,  masseter,  and  internal  and  external  pterygoid 
muscles. 

Reduction  of  Dislocation  of  the  Lower  Jaw. — In  reducing  the  dislocation, 
the  condyles  must  be  depressed  and  pushed  back.  This  can  be  done  by  one  of  two 
ways:  viz.,  the  thumbs  of  the  surgeon,  being  protected  by  wrapping  with  a  towel  or 
bandage,  are  placed  on  the  last  molar  teeth,  and  the  jaw  firmly  grasped  with  the 
fingers  beneath  it.  The  back  part  of  the  jaw  is  then  pressed  downward,  the  chin 
tilted  upward,  and  the  condyles  slid  back  into  place. 


Small  fragment  into  which 
was  inserted  the  g^eiiiohyoid 
and  geniohyoglosbus  muscles 

Fig.  77. — Fracture  of  the  mandihle  through  the  symphysis  (author's  sketch). 


The  other  method  is  to  place  two  corks,  one  on  each  side,  or  a  piece  of  wood, 
transversely,  between  the  last  molar  teeth,  then  raise  the  chin  and  push  it  backward. 

The  undetached  lateral  ligaments  are  put  on  the  stretch  when  the  condyle  is 
luxated  forward.  Lewis  A.  Stimson  believes  that  in  attempting  reduction  the  jaw 
should  first  be  opened  wider  to  relax  these  and  then  pushed  back,  but  we  are 
not  prepared  to  admit  that  so  doing  does  relax  these  ligaments.  He  has,  however, 
shown  that  the  interarticular  cartilage  may  become  displaced  and,  by  filling  up  the 
articular  cavity,  prevent  a  proper  reduction.  In  rare  instances  the  catching  of  the 
coronoid  process  beneath  the  malar  bone  may  hinder  replacement. 

Fractures  of  the  Lower  Jaw  f Mandible). — Fractures  of  the  lower  jaw 
almost  never  occur  through  the  symphysis;  this  is  on  account  of  its  being  the  thickest 
and  strongest  part  of  the  bone.  When  a  fracture  of  the  anterior  portion  of  the  jaw 
detaches  a  median  piece  a  most  dangerous  condition  is  produced.  The  piece,  if 
sufficiently  loosened  by  the  injury,  is  drawn  back  into  the  throat,  carrying  the  tongue 
with  it  and  tending  to  suffocate  the  patient.  Such  a  case  is  recorded  by  A.  L. 
Peirson  (review  by  Geo.  W.  Norris,  Amer.  Jour.  Med.  Scietices,  1841,  N.  S.  vol.  i, 
p.  186).  A  man  was  run  over  by  a  wheel  which  passed  over  his  jaw,  fracturing  it 
on  each  side  and  forcing  the  piece  into  his  moiith.  The  piece  was  drawn  backward 
and  nearly  caused  death  from  suffocation. 


68 


APPLIED    ANATOMY. 


In  the  Annals  of  Surgery  (vol.  xix,  1894,  p.  653)  is  recorded  a  case  of  the 
author's  in  which  a  man,  while  drunk,  fell  and  struck  his  chin  on  the  curbstone.  A 
fracture  was  produced  through  the  symphysis  above  and  branching  to  each  side  of 
the  genial  tubercle  below.  This  small  median  piece  was  drawn  back  into  the  throat 
nearly  to  the  hyoid  bone,  and  suffocative  symptoms  were  marked.     These  disap- 


Geniohyoid  muscle         Geniohyoglossus  muscle 
Fig.  78. — Anteroposterior  section  of  the  tongue  and  floor  of  the  mouth,  near  the  midline. 

peared  when  the  detached  piece  was  drawn  forward  and  wired  in  place.  The  piece 
was  drawn  backward  by  the  geniohyoid  and  geniohyoglossus  muscles.  The  digas- 
trics may  also  have  aided  in  depressing  the  fragment  (Figs.  77  and  78). 

The  most  usual  site  of  fracture  is  in  the  neighborhood  of  the  mental  foramen. 
This  is  located  just  below  the  second  premolar  tooth  (sometimes  between  the  first 
and  second).      This  foramen  and  the  large  socket  for    the   canine    tooth   farther 


Temporal  muscle 


Masseter  muscle 


Buccinator  muscle 


A 


Mylohyoid  muscle 

Digastric  muscle 

Fig. 79. — Fracture  of  the  lower  jaw  in  the  region  of  the  mental  foramen,  showing  the  line  of  fracture  and  the  influ- 
ence of  the  muscles  in  producing  displacement. 

forward  weaken  the  bone  somewhat  in  this  region.  The  jaw  is  strengthened  behind 
the  mental  foramen  by  the  commencement  of  the  anterior  portion  of  the  ramus  and 
by  an  increase  in  the  size  of  the  mylohyoid  ridge  on  the  inner  surface.  The  jaw  is 
also  protected  by  the  thick  masseter  muscle  and  fracture  is  most  liable  to  occur  just 
in  front  of  it.      This  constitutes  the  typical  fracture  of  the  lower  jaw  (Fig.  79). 


THE    FACE. 


69 


Fig.  80. — Fracture  of  the  lower  jaw,  showing 
the  Hne  of  fracture  proceeding  downward  and 
backward,  favoring  displacement. 


Displacement. — The  displacement  of  the  fragments  will  depend  on  the  line  of 
fracture;  and  the  line  of  fracture  may  be  determined  by  the  direction  and  character  of 
the  fracturing  force.  The  line  of  fracture  is  oblique.  It  may  be  oblique  from  above 
down  or  from  without  in.  An  examination  of  the  muscles  attached  to  the  mandible 
will  show  that  the  elevators  of  the  jaw  are  attached  to  it  posteriorly  and  its  depres- 
sors anteriorly.  On  this  account,  when  the  fracture  runs  obliquely  down  and 
forward  there  is  little  or  no  displacement,  because  the  depressors  and  elevators  tend  to 
press  the  fragments  together.  When  the  fracture 
runs  downward  and  backward  (see  Fig.  80),  the 
depressors  and  elevators  tend  to  separate  the 
fragments.  The  depression  of  the  anterior  frag- 
ment is  particularly  marked  when  the  fracture  is 
double,  involving  both  sides  of  the  jaw.  The 
muscles  which  tend  to  depress  the  anterior  frag- 
ment are  the  geniohyoglossus,  geniohyoid,  mylo- 
hyoid (anterior  portion),  digastric,  and  platysma. 
The  muscles  which  elevate  the  posterior  frag- 
ment are  the  temporal,  masseter,  buccinator,  and 
internal  pterygoid. 

The  displacement  may  not  only  be  up  and 
down,  but  may  also  be  lateral.  The  line  of  frac- 
ture may  run  from  the  outside  either  inward 
and  backward  or  inward  and  forward.  The  jaw  is  held  in  place  by  its  own  rigidity 
when  intact ;  when  broken,  the  smaller  fragment  is  liable  to  be  pulled  inward  by  the 
muscles  passing  from  it  toward  the  median  line.  These  muscles  are  the  internal 
pterygoid  and  the  mylohyoid.  The  influence  of  the  former  is  more  marked  than  of 
the  latter,  because  the  fracture  frequently  divides  the  mylohyoid,  leaving  a  part  of 
it  attached  to  each  fragment.      When  the  fracture  passes  from  without  inward  and 

backward,  then  there  will  be  little  or  no 
displacement,  because  the  internal  ptery- 
goid and  mylohyoid  draw  the  fragments 
together.  (See  Fig.  81.)  When  the 
line  of  fracture  is  from  without  inward 
and  forward,  the  internal  pterygoid  of 
the  injured  side  and  the  mylohyoid  draw 
the  posterior  fragment  inward,  while  the 
internal  pterygoid  of  the  opposite  side 
draws  the  anterior  fragment  outward 
(Fig.  82). 

From  a  consideration  of  the  forego- 
ing facts,  we  see  that  when  there  is  dis- 
placement it  is  because  the  fracture  runs 
from  above  downward  and  backward, 
and  from  without  inward  and  forward. 
The  anterior  fragment  is  displaced  down- 
ward and  the  posterior  fragment  is  dis- 
placed inward. 

Fractures  through  the  region  of  the 
molar  teeth  are  not  particularly  uncom- 
mon, and  this  is  likewise  the  case  with  fractures  obliquely  downward  and  outward 
through  the  angle  of  the  jaw.  In  these  injuries  the  firm  attachment  of  the  masseter 
on  the  external  surface  of  the  jaw  and  the  internal  pterygoid  on  its  inner  prevent 
displacement. 

Fractures  of  the  coronoid  process  are  exceedingly  rare.  In  them  displacement 
is  prevented  by  the  attachment  of  the  temporal  muscle,  which  passes  much  farther 
down  on  the  inside  than  on  the  outside. 

Fractures  of  the  neck  of  the  jaw  are  particularly  serious.  Inserted  into  the 
condyle  and  neck  of  the  jaw  is  the  external  pterygoid  muscle.  When  a  fracture  of  the 
neck  occurs,  this  muscle  pulls  the  upper  fragment  anteriorly  and  tends  to  tilt  its 


Fig.  81. — Fracture  of  the  jaw,  showing  absence  of  dis- 
placement when  the  line  of  fracture  runs  from  the  inside 
forward  and  outward. 


70 


APPLIED  ANATOMY. 


upper  end    inward.      This   displacement    is    so   marked    that  an   excessive   amount 
of   callus  is   thrown   out  and    ankylosis    may   result.       This   so    seriously  interferes 


FiG  82. — Fracture  of  the  jaw,  showing  the  action  of  the  internal  pterygoid  and  mylohyoid  muscles  in  producing 
displacement  when  the  line  of  fractuie  runs  from  the  outside  forward  and  inward. 

with  the  use  of  the  jaws  as  to  justify  an  operation  to  remove  or  replace  the  upper 
fragment  in  proper  position.  The  injury  is  liable  to  be  overlooked  in  children,  and 
as  they  grow  up  the  deformity  shown  in  Fig.  83  develops. 


Fig.  83. — Deformity  of  the  face  following  ankylosis  due  to  fracture  of  the  neck  of  the  lower  jaw  in  infancy  (from  an 

original  sketch). 

Treatment. — The  lower  jaw  is  held  up  in  place  by  a  bandage,  and  the  upper 
teeth  act  as  a  splint.  Sometimes  the  teeth  or  fragments  are  wired  in  position,  or  an 
interdental  splint  of  gutta  percha  or  other  material  is  used. 


THE    FACE. 


n 


Excision  of  the  Condyle  of  the  Jaw. — The  condyle  can  be  removed 
through  an  incision  3  cm.  long,  running  from  in  front  of  the  ear  along  the  lower  border 
of  the  zygoma.  The  temporal  artery  runs  a  centimetre  in  front  of  the  ear  with  the 
auriculotemporal  nerve  posterior  to  it.  By  care  in  recognizing  the  artery,  it  may  be 
saved  and  dragged  posteriorly.  The  soft  parts  on  the  lower  side  of  the  wound  with 
the  parotid  gland  and  facial  nerve  are  pushed  downward.  The  condyle  can  then 
be  dug  out,  care  being  taken  not  to  go  beyond  the  bone  and  wound  the  internal 
maxillary  artery. 

Excision  of  the  Mandible. — In  removing  one-half  of  the  mandible,  the 
incision  is  made  from  the  symphysis  along  the  lower  border  of  the  jaw  to  the  angle 
and  thence  upward  as  high  as  the  lobe  of  the  ear.  If  it  is  desired  to  take  extra 
precautions,  the  last  centimetre  of  this  incision,  from  the  lobule  of  the  ear  down,  may 
be  carried  through  the  skin  only.  This  will  prevent  wounding  to  any  great  extent 
the  parotid  gland  tissue,  the  parotid  duct,  and  positively  avoid  injuring  the  facial 
nerve.  The  incision,  however,  is  rather  far  back  to  wound  any  large  branch  of  the  duct, 
and  is  too  low  down  to  wound  the  facial  nerve.  If  it  is  desired  to  carry  the  incision 
higher  than  the  lobule  of  the  ear,  it  should  go  through  the  skin  only.  The  facial 
artery  and  vein  will  be  cut  just  in  front  of  the  masseter  muscle.      The  soft  parts. 


Fig.  84. — Excision  of  the  condyle  of  the  lower  jaw. 


including  the  masseter  muscle,  are  raised  from  the  outer  surface.  In  dividing  the 
bone  anteriorly,  it  should  be  done  .5  cm.  outside  the  median  line.  This  will  be 
about  through  the  socket  of  the  second  incisor.  The  object  of  this  is  to  retain  the 
attachments  of  the  genioliyoid  and  geniohyoglossus  muscles  to  the  genial  tubercles, 
and  so  prevent  any  tendency  of  the  tongue  to  fall  back.  The  jaw  is  pulled  out  and 
separated  from  the  parts  beneath,  the  mylohyoid  muscle  being  made  tense.  Care 
should  be  taken  not  to  injure  the  submaxillary  gland,  which  lies  below  the  mylohyoid 
muscle,  and  the  sublingual  gland,  which  lies  above  it.  The  lingual  nerve  is  also  liable 
to  be  wounded  if  the  knife  or  elevator  is  not  kept  close  to  the  bone. 

As  the  detachment  proceeds  posteriorly,  in  loosening  the  internal  pterygoid  and 
the  superior  constrictor,  if  care  is  not  taken,  the  pharynx  may  be  wounded.  The 
bone  still  being  depressed  and  turned  outward,  the  temporal  muscle  is  to  be  loosened 
from  the  coronoid  process  or  else  the  process  is  detached  and  removed  later.  Access 
is  now  to  be  had  to  the  mandibular  foramen  at  the  mandibular  spine  or  spine  of  Spix. 
The  inferior  alveolar  artery  is  then  secured  and,  with  the  nerve  and  sphenomandibular 
ligament,  divided.  The  jaw  can  now  be  well  depressed  and  brought  inward.  The 
temporomaxillary  joint  is  to  be  opened  from  the  front,  having  first  cleared  off  the 
attachment  of  the  external  pterygoid  muscle.  There  is  great  danger  of  wounding 
the  internal  maxillary  artery  at  this  stage  of  the  operation.      It  lies  close  to  the  neck 


72 


APPLIED    ANATOMY. 


of  the  jaw,  and  it  is  to  avoid  bringing  it  too  close  to  the  bone  that  Jacobson  advises 
that  the  jaw  be  not  twisted  outward  when  disarticulation  is  being  performed. 

The  distance  between  the  coronoid  process  and  malar  bone  varies  in  different 
individuals.  The  process  may  be  displaced  by  the  tumor  and  thus  prevent  detachment 
of  the  temporal  muscle.  If  so,  the  process  is  divided  with  forceps  or  saw  and  removed 
after  the  rest  of  the  jaw  has  been  taken  away.      Injury  of  the  temporomaxillary  veins 


Tongue 


Geniohyoglossus  muscle 
Geniohyoid  muscle 
Mylohyoid  muscle 


Anterior  belly  of 
digastric  muscle 


Masseter  muscle 
Lingual  nerve 


Muscular  branches 
of  internal  maxil- 
lary artery 

Inferior  alveolar 
(dental )  nerve  and 
artery 
.Internal  pterygoid 
muscle 
Duct  of  submaxillary 
gland 
Facial  vein 


Facial  artery 
Sublingual  gland 
Fig.  85. — Excision  of  one-half  of  the  lower  jaw,  showing  the  structures  exposed. 

may  be  avoided  by  not  going  behind  the  posterior  edge  of  the  ramus,  as  is  also  the 
case  with  the  external  carotid  artery.  Access  to  the  joint  may  be  facilitated  by  drag- 
ging upward  the  parotid  gland,  which  carries  with  it  the  facial  nerve  and  parotid  duct. 


REGION   OF  THE   EYE. 

The  eyeball  rests  in  its  socket,  which  is  hollowed  out  of  the  soft  parts  contained 
in  the  bony  orbit.  It  is  covered  in  front  by  the  lids,  which,  as  they  slide  over  the 
eye,  are  lubricated  by  the  tears.  These  are  secreted  by  the  lachryynal  gland  at  the 
upper  outer  portion  of  the  orbit,  flow  over  the  eye,  and  are  drained  off  by  the  lach- 
rymal canals  and  sac  to  empty  into  the  nose  through  the  lachrymonasal  duct. 

The  Orbits. — The  orbits  are  large  four-sided  cavities,  pyramidal  in  shape. 
The  orbit  in  an  adult  male  is  about  4  cm.  in  diameter  from  side  to  side,  and  3.5  cm. 
from  above  downward.  The  depth  is  4. 5  cm.  It  is  thus  seen  that  the  orbit  is  wider 
than  it  is  high.  On  receding  into  the  orbit  from  its  bony  edge,  the  roof  arches 
upward  toward  the  brain  to  receive  the  lachrymal  gland,  thus  making  the  up-and- 
down  diameter  slightly  longer  than  the  transverse. 

The  rim  of  the  orbit  is  very  strong  and  not  readily  broken  by  injuries.  It  is 
formed  by  the  frontal  bone  above,  the  malar  bone  to  the  outside,  the  malar  and  supe- 
rior maxillary  below,  and  the  superior  maxillary  and  frontal  to  the  inside.  The 
inner  (medial)  walls  of  the  two  orbits  are  parallel,  running  distinctly  anteroposte- 
riorly.     The  outer  (lateral)  walls  diverge  at  an  angle  of  about  45°  from  the  inner  ones. 

The  outer  or  lateral  edge  of  the  orbit  is  nearly  or  quite  a  centimetre  and  a  half 
posterior  to  the  inner  or  medial  edge.  This  fact,  together  with  the  divergence  of  the 
outer  wall,  is  the  reason  that,  in  enucleation  of  the  eye,  it  is  always  tilted  toward  the 
nose,  and  the  scissors  introduced  and  the  nerve  cut  from  the  outer  side. 

The  oviter  wall  of  the  orbital  cavity  is  formed  mainlv  by  the  broad  flat  surface  of 
the  greater  wing  of  the  sphenoid  bone,  and  is  thick  and  strong.     The  other  three 


REGION    OF   THE    EYE. 


73 


walls,  on  the  contrary,  are  thin  and  weak.  The  thin  orbital  plate  of  the  frontal  bone 
above  is  frequently  fractured  in  puncture  wounds  by  foreign  bodies,  and  the  frontal 
lobe  of  the  brain  injured.      Two  such  instances  have  come  under  the  writer's  care; 


Supra-orbital  notch 

Lachr>'inal  groove 
Optic  foramen 


Sphenoidal  (superior 
orbital)  fissure 


Sphenomaxillary  (In- 
ferior orbital)  fissure 


Fig.  86.— The  bony  orbit. 


Infra-orbital  sulcus 


Infra-orbital  foramen 


in  the  first  case,  an  iron  hook  had  penetrated  and  caused  death  from  cerebritis  ;  in 
the  second,  the  wound  was  caused  by  a  carriage  pole.  The  patient  recovered, 
notwithstanding  a  considerable  loss  of  brain  tissue. 


Sphenoidal  sinus 


Inferior  orbital 
fissure 


Infra-orbital  sulcus 

Ethmoidal  cells 
—   Lachrjmal  canal 

Nasal  septum 


Fig.  87. — Transverse  section  of  the  orbital  and  nasal  cavities  viewed  from  above. 

To  the  medial  side  of  the  inner  wall  are  the  ethmoid  cells,  covered  by  the  thin 
lachrymal  bone  and  the  os  planum  of  the  ethmoid.  They  are  readily  perforated  by 
suppuration  from  within  those   cavities.     The  floor  is  chiefly  formed  by  the  thin 


74 


APPLIED    ANATOMY. 


orbital  plate  of  the  superior  maxilla.  In  operations  involving  the  floor  of  the 
orbit,  care  is  necessary  to  avoid  breaking  through  into  the  maxillary  sinus  (antrum) 
beneath. 

At  the  edge  of  the  junction  of  the  outer  and  lower  walls  lies  the  inferior  orbital 
(^sphe7iomaxillary)  fissure.  It  runs  forward  to  within  1.5  cm.  of  the  edge  of  the 
orbit  and  extends  back  to  the  apex  of  the  orbit,  where  it  unites  with  the  superior 
orbital  {^sphenoidal)  fissure,  which  lies  between  the  roof  and  outer  wall  and  extends 
forward  about  one-third  of  the  distance  to  the  edge  of  the  orbit.  The  optic  fiora men 
enters  the  apex  of  the  orbit  at  its  upper  and  inner  portion. 

At  the  lower  inner  edge  of  the  orbit  is  the  lachrymal  groove  for  the  lachrymo- 
nasal  duct,  leading  from  the  eye  to  the  inferior  meatus  of  the  nose.  At  the  junction  of 
the  middle  and  inner  thirds  of  the  upper  edge  is  the  supra-orbital  notch.  This  can 
be  felt  through  the  skin.  It  transmits  the  supra-orbital  artery  and  7ierve.  If  a 
complete  foramen  is  present  instead  of  a  notch,  its  location  cannot  be  so  readily 
determined. 

Contents  of  the  Orbit. — The  orbit  is  lined  with  a  periosteum,  and  contains 
the  eyeball,  the  muscles  which  move  it,   the  veins,  arteries,   and  nerves  which  go  to 


Superior  oblique  muscle 

Superior  orbitotarsal 

ligament 

Levator  palpebrse 

superior  muscle 

Superior  rectus  muscle 
Tarsal  cartilage 


Inferior  rectus  muscle 
Inferior  oblique  muscle 


Capsule  of  Tenon 


Inferior  orbito- 
tarsal ligament 


Fig.  88. — Sagittal  section  through  the  eye  and  orbit. 


it  together  with  some  which  traverse  the  orbit  to  go  to  the  face,  and  the  lachrymal 
gland.  These  structures  are  more  or  less  surrounded  with  a  fascia  which  is  continu- 
ous with  the  periosteum. 

Periosteum. — The  periosteum  of  the  orbit  is  not  tightly  attached  and  in  cases 
of  disease  can  readily  be  raised  from  the  bone  beneath.  Anteriorly,  it  is  continuous 
at  the  orbital  rim  with  the  periosteum  of  the  bones  of  the  face.  Posteriorly,  it  is  con- 
tinuous through  the  optic  foramen  and  sphenoidal  fissure  with  the  dura  mater. 
It  sends  prolongations  inward,  covering  all  the  separate  structures  in  the  orbit. 
From  the  edge  of  the  orbit  it  stretches  over  to  the  tarsal  cartilages,  forming  the 
superior  and  inferior  orbitotarsal  ligaments.  These  form  a  barrier  (called  the  sep- 
tum orbitale)  to  the  exit  of  pus  from  within  the  orbit,  and  for  that  reason  it  is  advised 
that  orbital  abscesses  should  be  opened  early.  The  lower  portion,  as  it  reaches 
the  lachrymal  groove,  splits  to  cover  the  lachrymal  sac.  Another  extension 
from  above  splits  to  enclose  the  lachrymal  gland,  which  is  seen  to  lie  comparatively 
loose  in  the  upper  outer  portion  of  the  orbit,  sustained  by  its  suspensory  ligament. 
It  then  sends  thin  fibrous  layers  which  cover  the  muscles,  arteries,  veins,  nerves,  fat 
pellicles,  and  finally  the  eyeball  posterior  to  the  insertion  of  the  muscles  and  optic 
nerve.      This  last  portion,  called  the  capsule  of  Tenon,  begins  as  far  forward  as  the 


REGION    OF   THE    EYE. 


75 


insertion  of  the  recti  muscles  on  their  under  (inner)  side,  passes  over  the  globe  poste- 
riorly, over  the  optic  nerve,  and  blends  with  the  layer  covering  the  deep  surface  of  the 
muscles.  It  is  joined  to  the  sclerotic  coat  of  the  eye  and  dural  sheath  of  the  nerve 
by  a  loose  net-work  of  delicate  fibrils.  This  forms  practically  a  space  lined  with 
endothelial  plates,  similar  to  the  subarachnoid  space  in  the  brain.  The  capsule  of 
Tenon  is  a  distinct,  well  marked  membrane,  and  the  eyeball  lies  loose  and  revolves 
freely  within  it.  It  is  this  space  into  which  the  strabismus  hook  is  put  when  it  is 
desired  to  cut  the  recti  muscles  for  squint.  Fibrous  prolongations  are  also  sent 
to  the  sides  of  the  orbit  from  the  internal  and  external  recti  muscles.  They  are 
the  check  ligaments;  and  one  from  the  inferior  rectus  forms  the  suspensory  ligament 
of  the  eye. 

Affections  of  the  Orbit. — The  orbit  is  often  invaded  by  tumors,  pus,  hemor- 
rhages, and  air  (producing  emphysema). 

Tu77ioi'S  may  either  originate  in  the  orbital  contents,  as  sarcomas  of  the  lach- 
rymal gland  or  eye,  or  they  may  come  from  surrounding  regions.  It  is  more  rare 
for  them  to  enter  through  the  natural  openings  of  the  orbit  than  it  is  for  them  to 
push  through  its  thin  walls.  Coming  through  natural  openings,  they  may  make 
their  entrance  :   (i)  from  the  brain  through  the  optic  foramen  or  sphenoidal  fissure  ; 

(2)  from  the  region  of  the  zygomatic  and  temporal  fossae  through  the  sphenomaxil- 
lary fissure ;   (3)  from  the  nasal  cavities 

(as  I  have  seen),  coming  up  the  lachry- 
monasal  canal. 

In  invading  the  orbit  through  its  walls 
they  may  come:  (i)  from  the  nasal  cavi- 
ties and  ethmoidal  cells,  pushing  through 
the  thin  internal  wall ;  (2)  from  the  frontal 
sinus,  appearing  at  the  upper  inner  angle; 

(3)  from  the  sphenoidal  cells  at  the  pos- 
terior portion  of  the  inner  wall ;  (4)  from 
the  brain  cavity  above,  breaking  through 
the  roof ;  (5)  from  the  maxillary  sinus 
below,  pushing  through  the  floor. 

Dermoids.  — In  the  foetus,  the  fronto- 
nasal process  comes  from  above  down- 
ward to  join  the  maxillary  processes  on 
each  side.  This  leaves  an  orbitonasal  cleft  to  form  the  orbit.  Owing  to  defects  in  the 
development  of  this  cleft,  dermoid  tumors  may  occur  in  its  course.  They  are  seen 
either  at  the  outer  or  inner  angle  of  the  eye.  They  are  more  common  at  the  outer 
angle  near  the  external  angular  process,  and  may  have  a  prolongation  to  the  dura 
mater.  They  also  occur  at  the  inner  angle  at  the  frontonasal  suture  (Fig.  89).  At 
this  point,  also,  meningoceles  are  liable  to  occur.  As  pointed  out  by  J.  Bland  Sutton 
the  question  of  diagnosis  is  of  importance,  as  an  attempt  to  remove  a  meningocele 
by  operation  is  apt  to  be  followed  by  death,  whereas  a  dermoid,  though  it  may  have 
a  fibrous  prolongation  to  the  dura  mater,  can  be  more  safely  removed. 

Orbital  Abscess. — Suppuration  may  either  originate  within  the  orbit  or  extend 
into  it  from  the  neighboring  tissues.  If  the  former  is  the  case,  it  may  occur  from 
caries  of  the  bones  of  the  orbit,  as  in  syphilis.  It  may  originate  from  erysipelas 
involving  the  orbit.  General  inflammation  and  suppuration  of  the  eye  may  break 
through  the  eye  and  spread  in  the  orbital  tissues  (panophthalmitis).  If  pus  enters 
the  orbit  from  the  outside,  it  is  usually  from  suppuration  and  caries  of  the  frontal 
sinus  and  ethmoidal  cells.  In  this  case,  the  swelling  shows  itself  at  the  upper 
portion  of  the  inner  angle  of  the  eye.  Pus  in  the  maxillary  sinus  is  most  apt  to 
discharge  into  the  nose,  and  not  break  through  the  roof  into  the  orbit  above. 
Pus  within  the  orbit  tends  to  push  the  eyeball  forward  and  even  distend  the  lids. 
As  the  orbitotarsal  ligament  runs  from  the  bony  edge  of  the  orbit  to  the  lids,  pus 
does  not  find  an  easy  exit.  The  abscess  should  be  opened  by  elevating  the  upper 
lid,  and  incising  the  conjunctiva  in  the  sulcus  between  the  globe  of  the  eye  and  the  lid. 
Pus  from  suppuration  of  the  lachrymal  sac  does  not  tend  to  invade  the  orbit  but 
works  its  way  forward  to  the  skin. 


Fig.  89. — Dermoid  of  orbit.  Boy,  15  years  of  age.  It 
extended  back  to  the  body  of  the  sphenoid  bone.  Case  of 
Dr.  Wm.  Zentmayer. 


76 


APPLIED    ANATOMY. 


Foreig?i  Bodies  i7i  the  Orbit. — Owing  to  the  considerable  space  which  exists 
between  the  eye  and  orbital  walls,  large  foreign  bodies  may  find  a  lodgment  there, 
often  producing  serious  symptoms  for  a  considerable  length  of  time.      The  tang  of 


Fig.  90. — Lines  of  the  skin  incision.    (Kronlein's  operation  for  obtaining  access  to  the  retrobulbar  region.) 


a  gun  barrel  has  been  so  found.     This  should  lead  one  to  search  for  foreign  bodies 
carefully  when  this  portion  of  the  orbital  contents  has  been  wounded. 


Periosteal  lining  of  orbit         Incision 


Fig.  91. — The  rim  of  the  orbit  has  been  divided  and  the  piece  of  the  bone  turned  outward  ;  an  incision  is  then  made 
through  the  periosteal  lining.    (Kronlein's  operation  for  obtaining  access  to  the  retrobulbar  region.) 


Emphysema. — In  cases  of  fracture  involving  the  inner  wall  and  opening  up  the 
nasal  cavities  or  sinuses  the  air,  particularly  in  blowing  the  nose,  may  be  forced  into 


Periosteal  lining 


Stump  of  rectus  externus  muscle 


Rectus  externus  cut  and  turned  back 


Bulb  of  eye 
Optic  nerve 


Fig. 92. — The  edges  of  the  incised  periosteum  have  been  separated  and  the  external  rectus  muscle  divided,  exposing 
the  space  posterior  to  the  bulb.    (Kronlein's  operation  for  obtaining  access  to  the  retrobulbar  region.) 

the  orbit,  distending  the  lids  and  producing  a  peculiar  crackling  sensation  when 
palpated.  No  treatment  directed  to  removal  of  the  air  is  necessary.  It  is  valuable 
as  a  diagnostic  sign  of  fracture  communicating  with  the  nasal  cavities. 


REGION    OF   THE    EYE. 


77 


Hemorrhage. — Hemorrhage  into  the  orbit  may  occur  either  as  the  resuh  of 
direct  traumatism  inxolving  the  contents,  or  from  fracture  of  the  base  of  the  skull 
through  the  orbital  plate.  The  blood  pushes  its  way  anteriorly  and  shows  itself 
under  the  conjunctiva  surrounding  the  cornea.  It  is  prevented  from  appearing 
on  the  lids  by  the  orbitotarsal  ligament.  A  subconjunctival  hemorrhage  alone  is  not 
sufficient  to  justify  a  diagnosis  of  fracture  of  the  base  of  the  skull,  although  it  is 
a  significant  confirmatory  symptom. 

Kronlein's  Operation. — In  order  to  gain  access  to  the  back  part  of  the  orbit 
to  remove  tumors,  Krbnlein  resects  the  outer  wall,  divides  the  periosteum  and 
external  rectus  muscle,  and  so  gains  access  to  the  retrobulbar  space.  The  various 
steps  of  the  operation  are  shown  in  Figs.  90,  91,  92. 

THE  EYEBALL  AND  OPTIC  NERVE. 

The  eyeball  has  three  main  coats,  viz. :  a  fibrous  outer  coat,  called  the  sclerotic; 
a  vascular  middle  coat,  the  choroid ;  and  a  nervous  inner  coat,  the  retina. 

Sclerotic  Coat. — The  sclerotic  coat  forms  a  firm  protective  covering  or  case 
for  the  delicate  retina  within.  It  is  continuous  posteriorly  with  the  fibrous  coat  or 
dura  of  the  optic  nerve,  which  is  a  continuation  of  the  dura  mater  of  the  brain.  At 
the  optic  foramen,  the  dura  mater  splits  into  two  layers;  the  outer  layer  forms  the 
periosteum,  while  the  inner  forms  the  dural  coat  of  the  optic  nerve.  This  nerve  also, 
like  the  brain,  has  an  arachnoid  and  a  pial  membrane.  The  sclerotic  coat  is  con- 
tinued forward  over  the  front  of  the  eye  as  the  cornea.  As  it  is  essentially  a  mem- 
brane intended  to  be  protective  in  its  function,  its  diseases  are  those  of  weakness: 
thus,  if  the  cornea  is  affected,  it  bulges  forward  and  is  called  an  anterior  staphyloma  ; 
if  the  posterior  part  is  affected,  the  sclera  is  stretched,  and  it  forms  a  posterior 
staphyloma. 

Anterior  staphyloma  may  occur  either  rapidly  as  a  small  local  protrusion,  resulting 
from  ulceration  of  the  cornea  or  a  wound,  or  it  may  be  slow  in  forming,  and  in\'olve 
nearly  or  quite  the  whole  of  the  cornea,  pushing  it  forward  in  the  shape  of  a  cone; 
this  is  called  conical  coniea.  Posterior  staphyloma  occurs  in  near-sighted  people,  the 
anteroposterior  diameter  of  the  eye  being  longer  than  normal.  If  this  posterior 
staphyloma  or  stretching  of  the  eye  becomes  marked,  the  choroid  atrophies  and  the 
functions  of  the  retina  are  lost.  The  white  sclera  is  seen  with  the  ophthalmoscope, 
surrounding  or  to  one  side  of  the  optic  nerve. 

Although  the  cornea  has  no  blood-vessels,  it  still,  from  its  exposed  position, 
becomes  inflamed  {keratitis')  and  ulcerated,  and  eventually  blood-vessels  may  de- 
velop into  it  from  its  periphery,  constituting  the  disease  known  as  pannus. 

The  weakest  portion  of  the  globe  is  at  the  junction  of  the  sclerotic  coat  with  the 
cornea.  It  is  here  that  the  sclera  is  thinnest.  On  this  account,  blows  on  the  eye 
cause  it  to  rupture  usually  at  this  point,  the  tear  encircling  the  edge  of  the  cornea 
for  a  variable  distance  (usually  at  its  upper  and  inner  quadrant)  according  to  the 
force  and  direction  of  the  injury.      On  healing,  a  staphyloma  may  form  at  this  point. 

The  choroid  or  vascular  coat  of  the  eye  contains  the  pigjnent  or  color  of  the 
eye.  It  is  continued  forward  as  the  ciliary  body  (or  processes)  and  iris.  Being  a 
vascular  tissue,  its  diseases  are  inflammatory.  If  the  choroid  is  affected  we  have 
choroiditis;  if  the  ciliary  region  is  inflamed,  it  is  called  cyclitis ;  and  if  the  iris  is 
inflamed  we  have  iritis. 

The  retina  or  nervous  coat  of  the  eye  is  concerned  in  the  function  of  sight  and 
it,  like  other  nerves,  may  be  affected  with  inflammation,  called  retinitis.  Sometimes 
it  becomes  loosened  from  the  choroid  beneath  by  a  hemorrhage  or  rapid  stretching 
of  the  sclera,  constituting  a  detachment  of  the  retina.  Outside  the  disk  is  the  macula 
lutea  and  fovea  centralis  or  region  of  distinct  vision. 

Filling  the  interior  of  the  eye  is  the  jelly-like  transparent  vitreous  hiwior^  enclosed 
in  the  hyaloid  membrane.  In  front  of  the  vitreous  humor  is  the  lens;  and  the  clear, 
limpid  liquid  between  the  anterior  surface  of  the  lens  and  the  posterior  surface  of  the 
cornea  is  the  agueoiis  humor. 

The  lens,  immediately  behind  the  iris,  is  suspended  in.  its  capsule  from  the 
ciliary  processes  by  its  suspensory  ligament  or  zone  of  Zinn.  Between  the  ciliary 
processes  and  the  sclera  lies  the  ciliary  muscle,  which  regulates  the  accommodation 


78 


APPLIED   ANATOMY. 


or  focussing  power  of  the  eye.  The  ciliary  processes  are  formed  of  convolute! 
blood-vessels  supported  by  connective  tissue  and  covered  by  the  pigmented  exten- 
sion of  the  retina.  This  ciliary  region  is  an  exceedingly  sensitive  one  and  a  serious 
wound  of  it  usually  means  a  loss  of  the  eye. 

Cataract. — When  the  lens  is  opaque  it  constitutes  the  disease  known  as  cata- 
ract: this  name  is  also  applied  to  opacities  of  the  capsule  of  the  lens.  When  the  lens 
alone  is  opaque  it  is  called  a  le7iticular  cataract;  when  the  capsule  alone  is  affected,  it 
is  a  capsular  cataract.  Both  are  sometimes  involved,  constituting  a  lenticiilocapsular 
cataract.  The  lens  is  made  up  of  layers  like  an  onion.  Some  of  these  layers  may 
become  opaque,  leaving  a  surrounding  rim  of  clear  tissue.  The  nucleus  within  the 
affected  layer  is  also  clear.  This  form  is  called  a  zonular  or  lamellar  cataract.  A 
capsular  cataract  may  affect  the  anterior  portion  of  the  capsule,  forming  an  anterior 
polar  cataract^  or  the  posterior  layer  of  the  capsule,  forming  a  posterior  polar  cataract. 

If  the  cornea  has  been  perforated  by  a  central  ulceration,  the  aqueous  humor 
escapes,  the  lens  falls  forward,  and  its  anterior  capsule  becomes  adherent  at  the  site 


Lens 


Suspensory  ligament  of  lens 
Canal  of  Schlemm 
Ciliary  process 

Conjunctiva 


Cornea 

Anterior  chamber 
Iris 

Posterior  chamber 

Sclerocorneal  juncture 


Tendon  of  in 

ternal  rectus 

muscle 

Vena  vorticosa 


Tendon  of 
-external  rectus 
muscle 


Vitreous 


Sclera 


Ciliary  nervi 

Posterior  ciliary  vessels 

Hyaloid  canal 

optic  nerve 

Central  retinal  vessels 


Choroid 


Retina 
Fovea  centralis 


Fig.  93. — Diagrammatic  horizontal  section  of  right  eye.    X  3^^-     (Piersol.) 


of  perforation.  As  the  aqueous  humor  reaccumulates,  it  pushes  the  lens  back,  leaving 
a  small  portion  of  inflammatory  tissue  clinging  to  its  anterior  capsule,  thus  forming 
an  anterior  polar  cataract.  A  posterior  polar  cataract  is  the  result  either  of  disease, 
such  as  choroiditis^  in  which  the  posterior  capsule  becomes  involved,  or  of  a  persistence 
of  the  remains  of  the  hyaloid  artery,  a  fetal  structure. 

Secondary  cataracts  are  the  opacities  of  the  capsule  or  inflammatory  bands 
and  tissues  which  are  left,  or  which  occur,  after  the  removal  of  the  lens.  The  lens  in 
childhood  is  soft;  it  grows  harder  as  age  increases.  If  the  aqueous  humor  obtains 
access  to  the  lens  through  a  wound  of  the  anterior  capsule,  the  lens  becomes  opaque, 
constituting  a  traumatic  cataract.  In  operating  for  cataract  in  childhood,  the  lens, 
being  soft,  is  first  rendered  opaque  by  the  aqueous  humor  admitted  through  a 
puncture  made  in  the  capsule  ;  if  it  is  admitted  repeatedly  to  the  lens  by  the 
surgeon's  needle  (needling  or  discission  operation)  the  lens  matter  is  completely 
dissolved.  The  fluid  lens  matter  can  also  be  removed  by  a  suction  instrument. 
In  old  people  the   nucleus  becomes  hard  and  opaque,  forming  a  senile  cataract. 


REGION   OF   THE    EYE. 


79 


The  aqueous  humor  does  not  dissolve  the  opaque  lens  after  the  aj^e  of  thirty  five 
years.  Senile  cataract  rarely  occurs  before  the  forty-fifth  year,  so  there  is  a  period 
of  ten  years  in  which  a  cataract  may  be  a  nuclear  cataract  without  being  senile. 

To  remove  a  nuclear  or  a  senile  cataract,  a  slit  is  made  through  the  cornea  near 
its  scleral  junction,  a  piece  of  the  iris  may  (or  may  not)  be  removed,  the  anterior 
capsule  is  cut  with  a  cystotome  and  the  opaque  lens  pressed  out  through  the 
opening  so  made,  then  through  the  pupil  (either  artificial  or  dilated  with  atropine), 
and  finally  through  the  sclerocorneal  incision.  The  posterior  capsule  is  not  injured, 
and  it  prevents  the  vitreous  humor  from  escaping.  If  inflammation  follows  the 
operation,  the  iris  and  ciliary  region  throw  out  lymph  and  the  remains  of  the 
capsule  become  opaque,  forming  a  secondary  or  capsular  cataract.  This  is  removed 
by  tearing  or  cutting  it  across  with  needles  or  extremely  fine  scissors. 

Iris. — The  iris  is  the  continuation  of  the  choroid  through  the  ciliary  body,  and 
extends  down  to  the  pupil,  its  free  edge  resting  on  the  anterior  surface  of  the  lens. 
The  iris  is  composed  of  a  vascular  and  fibrous  anterior  portion,  and  a  muscular  and 
pigmented  posterior  portion.  In  consequence  of  its  vascularity,  the  iris  is  the  fre- 
quent site  of  inflammation.  When  inflamed  it  pours  out  lymph  which  may  cause  it 
to  adhere  to  the  lens  behind,  forming  a  posterior  synechia.  An  anterior  synechia  is 
where,  on  account  of  a  perforation  of  the  cornea,  the  iris  washes  forward  and  becomes 
attached  to  the  cornea  in  front. 

The  circular  muscle  fibres  surrounding  the  pupil  are  anterior,  and  form  the 
sphincter  piipillcE  muscle ;  it  contracts  the  pupil.  The  radiating  muscular  fibres, 
which  lie  posteriorly,  form  the  dilator  piipillce  ;  it  dilates  the  pupil.  The  dark  pig- 
ment layer  is  on  the  posterior  surface  of  the  iris,  and  after  an  attack  of  iritis,  as  the 
adherent  iris  is  torn  loose  from  the  lens,  it  leaves  patches  of  pigment  adhering  to  the 
anterior  capsule. 

The  iris,  as  it  rests  at  its  pupillary  margin  on  the  lens,  divides  the  space  anterior 
to  the  lens  into  two  parts.  The  part  between  the  posterior  surface  of  the  iris  and  the 
anterior  surface  of  the  lens  forms  the  posterior  chamber.  The  anterior  chamber  lies 
between  the  anterior  surface  of  the  iris  and  the  posterior  surface  (^Descemet^ s  mem- 
brane) of  the  cornea.  The  two  chambers  communicate  through  the  pupil.  The 
anterior  surface  of  the  iris  toward  its  periphery  is  of  the  nature  of  a  coarse  mesh- 
work,  the  spaces  of  which  are  the  spaces  of  Fonta^ia.  They  communicate  with  a 
venous  or  lymph  canal  which  passes  around  the  eye  at  the  sclerocorneal  junction 
(^canal  of  Schlemm ). 

Aqueous  Humor  and  Anterior  Lymph  Circulation, — The  aqueous  humor 
is  of  the  nature  of  lymph.  It  is  secreted  by  the  ciliary  processes  and  posterior  surface 
of  the  iris.  It  passes  through  the  pupil  to  the  anterior  chamber,  and  enters  the 
spaces  of  Fontana  to  empty  into  the  canal  of  Schlemm.  The  canal  of  Schlemm 
empties  its  contents  into  the  anterior  ciliary  veins.  In  iritis  and  glaucoma  the  lymph- 
current  is  seriously  interfered  with.  In  iritis,  the  swelling  and  outpouring  of  lymph 
blocks  the  spaces  of  P^ontana  and  prevents  a  free  exit  of  the  aqueous  humor  from 
the  anterior  chamber,  therefore  in  this  condition  the  anterior  chamber  is  deep,  and 
the  iris  is  seen  to  lie  far  beneath  the  cornea. 

Glaucoma. — Glaucoma  is  a  disease  accompanied  by  increased  intra-ocular 
tension.  The  eyeball  feels  hard  to  the  touch.  It  is  supposed  to  be  due  to  disease 
of  the  ciliary  region  interfering  with  the  canal  of  Schlemm  and  obstructing  it. 
Therefore,  the  drainage  of  the  eye  and  the  circulation  of  the  aqueous  humor  is  inter- 
fered with.  In  iritis  the  anterior  chamber  becomes  deeper,  but  in  glaucoma,  as  the 
intra-ocular  tension  increases,  it  pushes  the  lens  forward,  and  it  is  seen  to  lie  close 
up  to  the  cornea;  so  that  a  shallow  anterior  chamber  causes  the  ophthalmologist  to 
suspect  glaucoma  and  a  deep  anterior  chamber  iritis.  The  increased  pressure  within 
the  eye  pushes  the  optic  nerve  backward  at  its  point  of  entrance,  so  that  it  is  seen 
sunk  below  the  surface  of  the  adjoining  retina,  forming  a  distinct  cup-shaped  cavity 
or  pit.      This  is  cuppino;  of  the  disk. 

Optic  Nerve. — The  optic  nerve  reaches  from  the  optic  chiasm,  to  the  eyeball,  a 
distance  of  about  5  cm.  f  2  in. ) .  It  enters  the  apex  of  the  orbit  through  the  optic  foramen 
at  the  upper  inner  angle,  in  company  with  the  ophthalmic  artery.  The  artery  crosses 
the  under  surface  of  the  nerve  from  its  inner  to  its  outer  side.      The  optic  nerve  has 


8o 


APPLIED    ANATOMY. 


as  its  covering  a  prolongation  of  the  membranes  of  the  brain.  The  dura  mater 
when  it  reaches  the  foramen  spHts  and  gives  one  layer  to  form  the  periosteum  lining 
the  orbit  and  the  other  to  form  a  fibrous  sheath  of  the  nerve.  This  arrangement 
prevents  pus,  forming  in  the  orbit,  from  passing  through  the  optic  foramen  into 
the  skull.  The  artcria  centralis  rctince  enters  the  nerve  on  its  under  side  and  passes 
through  its  centre  to  the  interior  of  the  eye.  The  nerve  itself  is  covered  with  a  fine 
pial  membrane  and  an  arachnoid  separating  it  from  the  dura,  thus  forming  subdural 
and  subarachnoid  spaces.  As  these  membranes  and  spaces  are  continuous  with  those 
of  the  brain,  hemorrhage  or  serous  efiusions  occurring  within  the  brain  can  thus  find 
their  way  into  the  sheath  of  the  nerve. 

As  the  nerve  enters  the  eye,  it  is  contracted  and  forms  the  optic  disk  or  papilla. 


Cornea 


Greater  arterial  ring 
Iris 

Lesser  arterial  ring 

Ciliary  process 


Canal  of  Schlemm 

^Corneal  loop 


Perforating  branch 

Conjunctival  vessels 


Communication  between 


Anterior  ciliary  vessels 


Sclera 
Episcleral  vessels 


choroidal  and  optic  vessels 
Central  retinal  vessels 


Vena  vorticosa 

Supplying  choroid 

Short  posterior  ciliary  artery 

Long  posterior  ciliary  artery 
Communicating  twig 
Inner  sheath  vessels 
Outer  sheath  vessels 


Communication  between  optic 
and  sheath  vessels 


I 


Fig  94. — Diagram  illustrating  circulation  of  eyeball.    (Leber.) 


It  is  readily  seen  with  the  ophthalmoscope  as  a  round  spot  somewhat  lighter  in  color 
than  the  surrounding  eyeground.  Coming  from  a  depression  or  cup  in  the  disk, 
called  the  poms  opticus,  are  the  retinal  arteries  and  veins.  A  certain  amount  of 
cupping  is  normal,  but  if  wide  and  deep,  with  overhanging  edges  over  which  the 
vessels  can  be  seen  to  dip,  it  is  indicative  of  glaucoma. 

Sometimes  the  papilla  or  disk  is  swollen,  constituting  an  optic  neuritis. 
In  brain  tumor  this  is  frequently  the  case  and  is  called  choked  disk,  or  '  'stauung 
papilla'''  so  named  because  the  circulation  was  thought  to  be  interfered  with  owing 
to  the  intracerebral  pressure  being  transmitted  directly  to  the  nerve.  On  the  sub- 
sidence of  a  severe  neuritis  the  nerve  is  left  in  a  state  of  optic  atrophy  and  blindness 
is  the  result. 


FIG.  95. 


NORMAL  HUMAN   FUNDUS  OCULI,  SHOWING  OPTIC   PAPILLA  AND   BLOOD  VESSELS;  ALSO  THE  MACULA   UUTEA. 
DRAWN    BY   MR.   LOUIS    SCHMIDT. 


REGION    OF   THE    EYE.  8i 

Muscles  of  the  Orbit.  —  Six  muscles  are  connected  with  the  eyeball, 
four  straight  and  two  oblique.  One  muscle,  the  levator  palpebrce,  goes  to  the 
lid.  The  four  recti  muscles,  superior,  mferior,  external,  and  hiternal,  arise  from  a 
common  tendinous  origin,  forming  a  ring  or  tube  called  the  ligament  of  Zinn. 
This  ligament  or  tube  surrounds  the  optic  foramen  and  is  attached  to  the  opposite 
side  of  the  sphenoidal  fissure.  Through  it  run  the  optic  nerve  and  ophthalmic  artery, 
the  third,  fourth,  and  the  nasal  branch  of  the  ophthalmic  (fifth)  nerve. 

The  levator  paipebrce  and  superior  oblique  arise  to  the  inner  side  and  above  the 
optic  foramen  close  to  the  origin  of  the  other  muscles.  The  superior  oblique,  after 
passing  through  its  trochlea  or  pulley  at  the  inner  upper  angle  of  the  orbit,  continues 
downward,  backward,  and  outward  between  the  superior  rectus  and  the  eye,  to  be 
inserted  above  the  extremity  of  the  inferior  oblique. 


Ethmoidal  cells 


Sphenoidal  sinus 


Superior  oblique 
muscle 


Superior  rectus 
muscle 


Levator  palpebrae 
superior  muscle 


Superior  ophthal- 
mic vein 


Lachrymal  gland 


Fig.  96. — The  roof  of  the  orbit  has  been  removed,  showing  the  contents. 

The  inferior  oblique  arises  from  the  anterior  edge  of  the  orbit  just  to  the  outer 
side  of  the  lachrymal  groove.  It  passes  outward,  upward,  and  backward,  over 
the  external  surface  of  the  inferior  rectus,  to  be  inserted  beneath  the  external  rectus. 

The  recti  muscles  insert  into  the  sclera  5  to  7  mm.  back  from  the  cornea.  In 
the  operation  for  internal  squint  or  strabismus,  the  internal  rectus  muscle  is  cut. 
It  possesses  the  longest  tendon  of  insertion,  while  the  external  possesses  the  shortest. 
The  recti  muscles  pull  the  eyes  toward  their  respective  sides.  The  superior  oblique 
turns  the  cornea  down  and  out  and  rotates  it  inwardly.  The  inferior  oblique  turns 
the  cornea  up  and  slightly  out  and  rotates  the  eye  outward.  A  disarrangement  of  any 
of  these  muscles  produces  diplopia  or  double  vision. 

Blood-Vessels  of  the  Orbit. — The  arteries  of  the  orbit  are  derived  from  the 
ophthalmic  artery,  which  breaks  up  into  its  various  branches  soon  after  it  passes  through 
the  optic  foramen.  In  enucleation  of  the  eye  there  is  practically  no  bleeding, 
because  the  arteria  centralis  is  the  only  one  divided,  and  it  is  small.  In  evisceration, 
or  cleaning  out  of  the  contents  of  the  orbit,  the  main  trunk  of  the  ophthalmic  will 
not  be  cut  unless  the  very  apex  is  invaded.  Hemorrhage  is  readily  controlled  by 
packing  gauze  into  the  orbital  cavity. 

The  veins  of  the  orbit  are  the  sjiperior  and  inferior  ophthalmic.  The  former  is 
much  the  larger  and  more  important.  It  not  only  drains  the  upper  portion  of  the 
orbit,  but  communicates  directly  with  the  angular  branch  of  the  facial,  at  the  inner 
canthus  of  the  eye.  The  infection  of  erysipelas  sometimes  travels  along  these  veins 
directly  from  the  nose,  face,  and  scalp  without,  to  the  cavernous  sinus  and  meninges 
6 


82  APPLIED    ANATOMY. 

within,  causing  thrombosis  and  death.  The  inferior  ophthalmic  usually  empties  into 
the  superior;  its  anastomoses  at  the  anterior  portion  of  the  orbit  with  the  veins  of 
the  face  are  much  smaller  and,  therefore,  not  nearly  so  dangerous. 

Nerves  of  the  Orbit. — The  optic  nerve  is  the  nerve  of  sight.  Interference 
with  it  produces  blindness.  The  oculomotor  or  third  nerve  supplies  all  the  muscles 
of  the  orbit  except  the  external  rectus  and  superior  oblique.  If  paralyzed,  the  eye 
cannot  be  mo\'ed  upward,  inward,  or  to  any  extent  downward.  There  will  be  ptosis 
of  the  upper  lid  from  paralysis  of  the  levator  palpebr^e,  and  dilatation  of  the  pupil  and 
paralysis  of  the  accommodation  of  the  eye.  If  the  sixth  or  abducens  is  paralyzed,  the 
eye  cannot  be  turned  outward.  If  the  fourth  or  pathetic  is  paralyzed,  the  superior 
oblique  fails  to  act,  and  the  double  vision  produced  is  w^orse  when  the  patient  looks 
down,  because  it  is  normally  a  depressor  muscle.  The  lachrymal,  frontal,  and  nasal 
bra7iches  of  the  fifth  are  nerves  of  sensation,  hence,  in  supra-orbital  neuralgia  and  that 
affecting  the  nasal  branch,  pain  is  felt  in  the  orbit  at  the  inner  angle  of  the  eye  and 
down  the  side  of  the  nose. 

Retina. — On  the  interior  of  the  eye,  the  expansion  of  the  optic  nerve  forms  the 
retina.  The  retina  is  divided  into  two  lateral  halves,  each  supplied  by  a  corre- 
sponding half  of  the  optic  nerve.  When  the  nerve  reaches  the  optic  chiasm  it  splits 
into  two  parts,  one  (internal  fibres)  going  to  the  opposite  side  of  the  brain,  and 
the  other  (external  fibres)  to  the  ganglia  on  the  same  side  of  the  brain.  Posterior 
to  the  chiasm,  the  nerve  fibres  form  the  optic  tracts.  The  optic  tracts,  after  leaving 
the  chiasm,  wind  around  the  crura  cerebri  to  the  external  geniculate  bodies,  thence 
they  pass  to  the  thalami  and  anterior  corpora  quadrigemina,  and  are  continued  back- 
ward into  the  cuneus  lobule  of  the  occipital  lobe  of  the  brain. 

It  will  thus  be  seen  that  a  lesion  affecting  any  portion  of  the  optic  pathway  pos- 
terior to  the  chiasm  will  produce  blindness  of  one-half  of  the  retina  of  both  eyes  on 
the  side  of  the  injury;  a  right-sided  lesion  will  produce  blindness  of  the  right  half  of 
both  retinae,  and  a  lesion  on  the  left  side,  blindness  of  the  left  half  of  both  eyes.  This 
is  called  hemianopia.  It  is  right  lateral  hemianopia  if  the  right  half  of  the  visual  fields 
is  aflected,  and  left  lateral  if  the  left  sides  are  allected.  Affections  of  the  optic  nerve 
produce  total  blindness  of  that  eye  if  the  whole  nerve  is  involved.  If  only  a  part  is 
involved,  then  a  tmilateral  hc^nianopia  may  ensue.  A  bite77iporal  hemiariopia  may  be 
caused  by  a  tumor  involving  the  anterior  or  middle  portion  of  the  chiasm.  A  binasal 
hemianopia  requires  a  symmetrical  lesion  on  the  outer  side  of  both  optic  nerves  or 
tracts.  A  brain  tumor  located  in  the  cuneus  lobule  would  cause  a  lateral  hemianopia  of 
the  same  side,  right  or  left,  of  both  visual  fields,  hence  sometimes  called  homonymous. 

The  Eyelids  and  Conjunctiva. — The  eyelids  are  composed  of  five  layers, 
viz:  {i)  ski?i,  (2)  subcidaneons  tissue,  (3)  orbicularis  palpebrarum  vuiscle,  (4) 
tarsal  cartilage  with  the  contained  Meibomian  glands,  (5)  the  conjunctiva.  The 
juncture  of  the  two  lids  at  each  end  is  called  the  inner  and  outer  canthus. 

The  skin  of  the  lids  is  thin  and  the  subcutaneous  tissue  loose  and  devoid  of  fat. 
For  these  reasons  blood  finds  its  way  readily  into  the  lids  and  shows  plainly  beneath  the 
skin,  constituting  the  familiar  "black  eye."  The  skin  lends  itself  readily  to  plastic 
operations,  as  it  is  easily  raised  and  the  gap  left  can  be  readily  closed.  The  blood 
supply  of  the  lids  is  abundant,  so  that  the  flaps  are  well  nourished  and  sloughing  is 
not  apt  to  occur.  The  folds  in  the  skin  run  parallel  to  the  edge  of  the  lids,  therefore 
the  incisions  should  be  made  as  much  as  possible  in  the  same  direction.  The 
orbicularis  palpebrarum  muscle  passes  circularly  over  the  lids  and  lies  on  the  tarsal 
cartilage  toward  the  edge  of  the  lids  and  on  the  orbitotarsal  ligament  above.  The  so- 
called  tarsal  cartilage  or  plate  is  composed  of  dense  connective  tissue  and  contains  no 
cartilage  cells.  It  is  attached  externally  by  the  external  {lateral)  palpebral  ligament 
and  internally  by  the  internal  {medial)  palpebral  ligament  or  tendo-oculi.  This  latter 
passes  in  front  of  the  lachrymal  sac.  The  tarsal  plate  is  continued  to  the  rim  of  the 
orbit  by  the  orbitotarsal  ligarnent  or  septiwi  orbitale.  The  expansion  of  the  levator 
palpebrae  muscle  ends  in  the  upper  edge  of  the  tarsal  cartilage  and  sends  some  fibres 
to  the  tissues  immediately  in  front.  The  orbitotarsal  ligament  and  tarsal  cartilage 
prevent  the  fat  of  the  orbit  from  protruding  and  also  act  as  a  barrier  to  the  exit  of  pus. 

The  tarsal  cartilage  contains  the  Meibomian  glands.  These  can  be  seen  in  life, 
by  everting  the  lid,  as  yellow  streaks  passing  backward  from  the  edge  of  the  lids. 


REGION    OF   THE    EYE. 


83 


Frequently  these  glands  become  obstructed  and  their  mucus  contents  dilate  the 
gland,  forming  a  cyst  known  as  chalazion.  Suppuration  may  occur  and  pus  instead 
of  mucus  is  then  contained  within  them.  The  wall  of  these  cysts  is  formed  by 
fiDrous  tissue  containing  some  of  the  epithelial  cells  of  the  glands;  therefore,  if  an 
uninflamed  cyst  is  simply  opened  and  its  contents  expressed,  it  will  soon  reform. 
To  prevent  this  recurrence,  the  lining  membrane  is  curetted  in  order  to  remove  the 
mucus-forming  cells.  The  cyst  may  point  and  be  opened  either  on  the  side  of  the 
skin  or  conjunctiva,  preferably  the  latter. ' 

The  openings  of  the  Meibomian  ducts  are  on  the  inner  edge  of  the  lids  where 
the  conjunctiva  joins  the  skin.  At  the  outer  edge  of  the  lids  are  the  cilice  or  eye- 
lashes and  connected  with  them  are  sebaceous  and  sweat  glands.      Infection  of  these 


Skin 
/  Subcutaneous  tissue 

Orbicularis  p  ilpebrarum 
E-at 


superior 
Blood-vessel 

Henle's  gland 


Duct  in  tarsal  plate 


Artery  of  tarsal  arch 


Meibomian  duct 


Glands  of  Moll  Cilia  Ciliary  muscle 

Fig.  97.— Vertical  section  of  upper  eyelid  of  child.    X  15.     (Piersol.) 


glands  produces  a  small  abscess  called  a  stye.  As  they  are  on  the  outer  edge  of  the 
lids  they  tend  to  discharge  anteriorly  and  not  toward  the  conjunctiva. 

The  co?iju7ictiva  covers  the  outer  surface  of  the  eye  and  the  inner  surface  of 
the  lids.  The  fold  where  it  passes  from  one  to  the  other  is  called  the  fornix.  The 
tarsal  or  palpebral  co7ijunctiva  adheres  closely  to  the  tarsus  and  as  it  is  transparent 
the  Meibomian  glands  can  readily  be  seen  through  it.  The  ocular  or  bulbar  coft- 
junctiva  is  loosely  adherent  to  the  sclerotic  coat  and  through  it  the  conjunctival  vessels, 
w'hich  move  with  it,  can  be  seen.  The  straight  vessels  going  toward  the  cornea  do 
not  move  when  the  coniunctiva  is  moved,  because  they  lie  deeper  and  are  attached  to 
the  sclera. 

The  Lachrymal  Apparatus. — The  lachrymal  gland  cor\s\^\.s  of  two  portions: 
an  orbital   or  superior  portion    and  a   palpebral  or  inferior  portion.      The  orbital 


84 


APPLIED    ANATOMY. 


portion  is  enclosed  in  a  capsule  and  slung  from  the  orbital  margin  by  its  suspensory- 
ligament.  Beneath,  it  rests  on  the  fascial  expansion  of  the  levator  palpebree  muscle. 
The  palpebral  portion  is  smaller  than  the  orbital  and  is  partially  separated  from  it  by 
the  fascial  expansion.  It  lies  on  the  conjunctiva  at  the  upper  and  outer  portion  of 
its  fornix.  The  lachrymal  gland  opens  by  several  fine  ducts  into  the  fornix  of 
the  conjunctiva.  It  is  sometimes  the  seat  of  malignant  tumors,  but  rarely  of  other 
troubles.  The  remaining  lachrymal  passages  running  from  the  eye  to  the  nose  are 
frequently  the  seat  of  inflammation,  causing  suppuration  and  obstruction. 

T\\Qpiinda  lachryvialia  in  the  top  of  each  papilla  lead  into  the  canaliculi.  These 
enter  the  lids  perpendicular  to  their  margin  and  turning  at  right  angles  join  just 
before  entering  the  upper  end  of  the  lachrymal  sac. 

The  lachrymal  canal,  embracing  the  sac  and  lachrymonasal  duct,  each  about 
12  mm.  in  length,  extends  from  just  above  the  internal  tarsal  ligament  or  tendo  oculi 
to  the  inferior  meatus  of  the  nose.  The  sac  is  strengthened  posteriorly  by  the  tensor 
tarsi  or  muscle  of  IIor?ier,  which  passes  from  the  lachrymal  bone  to  the  pujicta,  and 
by  some  fibres  of  the  palpebral  ligament.  Anteriorly  is  the  strong  palpebral  liga- 
ment. Below  the  palpebral  ligament,  the  sac  is  comparatively  weak  and  here  it  is 
that  distention  occurs  and  pus  makes  its  exit.  The  duct  lies  in  the  lachrymal  groove 
in  the  bone.     It  is  narrower  than  the  sac,  being  3  to  4  mm.  in  width,  and  is  the  usual 


Lachrymal  gland 


Lachrymal  sac 

Lachrymonasal  duct 


Inferior  meatus 


'■y^/         ^  Inferior  turbinate 
Fig.  98. — Lachrymal  apparatus. 


seat  of  obstructions.  To  keep  the  passage  open  in  case  of  stricture  probes  are 
passed.  The  direction  of  the  duct  is  slightly  outward  and  more  markedly  backward, 
being  indicated  approximately  by  a  line  drawn  from  the  inner  canthus  to  just  behind 
the  second  premolar  tooth.  In  probing  the  duct  it  is  customary  to  first  open  the 
punctum  in  the  lower  lid — which  is  normally  only  one  mm.  in  size — by  slitting  it  and 
the  caniculus  with  a  Weber's  canaliculus  knife.  The  probe  is  directed  horizontally 
until  the  sac  is  entered,  which  is  recognized  by  the  end  of  the  probe  striking  the 
bone;  it  is  then  raised  vertically  and  passed  downward  and  backward  and  sometimes 
slightly  outward  until  it  can  be  seen  in  the  inferior  meatus  of  the  nose  about  i  cm. 
behind  the  anterior  end  of  the  inferior  turbinated  bone. 


THE   EAR. 

The  external  auditory  meatus,  the  tympanum.,  and  the  Eustachian  tube  are  the 
remains  of  the  first  branchial  cleft  in  the  foetus.  A  failure  of  any  portion  of  the  cleft 
to  close  normally  may  leave  small  sinuses  or  depressions  in  the  neighborhood  of  the 
ear.  The  external  ear,  also  called  the  auricle  or  pinna,  is  composed  mainly  of  a 
cartilaginous  framework  covered  with  thin  skin;  the  lobe  or  lobide  forms  its  lower 
part  and  is  composed  of  dense  connective  tissue  containing  fat.  The  large  concav- 
ity leading  into  the  meatus  is  the  concha.     The  skin  of  the  ear  is  thin  and  moder- 


THE    EAR. 


85 


ately  firmly  attached  to  the  cartilage.  The  subcutaneous  tissue  contains  little  or 
no  fat.  Although  well  supplied  with  blood,  the  expo.sed  condition  of  the  blood-vessels 
renders  the  ear  sensitive  to  cold,  and  frost-bites  are  common.  Injuries  and  wounds 
of  the  cartilage  are  slow  to  heal,  and  if  inflamed  the  cartilage  becomes  exceedingly 
sensitive.  Swelling  of  the  ear  readily  occurs  from  injury  or  erysipelas,  and  the  tension 
is  quite  painful. 

Helix 
Fossa  scaphoidea 


Crus  antihelix  superius 
Fossa  triangularis 

Crus  antihelix  inferius 

Tragus 
Incisura  intertragica 


Tuberculum  superius 


Lobule 


Fig.  gq. — The  external  ear. 

HcBmatoma  aiiris,  or  effusions  of  blood,  occur  from  traumatism,  especially  in  the 
msane.  While  a  h^ematoma  may  occur  between  the  skin  and  perichondrium,  on 
account  of  the  firm  binding  of  the  skin  to  the  cartilage  it  is  usually  between  the 
perichondrium  and  cartilage. 

Angioma,  or  enlargement  of  the  blood-vessels,  not  infrequently  affects  the 
external    ear   and    may  not   only  be   disfiguring   but,    by  showing   a    tendency   to 


Chorda  tympani 
Facial  nerve 


'-■^,  /""L—  Internal  ai'.ditorv  meatus 


Semicircular  canals 


Jugular  vein 


Fig.   icx) — Vertical  section  of  the  right  ear. 


extension,  may  demand  operation.  The  external  ear  derives  its  blood  supply  from 
the  auricular  branches  of  the  temporal,  internal  maxillary,  posterior  auricular,  and 
occipital  arteries.  As  these  are  all  branches  of  the  external  carotid,  that  artery  is 
sometimes  tied  as  a  preliminary  step  to  excising  the  angiomatous  vessels. 

The  External  Meatus. — The   external  auditory   meatus  extends   from    the 
concha  to  the  drumhead,  and  is  about  2.5  cm.  in  length.     A  little  less  than  one-half 


86 


APPLIED    ANATOMY. 


of  it  is  cartilaginous  and  a  little  over  one-half  bony.  Viewed  anteroposteriorly  the 
canal  has  a  slight  curve  with  its  convexity  upward  (Fig.  loo).  Viewed  from  above 
(Fig.  loi ),  it  is  seen  first  to  pass  backward  and  then  forward,  forming  an  angle  before 
the  bony  wall  is  reached.  In  order  to  look  into  the  ear  and  see  the  membrane  it  is 
necessary  to  straighten  the  canal,  either  by  inserting  a  speculum  or  by  pulling  the 
auricle  outward,  upward,  and  backward.  In  children,  upward  traction  is  not  so 
necessary  as  in  the  adult.  The  length  of  the  canal  is  approximately  the  same  in  child- 
hood as  in  adults,  but  the  bony  part  is  still  in  a  cartilaginous  condition.  The  external 
opening  is  oval,  while  farther  in  the  canal  is  more  circular;  hence  the  Gruber  speculum, 
which  is  oval  in  shape,  or  the  round  speculum  of  Wilde  can  be  used  with  almost 
equal  satisfaction.  The  point  of  junction  of  the  bony  and  cartilaginous  parts  is 
narrower  than  either  end,  and  it  is  difficult  to  remove  a  foreign  body  which  has 
passed  this  point.  This  is  particularly  true  in  children,  the  lumen  of  the  external 
meatus  being  quite  small  and  narrow  while  the  tympanic  membrane  is  nearly  as 
large  as  in  adults. 

The  floor  is  longer  than  the  roof,  owing  to  the  drum  membrane  inclining  at  an 
angle  of   140  degrees.      Cartilage  forms  the  lower  part  of  the  canal,  while  the  upper 


Carotid  canal        Eustachian  tube 


Glenoid  cavity 


Internal  auditory  meatus 


Membrana  t>nipaiii 

Facial  canal 


I 


Ceruminous  glands 


Fig.  ioi. — Right  ear;  horizontal  transverse  section 


part  is  completed  by  a  fibrous  membrane.  Below  and  in  front  is  the  temporomaxillary 
joint,''  and  just  posterior  is  Xh^  glenoid  lobe  of  the  parotid  gland.  When  the  gland  is 
inflamed  and  swollen  it  presses  on  the  cartilaginous  canal  and  produces  pain ;  and 
in  cases  of  suppuration  pus  may  discharge  through  the  external  meatus,  gaining 
access  to  the  canal  through  fissures  in  the  cartilage  called  the  fissures  of  Santorini. 
The  cartilaginous  portion  of  the  meatus  contains  sweat-glands,  sebaceous  glands,  and 
hair-follicles.  There  are  only  a  few  glands  in  the  upper  posterior  portion  of  the  bony 
meatus.  On  account  of  the  location  of  the  glands  in  the  external  portion  of  the  canal, 
accumulations  of  wax,  and  abscesses,  which  result  from  infection  of  the  glands,  occur 
nearer  to  the  surface  than  to  the  drum  membrane.  It  is  only  when  the  canal  begins  to 
fill  up  that  the  wax  pushes  its  way  to  the  membrane.  When  furuncles  occur,  the  lining 
membrane  swells  and  by  closing  the  canal  prevents  a  view  of  the  drum  being  ob- 
tained. Incising  of  furuncles  of  the  auditory  meatus  is  sometimes  required.  The 
site  of  the  inflamed  spot  having  been  located,  an  incision  can  be  made  where 
indicated.  If  care  is  exercised,  one  is  not  likely  to  injure  the  drum  membrane, 
because  the  abscess  starts  in  one  of  the  sebaceous  glands,  which  are  located  in  the 
external  half  of  the  meatus.  The  membrane  lies  2.5  cm.  from  the  surface,  and  the 
point  of  the  knife  should  not  be  carried  so  deeply  as  that  for  fear  of  wounding  it; 
there  is  no  necessity  of  going  so  far  inward. 


THE    EAR.  87 

The  meatus  is  supplied  by  the  auriculotemporal  braiich  of  the  fifth  and  the 
auricular  branch  of  the  pneumogastric  nerve.  Irritation  of  the  latter  nerve  is  said 
to  be  the  cause  of  feeling  it  in  the  throat  when  anything  is  put  in  the  ear. 

Membrana  Tympani. — The  niembrana  tympani  is  inclined  downward  and 
inward  at  an  angle  of  about  140°  to  the  upper  wall  (Troltsch)  and  27°  to  the  lower 
wall  (Bezold)  of  the  meatus  ;  it  does  not  lie  directly  trans\erse,  therefore  in  intro- 
ducing instruments  into  the  ear  the  upper  posterior  part  will  be  first  encountered. 
The  membrane  is  located  2.5  cm.  (i  in.)  from  the  surface;  this  is  to  be  borne  in 
mind  in  puncturing  the  membrane  or  other  operations.  The  membrane  has  three 
coats:  an  outer,  continuous  with  the  skin  of  the  meatus;  a  fibrous  or  middle  layer; 
and  an  internal  or  mucous  layer,  continuous  with  the  lining  of  the  tympanic  cavity. 
The  membrana  tympani  at  birth  is  fastened  at  its  circumference  to  the  tympanic 
bone,  which  unites  with  the  other  portions  of  the  temporal  bone  soon  after  birth. 
This  ring  of  bone  is  incomplete  at  its  upper  portion  for  a  distance  equaling  one-eighth 
of  its  circumference.  This  is  called  the  notch  of  Rivi?ius.  The  fibrous  layer  does 
not  extend  across  this  notch,  which  is  closed  by  the  mucous  membrane  on  the  inside 
and  by  the  skin  layer  of  the  membrane  on  its  outer  side.      The  part  closing  the  notch 

.Membrana  flaccida 


Short  process  of  malleus 


Long  handle  of  malleus 


Cone  of  light 
Fig.  102. — Outer  surface  of  the  tympanic  membrane  of  the  left  ear. 

is  called  ShrapnelV s  membrane  or  membrana  flaccida.  As  it  possesses  no  fibrous 
layer  it  is  weaker  than  the  membrane  elsewhere  and  consequently  is  a  favorite  spot 
for  pus  to  perforate  in  order  to  find  exit  from  the  middle  ear. 

In  examining  the  membrane  by  means  of  light  thrown  into  the  meatus  through 
a  speculum  by  the  head  mirror,  one  sees  extending  downward  from  its  centre  a  small 
cone  of  light;  any  depression  or  bulging  of  the  membrane  will  cause  this  cone  of 
light  to  be  altered  in  its  position,  or  even  cause  it  to  disappear  entirely.  From  the 
centre  of  the  membrane  upward  extends  a  line  which  indicates  the  attachment  of  the 
long  handle  of  the  malleus,  one  of  the  bones  of  the  middle  ear.  Stretching  across 
the  upper  portion  is  the  membrane  of  Shrapnell  or  membrana  flaccida,  so  called  on 
account  of  its  not  being  so  tense  as  the  remaining  portion.  It  is  better  supplied 
with  blood-vessels  than  the  other  portion. 

The  membrana  tympani  is  of  surgical  interest  on  account  of  its  being  often  dis- 
tended or  perforated.  A  purulent  discharge  from  the  ear  usually  indicates  disease 
of  the  middle  ear  or  tympanum.  If  pus  is  coming  from  a  furuncle  of  the  meatus,  the 
latter  will  be  swollen  and  its  source  can  readily  be  recognized.  If  it  comes  from 
outside  of  the  meatus,  as  in  cases  of  suppuration  of  the  parotid  gland,  it  will  be  recog- 
nized by  an  examination  of  the  gland.  There  is  no  other  source  of  pus  but  the 
middle  ear  and  for  it  to  gain  exit  it  must  perforate  the  membrane;  this  perforation 
can  usually  be  seen  with  the  speculum  and  head  mirror,  as  can  also  bulging. 

In  inflammation  of  the  middle  ear  the  effused  serum  or  pus  bulges  the  mem- 
brane outward.     When  this  condition  is  accompanied,  as  it  often  is,  by  intense  pain. 


88  APPLIED    ANATOMY. 

paracentesis  or  puncture  is  resorted  to.  The  preferable  spot  is  the  posterior  lower 
quadrant.  Paracentesis  of  the  membrane  should  be  done  by  beginning  the  incision  a 
little  above  and  behind  the  centre  of  the  tympanic  membrane,  which  slopes  downward 
and  forward  at  an  angle  of  140°  to  the  upper  wall,  and  cutting  downward  to  its 
lower  edge.  One  must  avoid  the  long  handle  of  the  malleus,  which  extends  directly 
upward  from  the  centre  of  the  membrane.  In  the  upper  posterior  part  are  the  incus 
and  stapes,  therefore  this  portion  should  be  avoided;  and  running  across  the  upper 
edge  beneath  the  mucous  membrane  is  the  chorda  tympani  nerve.  Division  of  this 
nerve  is  said  to  be  a  matter  of  not  much  account.  Incision  through  the  anterior  part 
is  not  considered  suitable  for  drainage. 

Perforations  frequently  occur  through  Shrapnell's  membrane  on  account  of  its 
not  having  any  fibrous  layer;  thus  the  pus  does  not  go  through  the  tympanic  mem- 
brane proper.  If  perforation  with  a  purulent  discharge  has  existed  for  a  long  time 
granulations  come  through  the  opening,  forming  an  aural  polyp.  To  remove  these 
a  snare  is  used  or  caustic  is  applied. 

The  Tympanum  or  Middle  Ear. — The  tympanic  cavity  is  flat  and  narrow 
and  is  situated  directly  behind  and  also  above  the  membrane.  It  has  a  floor  and 
roof,  and  external  and  internal  walls.  It  is  divided  into  the  portion  behind  the  mem- 
brane and  the  portion  above  the  membrane  called  the  attic.  The  floor  is  narrower 
than  the  roof  and  is  formed  by  the  tympanic  plate ^  which  separates  it  from  the  jugular 

Aditus 
Facial  nerve 

Oval  window 
Canal  for  tensor 

ni  muscle        Carotid  canal 


Euslachian  tube 

Tympanic  cavity 
Chorda  tympani  nerve 
Round  window 

Fig.  103. — Right  temporal  bone  : — The  outer  surface  has  been  cut  away,  exposing  the  tympanic  cavity,  its  inner  wall, 

the  mastoid  antrum,  Eustachian  tube,  etc. 

fossa  containing  the  commencement  of  the  internal  jugular  vein.  The  bone  forming 
the  floor  is  more  difficult  for  pus  to  perforate  than  is  that  of  the  roof,  so  that  exten- 
sion of  middle-ear  disease  is  less  frequent  through  it.  The  7-oof  is  comparatively 
thin  and  formed  of  cancellous  tissue  with  a  thin  and  weak  outside  compact  layer; 
therefore  it  is  a  somewhat  common  site  for  pus  to  perforate  and  thereby  obtain 
access  to  the  middle  fossa  of  the  skull.  The  distance  from  the  floor  to  the  roof  is 
approximately  15  mm.  (|  in.);  half  is  behind  the  membrane  and  the  rest  forms 
the  attic  above. 

The  external  wall  is  formed  below  by  the  tympanic  membrane  and  above  by 
the  bone.  As  the  membrane  is  the  weakest  portion  of  the  walls,  collections  of  pus 
in  the  middle  ear  most  often  find  a  vent  through  it.  Immediately  behind  the  mem- 
brane are  the  lower  portions  of  the  ossicles,  and  above  is  the  chorda  tympani  nerve. 

The  internal  wall  is  formed  of  bone  and  is  from  2  to  4  mm.  (yV  to  \  of  an 
inch)  behind  the  membrane.  It  is  so  close  that  in  doing  the  operation  of  para- 
centesis care  must  be  taken  not  to  thrust  the  knife  too  deeply.  In  it  are  the  oval 
and  round  windows  (Fig.  103). 

There  is  no  well-defined  anterior  or  posterior  wall.  The  anterior  portion  of  the 
cavity  is  continued  forward  into  the  Eustachian  tube;  the  canal  for  the  tensor 
tympani  muscle  is  immediately  above  it.  Posteriorly  the  cavity  of  the  attic  is  con- 
tinuous through  the  aditics  with  the  mastoid  antrum  and  the  cells  beyond.     Posterior 


THE    EAR. 


89 


to  the  opening  of  the  Eustachian  tube  is  an  elevation  on  the  internal  wall  called  the 
promonto7'y,  formed  by  one  of  the  semicircular  canals.  Above  the  promontory  is  the 
fenestra  ovalis,  which  lodges  the  stapes  bone  and  communicates  with  the  vestibule. 
Below  and  behind  is  the  fenestra  rotunda,  closed  by  a  membrane  separating  the 
cochlea  from  the  middle  ear.  Above  the  fenestra  ovalis  is  a  ridge  of  bone  marking 
the  aqueduct  of  Fallopius,  in  which  runs  the  facial  nerve. 

The  Eustachian  tube  passes  from  the  anterior  portion  of  the  tympanic 
cavity  downward,  forward,  and  inward  to  the  upper  posterior  portion  of  the  pharynx 
about  level  with  "the  floor  of  the  nose.  It  is  about  3.5  cm.  (approximately  i^  in.) 
in  length.  The  outer  third,  near  the  ear,  is  bony  and  the  inner  two-thirds  are 
cartilaginous.  The  point  of  junction  of  the  bony  and  cartilaginous  portions  is  the 
narrowest  portion  of  the  tube  and  is  called  the  isthmus.  The  tube  is  usually  closed, 
but  opens  in  swallowing,  yawning,  etc.,  thus  admitting  air  to  the  tympanic  cavity 
and  mastoid  cells.  Catarrhal  affections  of  the  throat  readily  travel  up  the  tube  and 
set  up  an  inflammation  of  the  middle  ear.  Swelling  of  the  lining  of  the  tube  follows 
and  air  no  longer  passes  to  the  ear.  To  open  the  tube  two  methods  are  employed — 
that  of  Valsalva,  and  that  of  Politzer.  The  former  consists  in  holding  the  nostrils  and 
mouth  shut  and  attempting  to  blow,  when  the  action  of  the  throat  and  palate  muscles 
opens  the  tube  and  allows  the  air  to  enter.      In  the  method  of  Politzer,  the  patient  is 

Tegmen  tympani 

Chorda  tympani  nerve 

Long  handle  of  malleus 

Tensor  tympani  muscle 


Incus 


Tympanic  membrane 


Eustachian  tube 


Fig.  104. — View  of  the  tympanic  membrane  and  ossicles  of  the  left  ear  from  within. 


given  a  sip  of  water  which  he  swallows  on  command.  The  nozzle  of  a  rubber  air-bag  is 
placed  in  one  nostril  and  the  other  held  shut.  As  the  patient  swallows,  the  air-bag  is 
compressed  and  the  air  enters  the  Eustachian  tube.  Sometimes  this  method  is  varied 
by  asking  the  patient  to  say  '  'hock, ' '  thus  causing  the  tube  to  open,  when  the  air-bag  is 
compressed.  The  calibre  of  the  tube  is  sometimes  so  small  that  probes  are  passed 
up  it  to  dilate  it.  Care  is  necessary  to  avoid  introducing  the  probe  too  far  or  it  will 
injure  the  ossicles  of  the  ear.  Pus  will  sometimes  discharge  through  the  tube.  I 
have  seen  pus  coming  from  the  middle  ear  pass  down  the  tube  into  the  inferior 
meatus  and  be  blown  out  the  anterior  nares. 

Lying  in  a  separate  canal  immediately  above  and  parallel  with  the  Eustachian 
tube  is  the  canal  for  the  tensor  tympani  muscle. 

The  attic  is  directly  above  the  tympanic  cavity  and  contains  the  greater  part  of 
the  ossicles.  Between  the  two  along  the  inner  wall  runs  a  ridge  of  bone  within  which 
is  the  aquseductus  Fallopii,  containing  the  facial  nerve.  The  roof  of  the  attic  is  called 
the  tegmen.  It  is  a  thin  shell  of  bone,  varying  in  thickness,  and  separates  the  cavity 
of  the  ear  from  the  middle  cerebral  fossa  above.  Pus  frequently  eats  its  way  through 
at  this  point  and  forms  a  subdural  abscess,  which  by  working  its  way  backw-ard 
involves  the  lateral  (transverse)  sinus,  causing  thrombosis  and  general  septic  infection. 


APPLIED   ANATOMY. 

The  antrum  is  a  little  larger  than  the  attic.  The  two  cavities  are~continuous 
through  the  aditus.  The  roof  of  the  antrum  is  level  with  the  roof  of  the  attic  and  its 
floor  is  about  level  with  the  top  of  the  membrane.  It  is  thus  seen  to  be  directly 
above  and  posterior  to  it. 

Mastoid  Cells.  — The  mastoid  cells  are  continuous  with  the  antrum  and 
permeate  the  mastoid  process  down  to  its  tip.  The  cells  come  so  close  to  the  surface 
that  suppuration  within  them  often  bursts  through  and  discharges  behind  the  ear. 
The  upper,  inner,  and  lower  portions  of  the  bone  are  also  sometimes  perforated,  which 
will  be  referred  to  later. 

Middle-ear  Disease. — Suppuration  from  middle-ear  disease  is  caused  by  an 
infective  inflammation  travelling  up  the  Eustachian  tube  from  the  pharynx  and  nasal 
cavities.  It  may  pass  to  the  attic  above  and  thence  to  the  mastoid  antrum  and 
mastoid  cells.  Pus  usually  finds  an  exit  by  perforating  the  tympanic  membrane  and 
discharging  through  the  external  auditory  meatus.  As  already  stated,  it  may  pa^s 
down  the  Eustachian  tube  to  be  blown  out  of  the  anterior  nares.  It  has  been  known 
to  pass  down  the  canal  for  the  tensor  tympani  muscle,  and  form  a  retropharyngeal 
abscess.  As  the  pus  reaches  the  pharynx  behind  the  prevertebral  fascia,  it  may 
extend  laterally  and  appear  externally  behind  the  sternomastoid  muscle.  Having 
thus  reached  the  base  of  the  skull,  the  infection  may  involve  the  meninges  and  brain 
through  the  crevices  in  the  bone.      It  is  rare  for  it  to  perforate  the  bone  below  and 


Fig.  105. — Tenotomy  of  the  tensor  tympani  tendon  Fig.  106.- 

and  separation  of  the  incus  from  the  stapes. 

Modified  from  Georges  Laurens 


Removal  of  the  incus  by  means  of  Ludwig's 
hook. 


■ 


anteriorly,  and  thus  implicate  the  jugular  vein  and  internal  carotid  artery.  It  may 
eat  into  the  posterior  wall  and  involve  the  facial  nerve,  which  is  covered  by  only  a 
thin  shell  of  bone,  and  produce  facial  paralysis,  attack  the  internal  ear  through  the 
fenestra  ovalis  and  rotunda  and  pass  through  the  internal  meatus  to  the  brain.  If  it 
extends  upward  and  involves  the  attic  and  antrum,  it  may  perforate  the  roof,  or 
tegmen,  and  form  a  subdural  abscess  in  the  back  part  of  the  middle  cerebral  fossa, 
whence  it  travels  a  distance  of  about  a  centimetre  to  the  lateral  sinus,  causing  a 
thrombus  to  form,  or  it  may  produce  an  abscess  of  the  temporosphenoidal  lobe  of 
the  brain.  The  antrum  and  mastoid  cells  being  continuous,  the  posterior  and  inner 
walls  may  be  perforated,  the  pus  thereby  reaching  the  posterior  cerebral  fossa, 
again  involving  the  lateral  sinus,  or  producing  a  cerebellar  abscess.  If  it  perforates 
the  mastoid  process  on  its  inner  wall  at  the  groove  for  the  digastric  muscle,  the  pus 
gains  access  to  the  back  of  the  neck,  forming  what  is  known  as  Bczold'  s  abscess. 

Operations  on  the  Middle  Ear. — The  operations  on  the  middle  ear,  besides 
those  involving  the  membrane,  are  done  either  for  the  removal  of  the  remains  of  the 
membrane  and  ossicles,  or  else  to  clear  out  the  antrum  and  mastoid  cells  and  e\en, 
if  necessary,  examine  the  lateral  sinus  and  jugular  vein  and  explore  the  brain.  They 
are  done  for  suppurative  affections,  which  may  be  either  chronic,  producing  local 
symptoms,  or  acute,  producing  in  addition  constitutional  disturbances  and  even 
general  infection.      Caries  of  the  bones  is  a  prominent  condition  in  suppurative  cases 


THE    EAR. 


91 


of  long  standing,  and  the  character  of  the  operation  is  dependent  on  the  extent  to 
which  the  disease  has  progressed. 

In  removal  of  the  ossicles,  the  tympanic  membrane  is  first  separated  around  its 
edges.  Then  the  tendon  of  the  tensor  tympani  muscle  is  cut,  and  the  incus  disarticu- 
lated from  the  stapes.  The  latter  is  done  by  cutting  with  a  bent  knife  across  the 
axis  of  the  stapes  and  not  of  the  incus  (see  Fig.  105).  The  malleus  is  seized  and 
drawn  first  down  and  then  out,  bringing  the  membrane  with  it,  and  afterwards  the 
incus,  which  is  detached  by  Ludwig's  hook  (see  Fig.  106),  is  removed,  and,  if 
desired,  the  stapes.  Granulations  and  pus  are  removed  by  the  snare,  forceps  or 
curette.  Care  is  to  be  taken  to  avoid,  if  possible,  scraping  away  the  thin  shell  of 
bone  on  the  internal  wall  that  covers  the  facial  nerve.  Any  twitching  of  the 
muscles  of  the  face  indicates  that  the  nerve  is  being  irritated.  The  chorda 
tympani  nerve,  which  passes  on  the  inner  side  of  the  handle  of  the  malleus  and  lies 
beneath  the  mucous  membrane,  is  of  necessity  removed.  No  important  symptoms 
follow  its  removal. 

Operations  on  the  Antrum  and  Mastoid  Cells. — In  order  to  understand 
these  operations,  one  must  recall  that  the  suprameatal  crest  is  the  ridge  of  bone  forming 
the  upper  edge  of  the  bony  meatus,  and  a  continuation  backward  of  the  posterior  root 


Suprameatal  tri- 
angle of  Macewen 


Suprameatal  spine 


Posterior  root  of  zygoma 


Fig.  107. — Landmarks  for  operating  to  enter  the  mastoid  antrum. 

of  the  zygoma.  The  upper  and  posterior  edge  of  the  meatus  is  formed  by  a  thin,  small 
shell  or  edge  of  bone  running  from  the  suprameatal  crest  downward  and  backward 
to  the  posterior  wall;  this  is  the  suprameatal  spine.  Behind  the  suprameatal  spine 
and  between  it  and  the  posterior  portion  of  the  suprameatal  crest  is  a  depression, 
the  suprameatal  fossa.  This  suprameatal  fossa  is  triangular  in  shape.  The  crest 
forms  the  upper  side,  the  spine  its  anterior  side,  and  the  ridge  of  bone,  running  from 
the  posterior  portion  of  the  crest  to  the  lower  portion  of  the  spine,  forms  the  posterior 
side.  These  three  lines  form  the  suprameatal  triangle  of  Macewen.  It  is  through 
this  triangle  that  the  antrum  may  be  reached.  The  operation  may  be  restricted  to  the 
antrum  and  tympanic  cavity,  or  may  include  the  whole  or  part  of  the  mastoid  cells, 
constituting  the  operation  known  as  tympanomastoid  exenteration. 

To  reach  the  antrum  a  semicircular  cut  is  made  a  centimetre  back  of  the  ear 
and  the  ear  and  membranous  canal  loosened  and  pushed  forward.  With  a  gouge 
chips  of  bone  are  removed  from  the  suprameatal  spine  backward  and  from  the  crest 
downward  as  far  as  desired.  This  will  extend  considerably  beyond  the  line  marking 
the  posterior  boundary  of  Macewen' s  triangle.  The  outer  table  of  bone  being 
removed,  the  cells  are  broken  through  parallel  to  the  meatus  and  slightly  upward, 


92 


APPLIED    ANATOMY. 


for  the  lower  level  of  the  antrum  corresponds  to  the  upper  edge  of  the  meatus. 
It  is  hardly  safe  to  penetrate  deeper  than  1.5  cm.  (fin.)  from  the  meatal  spine 
inward,  for  fear  of  wounding  the  facial  nerve.  The  mastoid  antrum  lies  not  only 
above  and  posterior  to  the  membrane  and  tympanic  cavity,  but  extends  outward 
along  the   posterior  and   upper  portion   of  the  canal,  and  the   facial  nerve  can  be 


Mastoid  antrum 

External  auditory  meatus 


Fig.  ioS.- 


Mastoid  cells 


-The  mastoid  antrum  exposed  by  chiselling  through  the  suprameatal  triangle.    The  mastoid  cells  exposed 
by  chiselling  off  the  surface  of  ihe  mastoid  process. 


wounded  only  by  passing  across  the  antrum  and  attacking  the  bony  covering  of  the 
Fallopian  canal  below  and  anteriorly. 

In  doing  a  tympanomastoid  exenteration,  a  more  extensive  procedure  is 
performed.  It  consists  in  cleaning  out  the  various  communicating  cavities  and 
throwing  them  together,  thus  making  their  interior  more  accessible.      The  antrum  is 

reached  in  one  of  two  ways :  either 
posteriorly,  or  anteriorly  through 
the  meatus.  The  posterior  opera- 
tion, or  that  of  Schwartze,  Zaufal, 
and  others,  consists  in  removing 
the  membranous  lining  of  the  bony 
meatus  on  its  upper  and  posterior 
portions  down  to  the  tympanic 
membrane.  The  antrum  is  then 
entered  as  already  described;  the 
posterior  bony  wall  of  the  meatus 
is  chiselled  away,  giving  access  to 
the  tympanum;  the  ridge  of  bone 
separating  the  roof  of  the  bony 
meatus  from  the  attic  or  epitym- 
panum  is  chiselled  away  (see  Fig. 
109),  and  the  membrane  and  os- 
sicles removed.  This  gives  access 
to  the  tympanic  cavity,  epitym- 
panum,  and  antrum.  As  much  of 
the  mastoid  cells  as  necessary  is 
exposed  by  chiselling  away  their  external  covering  of  bone  even  down  to  the  tip  of 
the  mastoid  process. 

If  the  anterior  operation  of  Stacke  is  performed,  the  membranous  lining  of  the 
bony  meatus  is  to  be  loosened  and  divided  as  close  to  the  membrane  as  possible  and 
drawn  forward  with  the  cartilaginous  meatus.  The  drum  membrane  and  as  much  of 
the  ossicles  as  possible  are  then  to  be  removed,  and  with  a  chisel  or  bent  gouge  the 


Fig.  109. — Chiselling  away  the  spur  of  bone  between  the  roof  of  the 
external  auditory  meatus  and  attic  or  epitympanum. 


THE   EAR. 


93 


angle,  or  ridge  of  bone  between  the  upper  side  of  the  bony  meatus  and  epitympanum, 
or  attic,  cut  away.  The  antrum  is  now  entered  by  chiselHng  away  the  upper  posterior 
wall  and  the  chiselling  away  of  bone  continued  until  the  mastoid  cells  have  been  suffi- 
ciently exposed.      The  final  result  of  these  two  methods  is  the  same.      The  external 


Course  of  lateral 
(transverse)  sinus 


Position 
mastoid  antrum 


Suprameatal  spine 


Anterior  root  of 
zygoma  or  emi- 
nentia  articularis 


Posterior  root 
of  zygoma 


Mastoid  process 


External  auditory  meatus 


Fig.  1 10. — Lateral  view  of  the  temporal  bone,  showing  the  relations  of  the  lateral  or  transverse  sinus  and 

mastoid  antrum. 


rneatus,  tympanum,  epitympanum,  antrum,  and  mastoid  cells  are  all  thrown  into  one 
large  cavity.  Wounding  of  the  facial  nerve  is  to  be  avoided  by  first  learning  its  course 
and  then  by  sponging  away  the  blood  and  cutting  only  the  structures  which  are 
clearly  visible.  Tracing  the  facial  nerve  backward,  it  is  seen  (Fig.  103)  entering 
the  stylomastoid  foramen, 
passing  upward  posterior 
to  the  tympanic  cavity, 
and  crossing  at  about  its 
upper  edge  to  pass  above 
the  oval  window.  Viewed 
in  Fig.  101,  it  is  seen  that 
the  Fallopian  canal  lies  a 
trifle  nearer  to  the  external 
surface  than  does  the  tym- 
panic membrane,  so  that 
in  making  the  opening  into 
the  antrum  or  in  connect- 
ing the  mastoid  cells  below 
the  antrum  with  the  tym- 
panic cavity,  care  should 
be  taken  to  keep  a  little 
anterior  or  superficial  to 
the  membrane. 

Relations  of  the 
Brain  and  Lateral  Si- 
nus.— In  operating  on  the 
skull  for  middle-ear  dis- 
ease, it  is  desirable  to  know- 
how  to  reach  and  how  to  avoid  the  brain  and  lateral  sinus.  The  lower  level  of  the 
brain  in  the  region  of  the  ear  corresponds  to  a  prolongation  directly  backward  in  a 
straight  line  of  the  posterior  root  of  the  zygoma.  If  one  keeps  below  this  line,  he  is 
not  likely  to  open  the  brain  case.     If  it  is  desired  to  explore  the  under  surface  of  the 


Fig. 


Jugular  foramen 


III.— Transverse  section  of  the  right  side  of  the  skull  just  behind  the 
mastoid  process  ;  looking  forward. 


94  APPLIED    ANATOMY. 

brain  or  dura  directly  over  the  middle-ear  cavity,  then  one  trephines  above  this  line 
or  suprameatal  crest,  the  lower  edge  of  the  trephine  opening-  being  .5  cm,  above  it. 
This  will  lead  to  the  middle  fossa  of  the  skull,  occupied  by  the  temporosphenoidal 
lobe.  The  sharp  upper  and  posterior  edge  of  the  petrous  portion  of  the  temporal 
bone  gives  attachment  to  the  tentorium  and  separates  the  middle  cerebral  fossa  in 
front  from  the  posterior  fossa,  containing  the  cerebellum,  behind.  The  point  at  which 
this  ridge  and  tentorium  reach  the  side  of  the  skull  is  indicated  by  the  point  of  cross- 
ing of  a  line  drawn  up  from  the  tip  of  the  mastoid  process,  midway  between  its  anterior 
and  posterior  borders,  and  the  line  of  the  posterior  root  of  the  zygoma.  The  course 
of  the  lateral  sinus  is  indicated  by  a  curved  line  from  above  and  to  the  right  (about 
.5  to  I  cm.)  of  the  external  occipital  protuberance  to  the  upper  posterior  portion  of 
the  mastoid  process  and  thence  to  its  tip.  The  anterior  edge  of  the  lateral  sinus 
reaches  as  far  forward  as  a  line  drawn  from  the  tip  of  the  mastoid  upward,  midway 
between  its  anterior  and  posterior  borders.  The  point  at  which  it  turns  is  where  this 
mastoid  line  intersects  the  line  of  the  zygoma.  Its  upper  edge  rises  above  this  line 
approximately  i  cm.  The  sinus  is  I  cm.  in  width.  The  distance  of  the  sinus  from 
the  surface  varies  from  .5  cm.,  or  even  less,  at  the  top  of  the  mastoid  process  to  1.5 
cm.  at  its  tip.  So  uncertain  is  this  that  the  only  safe  way  to  expose  the  sinus  is  to 
cut  the  bone  of?  with  a  mallet  and  gouge  in  thin  chips  parallel  to  the  surface.  The 
use  of  a  trephine  or  other  boring  instrument  is  not  to  be  advised.  If  the  infection 
of  the  lateral  sinus  has  extended  to  the  jugular  vein  this  latter  must  be  reached  by 
means  of  a  separate  incision  in  the  neck. 

THE    NOSE. 

Externally  the  nose  forms  a  prbminent  projection  on  the  face,  hence  it  is  fre- 
quently injured  and  its  construction  should  be  studied  in  relation  to  those  injuries. 
It  forms  a  conspicuous  portion  of  the  features,  hence  deformities  or  disfigurements  of 
it  are  very  distressing,  so  that  plastic  operations  are  done  for  their  relief.  Internally, 
the  nasal  cavities  are  concerned  in  the  sense  of  smell  and  form  the  passage-way  to 
and  from  the  lungs  and  the  various  accessory  cavities  for  the  air  in  respiration.  It 
likewise  serves  as  a  receptacle  for  the  tears  as  they  come  down  the  lachrymona^al 
duct.  Interference  with  the  flow  of  air  by  obstruction  of  the  nasal  chambers  may 
cause  affections  of  the  pharynx,  larynx,  lungs,  ears,  or  accessory  sinuses — ethmoid, 
sphenoid,  maxillary,  and  frontal.  Catarrhal  troubles  may  start  in  the  nose  and  invade 
any  of  these  parts.  They  may  even  extend  up  the  Eustachian  tube  and  cause  deaf- 
ness; or  up  the  lachrymonasal  duct  and  cause  trouble  with  the  lachrymal  canal  or 
conjunctiva.  A  knowledge  of  the  nose  is  essential  to  all  those  who  wish  to  devote 
themselves  especially  to  affections  of  the  eye,  ear,  and  throat,  because  the  origin  of 
the  affections  of  these  organs  may  be  in  the  nasal  chambers  instead  of  the  organ  in 
which  they  are  most  manifest. 

The  skin  over  the  root  of  the  nose  is  thin  and  lax.  It  is  well  supplied  with 
blood  by  the  frontal  and  nasal  branches  of  the  ophthalmic,  and  the  angular  branch 
of  the  facial  arteries.  In  reconstructing  a  nose  by  means  of  a  flap  taken  from  the 
forehead,  it  is  these  branches  that  nourish  it.  The  laxity  of  the  skin  allows  the 
pedicle  to  be  twisted  around  without  interfering  with  the  circulation. 

The  skin  over  the  tip  and  alae  is  thick  and  adherent  to  the  cartilages.  It  pos- 
sesses a  comparatively  scanty  blood  supply,  hence  its  liability  to  suffer  from  cold,  and 
is  a  favorite  site  for  ulcerations,  as  lupus,  superficial  epithelioma  (rodent  ulcer),  etc. 
Sebaceous  and  sweat  glands  are  abundant,  and  stiff  hairs  guard  the  inside  of  the  nos- 
trils. These  latter  are  not  seldom  the  seat  of  small  furuncles  or  boils,  which  are 
extremely  painful.  This  is  due  to  the  tension  caused  by  the  congestion  and  swelling, 
which  is  restricted  by  the  tissues  being  so  firmly  bound  to  the  cartilages  beneath. 

Nerves. — In  addition  to  the  olfactory  nerve,  the  nose  is  supplied  by  the  nasal, 
infratrochlear,  and  infra-orbital  branches  of  the  fifth  nerve,  hence  the  eyes  water 
when  the  nose  is  injured.  In  certain  cases  of  neuralgia  affecting  the  ophthalmic 
division  of  the  fifth  nerve,  pain  is  felt  along  the  side  of  the  nose.  As  the  nasal 
nerve  enters  the  skull  from  the  orbit  through  the  anterior  ethmoidal  foramen,  it  may 
be  involved  in  disease  of  the  ethmoidal  sinuses. 


THE   NOSE. 


95 


the 
the 


I 


Small  alar  , 
cartilage 


Lower  lateral 
cartilage 


Nasal  bone 


Septal 
'cartilage 


The  nose  proper  consists  of  a  bony  and  a  cartilaginous  portion.    The  bony portioyi 
is  formed  by  the  two  nasal  bones  articulating  with  the  frontal  bone  above,  with  each 
other  in  the  median  line,  and  with   the  nasal  process  of  the  superior  maxilla  on 
side.      They   are    supported    on  the  inside   by  the   upper  anterior  portion    of 
perpendicular  plate  of  the  ethmoid. 

This  articulation  does  not  extend  n 

the  whole  length  of  the  nasal  bones 
to  their  tip,  but  only  about  half 
their  length. 

The  cartilaginous  portion 
consists  of  four  lateral  cartilages, 
two  on  each  side,  upper  and  lower, 
and  the  triangular  cartilage,  or  car- 
tilaginous septum  on  the  inside. 

The  external  shape  of  the  nose 
viewed  in  profile  is  composed  of 
three  portions:  an  upper  of  bone, 
a  middle  of  cartilage — the  upper 
lateral  cartilages — and  a  lower,  or 
tip,  formed  by  the  lower  lateral  car- 
tilages. The  bridge  of  the  nose  is 
formed  by  bone;  it  slopes  down- 
ward and  forward  and  where  it  joins 
the  upper  lateral  cartilage  the  line 
changes  and  slopes  more  downward,  until  the  tip  is  reached,  here  the  lower  lateral 
cartilages  bulge  forward,  forming  a  rounded  and  more  or  less  projecting  tip. 

Injuries  to  the  Nose. — The  bones  and  cartilages  may  be  fractured  or 
dislocated.  This  may  involve  either  the  outside  structures  or  those  forming  the 
septum,  and  often  both.      The  displacement  depends  on  the  character  and  direction 


Mesial  crus  of 
lower  lateral 
cartilage 


-Bony  and  cartilaginous  framework  of  nose,  front 
aspect.     (Piersol.) 


Fig.  113 — Fracture  of  the  nose  with  deflection  of  the  nasa!  bone  laterally. 

of  the  injury.  It  is  either  a  displacement  to  one  side,  or  the  nose  is  crushed, 
producing  a  flattening  of  the  bridge.  If  the  displacement  is  lateral,  whether  by  a 
dislocation  or  fracture,  there  is  liable  to  be  a  deviation  of  the  septum,  because  the 
bony  and  cartilaginous  septum  is  connected  with  the  bones  and  is  apt  to  be  carried 
with  them  to  the  side.  If  the  displacement:  is  inward,  not  only  are  the  nasal  bones 
depressed,  but  the  septum  beneath  may  be  either  bent  or  fractured.  The  pushing 
of  the  septum  toward  the  floor  causes  it  tc  buckle  and  bend  or  even  break  at  the 


96  APPLIED    ANATOMY. 

junction  of  the  triangular  cartilage  with  the  perpendicular  plate  of  the  ethmoid  and 
the  vomer.  In  treating  these  fractures,  the  most  efficient  method  is  to  grasp  the 
septum  with  the  flat  blades  of  an  Adams  forceps  (after  cocainization;  and  lift 
the  bones  up  or  to  one  side  as  needed.  In  cases  where  it  is  not  desired  to  use 
the  forceps,  the  writer  grasps  the  nose  with  a  wet  towel,  makes  traction  to  loosen 
the  fragments,  and  then  pushes  them  over  into  place.  The  triangular  cartilage  is 
frequently  injured;  with  the  displacement  or  loosening  of  the  upper  lateral  cartilages 
a  great  amount  of  displacement  may  be  caused,  so  that  the  nose  instead  of  forming  a 
straight  line  is  bent  to  one  side  from  the  ends  of  the  bones  down  to  the  tip.  Injuries 
to  the  septum  in  childhood  are  probably  the  cause  of  a  large  number  of  the  cases  of 
deviation  of  the  septum,  spurs,  etc.,  seen  later  in  life. 

In  fractures  the  mucous  membrane  is  often  torn,  thus  allowing  air  to  enter  the 
tissues  at  the  site  of  fracture,  producing  emphysema.  If  such  a  patient  blows  the 
nose  violently,  the  air  may  be  forced  under  the  skin  of  the  face,  around  the  eyes  and 
up  the  forehead. 

Anterior  Nares. — The  nostrils  or  anterior  nares  in  the  white  race  are  an 
elongated  oval  in  shape  and  run  in  an  anteroposterior  direction,  being  separated  from 
each  other  by  the  columna.     They  lie  in  a  direction  parallel  with  the  floor  of  the  nose. 


Fig.  114 — Fracture  of  the  nose  showing  depression  of  the  nasal  bone. 

so  that  to  examine  the  nasal  fossae  with  a  speculum  the  instrument  is  first  introduced 
from  below,  then  tilting  the  tip  of  the  nose  upward,  the  speculum  is  directed  back- 
ward. To  see  the  floor  of  the  nose,  it  is  necessary  to  raise  the  outer  end  of  the 
speculum  still  higher,  because  the  floor  is  below  the  bony  edge.  From  the  outer 
edge  of  the  nostril  the  nasal  cavities  go  upward  and  backward  for  a  distance  of  .5  to 
I  cm.  This  part,  called  the  vestibule,  is  covered  by  skin,  not  mucous  membrane. 
It  bears  stiff  hairs — vibrissae.  Inflammation  of  these  hair-follicles  and  associated 
glands  produces  exceedingly  painful  pustules.  It  is  here  likewise  that  dried  mucus 
collects  and  forms  scabs,  which  stick  to  the  hairs  and  are  hard  to  remove.  The 
attempt  to  remove  them  probably  is  the  cause  of  infection  and  inflammation  around 
the  roots  of  the  hairs.  The  vestibule  leads  to  the  ridge  of  bone  or  crest,  which  is 
directly  posterior  to  the  side  of  the  nasal  spine.  This  ridge  of  bone  is  on  a  higher 
level  than  the  floor  of  the  nose,  and  in  order  to  view  the  latter  the  nostrils  must  be 
raised,  by  means  of  the  speculum,  above  it  (Fig.  115). 

View  from  the  Anterior  Nares. — In  looking  into  the  nose  from  in  front,  if  the 
speculum  is  directed  downward,  the  floor  of  the  nose  and  the  inferior  meatus  can 
be  seen.      On  the  inner  side  is  the  septum,   on  the  outer  the  anterior  end  of  the 


THE    NOSE. 


97 


Vestibul 


Fig.  115. — Lateral  view  of  the  interior  of  the  nose. 


inferior  turbinated  bone.  Still  higher  is  the  middle  meatus  and  the  anterior  end  of  the 
middle  turbinated  bone.  The  superior  turbinated  bone  is  not  visible  from  the  front, 
being  in  the  upper  posterior  corner  and  hidden  from  sight  by  the  middle  turbinated. 
Sometimes  in  the  upper  portion  of 
the  nose,  beneath  the  outer  surface 
of  the  anterior  extremity  of  the  mid- 
dle turbinated  bone,  is  seen  a  small 
cleft,  the  hiatus  semilunaris,  leading 
through  the  infundibulum  into  the 
frontal  sinus.  If  the  inferior  turbi- 
nated has  been  shrunk  with  cocaine, 
and  if  the  inferior  meatus  is  roomy, 
one  can  see  the  posterior  wall  of  the 
pharynx.  This  can  be  seen  moving 
if  the  patient  swallows,  pronounces 
the  letter  "k,"  etc.,  (Fig.  116). 

Septum. — The  nasal  fosses  are 
separated  from  each  other  by  the  sep- 
tum. This  septum  is  formed  (see 
Fig.  117)  by  the  triangular  cartilage 
in  front,  forming  the  cartilagifious  sep- 
tum, and  the  perpendicular  plate  of 
the  ethmoid  and  vomer  behind,  form- 
ing the  bony  septum.  The  posterior 
edge  of  the  septum  is  formed  solely 
by  the  edge  of  the  vomer ;  it  can  readily  be  seen  with  the  rhinoscopic  mirror.  The 
affections  of  the  septum  are  haematoma,  ulcer  and  abscess,  deviation  to  one  side, 
spurs  or  outgrowths,  and  it  may  be  the  site  of  nasal  hemorrhages.     Hcematomas  affect 

the  cartilage  of  the  septum  and  resemble 
those  of  the  ear.  They  are  usually  due 
to  traumatism  and  may  become  infected, 
forming  a  pus-like  detritus  or  abscess. 
They  can  readily  be  recognized  as  a 
fluctuating  swelling  on  the  septum,  one 
or  both  sides  being  affected. 

Deviations  of  the  septum  are  bend- 
ings  toward  one  side,  and  cause  serious 
obstruction  to  breathing.  They  are  prob- 
ably traumatic  in  origin  and  involve  the 
cartilaginous  portion.  In  operating  for 
their  correction,  incisions  are  made 
through  the  cartilage  and  the  projecting 
part  pushed  toward  the  median  line.  In 
some  operations  care  is  taken  not  to  cut 
through  the  mucous  membrane  on  both 
sides,  as  well  as  through  the  cartilage. 
This  is  done  to  avoid  the  formation  of 
a  permanent  perforation  of  the  septum, 
the  presence  of  which  may  cause  a  very 
objectionable  whistling  sound  when  the 
patient  breathes.  As  the  mucous  mem- 
brane covering  the  cartilage  is  thin,  great 
care  is  necessary  in  dividing  the  cartilage 
to  avoid  wounding  the  side  which  it  is  de- 
sired to  leave  intact.  The  triangular  cartilage  is  thin  at  its  centre  and  thick  at  its  edges. 
Spurs  are  usually  outgrowths  of  bone  or  cartilage  occurring  in  the  line  of 
juncture  of  the  cartilage  and  vomer.  On  the  floor  of  the  nose  the  nasal  crest  may 
project  quite  perceptibly  to  one  side;  a  cartilaginous  projection  may  likewise  occupy 
this  site.  As  these  spurs  are  found  on  the  anterior  edge  of  the  vomer,  they  some- 
7 


Fig,  116. — Examining  the  anterior  nares.     Middle 
and  inferior  turbinates  exposed  to  view. 


98 


APPLIED     ANATOMY. 


times  form  a  distinct  ridge  of  bone  running  upward  and  backward.  If  the  spur  is 
short  in  extent,  the  farther  posterior  it  is  situated,  the  higher  up  it  is  on  the  septum. 
If  marked,  it  is  often  accompanied  by  deviation  of  the  septum  and  it  may  impinge 
on  the  lower  turbinated  bone  opposite  to  it.  These  spurs  are  usually  removed  by 
sawing.  A  narrow-bladed  saw  is  introduced  with  its  back  on  the  floor  of  the  nose 
and  the  spur  removed  by  sawing  upward  (Fig.  ii8). 

Epistaxis  or  bleeding  from  the  nose  is  said  to  occur  in  a  large  percentage  of 
the  cases  from  the  septal  branch  of  the  sphenopalatine  artery.  This  comes  from  the 
internal  maxillary  artery  through  the  sphenopalatine  foramen  and  passes  downward 
and  forward  as  the  nasopalatine  or  artery  of  the  septum.  It  anastomoses  below  with 
the  anterior  palatine  branch  of  the  descending  palatine  artery  as  it  comes  up  from 
the  roof  of  the  mouth  through  \.\\e  foramen  of  Stenson  (incisor  foramen).  It  also 
anastomoses  with  the  inferior  artery  of  the  septum,  a  branch  of  the  superior  coronary. 
The  bleeding  point  is  to  be  sought  for  low  down  on  the  anterior  portion  of  the 
cartilaginous  septum  near  the  anterior  nares.  Hemorrhage  can  be  stopped  by 
packing  only  the  anterior  or  both  the  anterior  and  posterior  nares. 


Perpendicular  plate 
of  ethmoid 


Triangular  cartilage 


Vomer 


Fig.  117. — Septum  of  the  nose. 

The  arteries  supplying  the  nasal  cavities  (Fig.  119;  come  from  three  directions  : 
superior — the  anterior  and  posterior  ethmoidal,  supplying  the  ethmoidal  cells,  the 
upper  portion  of  the  septum,  the  roof,  and  the  outer  wall  anteriorly;  inferior — the  septal 
branch  of  the  superior  coronary  artery  and  a  branch  of  the  descending  palatine  artery 
coming  up  through  the  incisor  foramen;  posterior — the  sphenopalatine,  giving  its 
nasopalatine  branch  to  the  septum  and  also  supplying  branches  to  the  ethmoidal 
cells,  frontal  and  maxillary  sinuses,  and  outer  wall  of  nose,  the  Vidian  and  pterygo- 
palatine going  to  the  posterior  portion  of  the  roof,  and  the  desce^iding  palatine  giving 
branches  to  the  posterior  portion  of  the  inferior  meatus  and  posterior  end  of  the 
inferior  turbinated  bone. 

The  veins,  like  the  arteries,  are  in  three  sets:  the  superior  are  formed  by  the 
anterior  and  posterior  ethmoidal  and  some  smaller  veins  passing  upward  through  the 
foramen  in  the  cribriform  plate,  ox  foramen  ccsczim,  to  the  longitudinal  sinus;  the 
inferior  communicate  with  the  facial  veins  through  the  anterior  nares;  the  posterior 
drain  upward  and  backward  through  the  sphenopalatine  foramen  into  the  pterygoid 
plexus. 

The  lymphatics  drain  either  anteriorly  on  the  face  or  posteriorly  through  the 
deep  lymphatics  of  the  neck.  Therefore,  acrid  secretions  causing  ulcerations  of  the 
anterior  nares  are  liable  to  be  accompanied  by  swelling  of  the  submaxillary  lymphatic 


THE    NOSE. 


99 


nodes;    while  enlargement  of   the  deep  cervical  lymphatics  follows  disease  of    the 
deeper  nasal  cavities. 

Nasal  hvpertrophies  are  enlargements  of  the  nasal  mucous  membrane.  The 
mucous  membrane  of  the  nose  or  Schneiderian  membrane  has  columnar  ciliated  cells 
on  its  surface  and  mucous  cells  beneath.  It  is  prolonged  into  the  various  sinuses  and 
cavities  in  connection  with  the  nasal  fossae.  The  membrane  on  the  upper  third  of 
the  septum,  the  upper  portion  of  the  middle  turbinated,  and  the  superior  turbinated 
bone,  contains  the  terminal  filaments  of  the  olfactory  nerve.  The  membrane  over 
the  lower  portion  of  the  septum,  over  the  lower  edge  of  the  middle,  and  the  greater 
part  of  the  inferior  turbinated  bones,  contains  a  venous  plexus  which  renders  it 
erectile.  On  the  slightest  irritation  this  portion  of  the  membrane  will  swell  and 
obstruct  the  passage  of  air  through  the  nostrils.  Repeated  swelling  of  the  membrane 
of  the  septum  produces  thickenings  of  the  septum,  which  if  anterior  may  be  seen 
through  the  nostrils,  and  if  posterior  by  the  rhinoscopic  mirror.      The  membrane 


Spur 


Nasal  crest 


over  the  inferior  turbinated  bones  also  becomes  swollen  and  enlarged,  constituting,  if 
at  the  forward  end,  anterior  hypertrophy,  and  if  at  the  posterior  extremity,  posterior 
hypertrophy  CFig.  120).  They  can  be  readily  seen  through  the  nasal  speculum  ante- 
riorly and  by  the  rhinoscopic  mirror  posteriorly.  They  are  treated  by  applications  of 
acids,  as  chromic  and  trichloracetic,  by  the  electrocautery,  or  are  snared  of!  with  the 
cold  snare.  Snaring  is  more  often  employed  in  reducing  posterior  hypertrophies,  but 
both  the  anterior  and  posterior  can  be  reached  by  an  electrocautery  point  or  a  knife 
introduced  through  a  speculum  in  the  anterior  nares. 

The  Outer  Wall. — The  outer  wall  has  on  it  the  three  turbinated  bones — 
superior,  middle,  and  inferior.  The  inferior  is  a  separate  bone,  but  the  middle  and 
superior  are  parts  of  the  ethmoid  bone  (Figs.  121  and  122). 

The  inferior  meatus  is  between  the  inferior  turbinated  bone  and  the  floor  of 
the  nose.  The  lachrymonasal  duct  enters  this  meatus  just  below  the  anterior  end 
of  the  inferior  turbinated  bone.  It  j^erces  the  mucous  membrane  obliquely,  being 
guarded  by  a  fold  called  the  valve  of  Hasner.  The  opening  is  not  visible  from  the 
anterior  nares  and  usually  it  is  impossible  to  introduce  a  probe  into  it  from  them. 


lOO 


APPLIED    ANATOMY. 


The  middle  meatus  is  between  the  middle  and  inferior  turbinated  bones. 
The  mucous  membrane  covering  the  middle  turbinated  bone  lies  closer  to  it  than 
does  that  of  the  inferior  turbinated  bone,  so  that  it  is  comparatively  rare  that  treat- 
ment is  necessary  to  reduce  it. 

Polypi  usually  have  their  origin  in  this  meatus.  Beneath  the  middle  turbinated 
bone  on  the  outer  wall  of  the  nose  and  only  to  be  seen  after  removal  of  the  bone, 


Anterior  ethmoidal 


Posterior  ethmoidal 


•Triangular  cartilage — 


Septal  branch  of 
superior  coronary 


Branch  from  the  descending  palatine 
Fig.  1 1 9. — .\rteries  supplying  the  septum  of  the  nose. 

there  is,  just  anterior  to  its  middle,  a  rounded  eminence,  the  bulla  etlunoidalis.  In  it 
is  an  opening  for  the  middle  ethmoidal  cells.  Immediately  in  front  is  a  slit,  the 
hiatus  semihoiaris,  into  which  open  the  maxillary  sinus  {antrum  of  Highmore)  and 
the  anterior  ethmoidal  cells.  The  hiatus  is  continued  above  as  the  infundibuhim, 
which  enters  the  frontal  sinus.     The  relation  between  the  hiatus  and  the  opening  into 


Anterior  nasal  hypertrophy 


Posterior  nasal  hypertrophy 
Fig.  120. — View  of  anterior  and  posterior  hypertrophies  of  the  inferior  turbinate. 

the  maxillary  sinus  is  such,  in  some  cases,  that  it  is  possible  for  pus  originating  in 
the  frontal  sinus  to  discharge  into  the  maxillary  sinus.  A  knowledge  of  the  relation 
of  these  parts  is  essential  to  those  desirous  of  treating  nasal  diseases. 

The  superior  meatus  is  comparatively  small  and  lies  above  the  middle  tur- 
binated bone.  At  the  anterior  edge  of  the  superior  turbinated  bone  is  the  opening 
tor  the  posterior  ethmoidal  cells.     Sometimes  there  are  two  or  three  superior  turbinals. 


THE    NOSE. 


The  spheno -ethmoidal  XQ.CQS%  is  the  cleft  above  the  superior  turbinated  bone;  into 
it  opens  the  sphenoidal  sinus.  In  order  to  examine  and  reach  the  openings  of  any 
of  these  sinuses,  it  is  practically  necessary  to  take  away  a  part  or  all  of  the  middle 
turbinated  bone  before  they  can  be  exposed  to  view.  When  this  is  done,  they  can 
be  probed,  washed  out,  drained,  etc.  (see  Fig.  125). 

The  frontal  sinuses  begin  to  develop  about  puberty.  They  occupy  the  lower 
anterior  portion  of  the  frontal  bone.  Their  size  and  extent  vary  considerably.  The 
usual  size  is  from  the  nasion  below  to 
the  upper  edge  of  the  superciliary  ridges 
above  and  laterally  from  the  median  line 
to  the  supra-orbital  notch.  These  limits 
may  be  exceeded  considerably.  They 
may  go  as  far  out  as  the  middle  of  the 
upper  edge  of  the  orbit  or  even  nearly 
to  the  temporal  ridge.  The  anterior  and 
posterior  walls  are  separated  a  distance 
of  0.5  to  I  cm.  The  distance  which  they 
extend  back  over  th-e  orbit  and  upward 
also  varies.  The  two  sinuses  are  sepa- 
rated by  a  partition  which  is  often  to  one 
side  of  the  median  line,  so  that  it  is  apt 
to  be  encountered  in  opening  the  sinus 
through  the  forehead.  The  two  cells 
often  differ  greatly  in  size  and  may  be 
divided  into  various  recesses  by  incom- 
plete septa.  They  have  the  infundib- 
ulum  as  their  lower  extremity,  which 
passes  into  the  hiatus  semilunaris  be- 
neath the  middle  turbinated  bone  and  empties  into  the  middle  meatus.  The  frontal 
sinuses  are  frequently  the  seat  of  suppurative  inflammation.  This  gives  rise  to 
pain  and  tenderness  in  the  supra-orbital  region  and  to  a  discharge  from  the  cor- 
responding nostril.  This  discharge  can  be  seen  coming  from  beneath  the  anterior 
extremity  of  the  middle  turbinated  bone.  Owing  to  the  proximity  of  the  opening 
into  the  maxillary  sinus,  pus,  coming  down  the  hiatus  from  the  frontal  sinus,  may 


Fig.  121. 


Outer  wall  of  nose,  showing  the  superior,  mid- 
dle, and  inferior  turbinate  bones. 


Probe  in  the  lachrymo- 
nasal  duct 


Hiatus  semilunaris 


Opening  of  lachrymo- 
nasal  duct 


Frontal  sinus 

Anterior  ethmoidal  cell 
Middle  ethmoidal  cells 

Posterior  ethmoidal  cells 

Sphenoidal  sinus 

Bulla  ethmoidalis 
Superior  turbinate 
Middle  turbinate  (anterior 
half  removed) 


Opening  into  Inferior  turbinate 

maxillary  sinus 

Fig.  122. — View  of  outer  wall  of  the  nose  and  accessory  cavities. 

pass  mto  the  maxillary  sinus,  thus  simulating  disease  of  that  cavity.  In  order  to 
wash  out  the  sinus,  cocaine  may  be  first  applied  to  shrink  the  nasal  membrane  ;  then 
sometimes  one  is  able  to  pass  a  probe  or  irrigating  tube  into  the  hiatus  semilunaris 
and  thence  up  into  the  sinus.  By  removing  the  anterior  extremity  of  the  middle 
turbinated  bone  access  to  the  hiatus  semilunaris  is  more  readily  obtained.  In  cer- 
tain cases  the  frontal  sinus  is  opened  either  through  the  supra-orbital  region  or 
entered  through  the  roof  of  the  orbit  at  its  inner  upper  corner.     The  glabella  is  the 


I02  APPLIED    ANATOMY. 

depression  in  ttie  median  line  separating  the  superciliary  ridges.  In  operating  on 
the  sinus  from  in  front,  the  opening  is  to  be  made  just  to  the  outer  side  of  the  gla- 
bella in  order  to  avoid  the  septum  between  the  sinuses.  In  curetting  the  sinus,  the 
thinness  of  the  upper  and  posterior  wall  separating  it  from  the  brain,  and  of  the 
lower  wall  or  roof  of  the  orbit,  should  be  borne  in  mind,  otherwise  they  are  apt  to  be 
perforated.     The  sinus  may  be  divided  into  recesses  by  partial  septa  projecting  from 


Figs.  123  and   124. — Two  views  of  the  frontal   sinus,   showing  variation  in  size  in  different  individuals.     The 
anterior  wall  has  been  cut  away  to  expose  the  interior  of  the  sinus. 

the  sides.  Drainage  into  the  nose  is  obtained  by  passing  an  instrument  from  above 
downward  through  the  anterior  ethmoidal  cells.  In  entering  the  sinus  from  below 
from  the  outside,  the  opening  is  made  at  the  extreme  anterior  upper  edge  of  the 
orbit,  perforating  the  bone  in  a  direction  upward  and  inward.  The  opening  into  the 
sinus  may  be  enlarged  from  within  the  nose  by  first  inserting  a  probe  to  protect  the 

brain  and  posterior  wall  and  then  chisel- 
ling or  gnawing  away  the  bone  in  front 
so  that  easy  access  is  obtained  through 
the  nose  for  drainage,  packing,  etc. 

The  ethmoidal  sinuses  or  cells, 
three  in  number  on  each  side,  anterior, 
middle,  and  posterior,  lie  between  the 
sphenoidal  sinus  posteriorly,  and  the 
lower  extremity  of  the  frontal  sinus  an- 
teriorly. The  anterior  cells  lie  in  front 
of  or  just  above  the  hiatus  and  open 
into  it.  The  middle  lie  just  posterior  to 
the  hiatus  and  open  into  the  outer  wall 
of  the  middle  meatus,  perforating  the 
bulla  ethmoidalis,  which  is  a  rounded 
projection  on  the  outer  wall  beneath  the 
middle  turbinated  bone.  The  posterior 
cells  open  still  farther  back  beneath  the 
superior  turbinated  bone  in  the  superior 
meatus.  In  disease  of  these  cells,  pus 
from  the  middle  and  anterior  ones  will 
show  in  the  middle  meatus;  from  the 
posterior  cells  in  the  superior  meatus.  In  this  latter  case  it  is  to  be  detected  pos- 
teriorly by  means  of  the  rhinoscopic  mirror.  Access  to  the  cells  is  obtained  by 
removing  the  middle  turbinated  bone.  This  is  done  by  dividing  it  into  two  pieces 
by  a  transverse  cut  with  forceps  or  scissors  and  then  removing  the  two  halves  with 
a  snare.     By  means  of  probes,  curettes,  and  forceps,  the  openings  into  the  cells  may 


Fig.  125. — Probes  introduced  into  the  frontal,  max- 
illary, and  sphenoidal  sinuses.  The  anterior  portion  of  the 
middle  turbinate  has  been  removed. 


THE    NOSE. 


103 


be  discovered  and  enlarged  as  thought  necessary.  The  region  of  the  ethmoidal  cells 
is  that  from  which  mucous  polypi  of  the  nose  take  their  origin.  They  are  a  common 
accompaniment  of  suppuration  of  the  accessory  nasal  cavities.  They  are  usually 
removed  by  snares  introduced  through  the  anterior  nares  or  more  rarely  by  forceps. 
Caries  affecting  the  anterior  cells  may  extend  into  the  orbit  and  the  pus  may  form  a 
fluctuating  tumor  above  the  inner  canthus  of  the  eye.  Care  should  be  taken  not  to 
mistake  a  meningocele  for  such  a  tumor. 

The  sphenoidal  sinuses  are  the  most  posterior,  lying  still  farther  back  than 
the  ethmoidal.  They  open  into  the  spheno-ethmoidal  recess  above  and  posterior 
to  the  superior  turbinated  bone.  Discharge  from  them  goes  into  the  pharynx  and  is  to 
be  seen  with  the  rhinoscopic  mirror.  They  can  be  reached  by  first  removing  the 
middle  turbinated  bone  and  then  introducing  a  probe  upward  and  backward  from  the 
anterior  nares  for  a  distance  of  7. 5  cm.  (3  in.  )  in  women  and  8  cm.  in  men.  They  can 
be  drained  by  cutting  away  their  anterior  wall  with  punch  forceps  introduced  through 
the  anterior  nares. 

The  maxillary  sinus  Hes  beneath  the  orbit  and  to  the  outer  side  of  the  nasal 
fossee.  It  is  the  seat  of  tumors,  often  malignant,  and  inflammation;  the  latter 
accompanied  by  an  accumulation  of  mucus  or 
pus.  The  walls  of  the  sinus  are  thin,  so  we 
find  tumors  bulging  forward,  causing  a  protrusion 
of  the  cheek.  They  press  inward  and  obstruct 
the  breathing  through  that  side  of  the  nose,  or 
they  push  upward  and  cause  protrusion  of  the 
eye  by  encroaching  on  the  orbit.  In  operating 
on  these  tumors,  the  superior  maxilla  is  usually 
removed ;  the  lines  of  the  cuts  through  the  bones 
being  shown  in  Fig.  64.  In  prying  the  bone 
down  posteriorly,  it  may  not  be  torn  entirely  away 
from  the  pterygoid  processes  and  some  plates  of 
bone  may  be  left  attached.  This  should  be  borne 
in  mind  in  operating  for  malignant  growths.  The 
sphenoidal  cells  are  behind  the  upper  posterior 
portion  of  the  maxillary  sinus,  therefore  in  oper- 
ating on  Meckel's  ganglion,  if  too  much  force  is 
used  in  breaking  through  the  posterior  wall  of 
the  antrum,  the  instrument  may  pass  across  the 
sphenomaxillary  fossa,  a  distance  of  about  3  mm. , 
and  open  the  sphenoidal  sinus. 

The  infra-orbital  nerve  is  usually  separated 
from  the  cavity  of  the  sinus  by  a  thin  shell  of 
bone.  At  the  upper  anterior  portion  of  the  sinus 
there  may  be  a  small  cell  between  the  bony  canal 

in  which  the  nerve  runs  and  the  bony  floor  of  the  orbit.  The  superior  dental  nerves 
reach  the  upper  teeth  usually  by  going  through  minute  canals  in  the  bone,  but  some- 
times, particularly  the  middle  set  supplying  the  bicuspid  teeth,  may  run  directly  beneath 
the  mucous  membrane,  and  thus  be  irritated  by  troubles  originating  within  the  sinus. 

■  The  inflammatory  and  infectious  diseases  of  the  sinus  originate  either  by  extension 
from  the  nose  or  the  teeth.  The  sinus  opens  into  the  nose  by  a  slit-like  opening  into  the 
middle  meatus  about  its  middle,posterior  to  the  hiatus  semilunaris  and  2. 5  cm.  above  the 
floor  of  the  nose.  When  the  opening  is  close  to  the  hiatus,  liquids  may  run  into  it  from 
the  hiatus.  The  bone  beneath  the  hiatus  and  opening  almost  down  to  the  floor  of  the 
nose  is  quite  thin,  so  that  the  sinus  can  readily  be  drained  by  thrusting  a  trocar  and  can- 
nula through  the  outer  wall  of  the  nose  into  the  sinus  just  below  the  hiatus  semilunaris. 
The  sinus  is  also  opened  from  the  front  through  the  canine  fossa  to  the  outer  side  of 
the  canine  tooth.  This  opening  affords  direct  access  to  the  cavity,  but  is  some  distance 
above  the  floor,  thus  it  does  not  drain  the  cavity  completely.  The  roots  of  the  upper 
teeth  project  into  the  antrum  forming  elevations,  usually  covered  by  a  thin  plate  of  bone. 
This  is  particularly  the  case  of  the  first  and  second  molars.  Disease  of  the  roots  of  these 
teeth  frequently  infects  the  antrum  and  drainage  is  often  made  through  their  sockets. 

*See  article  by  H.  H.  Stark  on  Sudden  Blindness  Due  to  Suppuration  of  the  Accessory 
Nasal  Sinuses,  J.  A.  M.  A.,  Oct.  30,  1915. 


Fig.  126.- 


-Side  view  of  the  maxillary  and 
frontal  sinuses. 


I04 


APPLIED    ANATOMY. 


THE  MOUTH   AND   THROAT. 

The  lips  are  formed  mainly  by  the  orbicularis  oris  muscle  with  its  subdivisions 
and  the  accessory  facial  muscles  (buccinator,  levator  and  depressor  anguli  oris, 
levator  labii  superioris,  levator  labii  superioris  akeque  nasi,  the  zygomaticus  major 
and  minor,  and  the  depressor  labii  inferioris).  The  orbicularis  oris  is  attached  tc 
the  superior  maxilla  in  the  incisor  fossa  above  the  second  incisor  tooth  and  also 
above  to  the  septum.  In  the  lower  lip  it  is  attached  to  the  mandible  beneath  the 
second  incisor  tooth.  The  lips  contain,  beside  muscular  tissue,  some  areolar  tissue, 
arteries,  veins,  and  lymphatics.  The  muscular  fibres  are  inserted  into  the  skin.  The 
mucous  membrane  lining  the  lips  has  lying  beneath  it  some  mucous  glands.  They 
sometimes  become  enlarged  and  form  small,  shot-like,  cystic  tumors  containing  mucus. 

Affections  of  the  Lips. — The  lips  are  affected  by  wounds,  angioma  or  blood 
tumor,  cancer  {epithelioma),  and  clefts  {harelip).  Wounds  of  the  lip  when  properly 
approximated  heal  readily  on  account  of  the  free  blood  supply.     The  arteries  sup- 


Auricularis  superior 


Occipitalis 
Auricularis  anterior 

Auricularis  posterior 


Zygomaticus  major 
Zygomaticus  minor' 

Levator  anguli  oris 

Levator  labii  superioris 

Buccinator 

Risorius 


Frontalis 

Gorrugator  supercilii 
Orbicularis  palpebrarum 
Orbital  part  of  same  muscle 
Pyramidalis  nasi 

—  Lev.  labii  sup.  alaeque  nasi 
—  Compressor  narium 

^  [Oilatores  naris 

~~"  Depressor  aloe  nasi 

Orbicularis  oris 

Depressor  anguli  oris 
Depressor  labii  inferioris 
Levator  nienti 


Platysma 


Fig.  127. — Superficial  dissection,  showing  the  muscles  of  the  head  and  face.    (Piersol.) 


plying  the  lips  are  the  superior  and  inferior  coronary  branches  of  the  facial.  They 
are  given  ofT  about  opposite  the  angle  of  the  mouth  and  pierce  the  muscle  to  run 
beneath  the  mucous  membrane  about  midway  betwen  the  edge  of  the  lip  and  its 
attachment  to  the  gums  or  nearer  the  free  border  of  the  lip.  Therefore,  in  operating 
on  the  lip,  the  artery  should  be  looked  for  in  this  situation  and  not  toward  the  skin 
surface  or  in  the  substance  of  the  lip.  The  superior  coronary  sends  a  branch  to  the 
nasal  septum,  called  the  inferior  artery  of  the  septum.  In  the  sulcus  between  the 
lower  lip  and  chin  lies  the  inferior  labial  artery.  The  bleeding  from  this  branch  is 
not  so  free  as  that  from  the  coronary  arteries,  because  the  anastomosis  across  the 
median  line  is  not  so  marked. 

Angioma. — The  blood-vessels,  mainly  the  veins,  of  the  lips  sometimes  become 
enlarged,  forming  a  large  protrusion.  This  may  be  noticed  at  or  soon  after  birth 
as  a  dusky  blue,  slightly  swollen  spot  on  the  lip.  As  the  child  grows  the  swelling 
enlarges.  Sometimes  it  enlarges  rapidly  and  operation  is  necessary  to  check  its 
growth;  otherwise  it  may  involve  a  large  portion  of  the  face  and  prove  incurable.  It 
is  composed  of  dilated  veins  with  thin  walls  and  large  lumen.  It  does  not  pulsate 
and  disappears  under  pressure,  only  to  return  when  this  is  removed.  It  is  treated 
by  excision.  The  thin  skin  is  dissected  off  and  the  growth  cut  away  from  the  tissues 
beneath,  the  bleeding  being  controlled  by  pressure,  haemostats,   and  ligatures.      In 


THE   MOUTH   AND   THROAT.  105 

the  case  figured,  the  facial  vein,  as  it  crossed  the  mandible,  and  the  transverse  facial 
vein  were  obliterated  by  means  of  acupressure  pins  passed  beneath  them,  and  the 
growth  was  excised. 

Cancer  or  epithelioma  of  the  lip  almost  always  affects  the  lower  and  not  the 
upper  lip.     The  disease  extends  through  the  lymphatics.      These  pass  down  and  out 


Fig.  128. — Angioma  involving  the  right  half  of  the  upper 
lip  in  a  child.     (Personal  sketch.) 


Fig.  129. — Single  harelip. 


from  the  lips  to  the  submaxillary  lymph-nodes  and  then  to  the  nodes  along  the 
great  vessels  of  the  neck.  It  is  in  these  regions  that  lymphatic  infection  is  usually 
seen.  The  middle  of  the  lower  lip  is  drained  into  a  node  in  the  submental  region  in 
front  of  the  submaxillary  nodes. 
This  also  is  sometimes  involved. 
In  operating  for  cancerous 
growths  it  is  advisable  to  re- 
move all  nodes  from  both  the 
submental  and  submaxillary  tri- 
angles. 

Cleft  or  harelip  is  so  named 
from  its  resemblance  to  the  lip 
of  a  hare.  It  is  a  deformity  due 
to  lack  of  development,  in  which 
the  lip  is  cleft  or  split  from  the 
mouth  up  into  the  nostril,  and 
sometimes  even  back  through 
the  hard  and  the  soft  palate. 
When  the  cleft  is  slight,  it  may 
not  reach  the  nostril.  It  is 
practically  always  to  one  side  of 
the  middle,  going  toward  one 
nostril.  Sometimes  the  harelip 
is  double,  involving  both  sides. 
In  such  cases  the  bone  between 
the  two  clefts  may  protrude.  In 
the  development  of  the  face,  the 
frontonasal  process  comes  down 
from  above  to  form  the  middle 
portion  of  the  nose,  upper  lip. 


Fig.  130. — Double  harelip,  showing  the  projecting  premaxilla. 


and  upper  jaw.  It  forms  a  bone  known  as  the  premaxilla  and  bears  the  incisor  teeth. 
From  the  sides  spring  the  nasal  and  maxillary  processes.  These  join  together  as  one 
process  and  grow  toward  the  premaxilla.     If  this  process  fails  to  reach  the  premaxillary 


io6 


APPLIED   ANATOMY. 


bone,  a  cleft  is  left  constituting  harelip.     If  both  processes  fail  to  reach  the  premaxilla, 
a  double  harelip  is  formed;  the  cleft  may  extend  through  the  hard  and  the  soft  palate— 


Frontonasal  process 

Medial  nasal  process 


Nasal  pit 

Lateral  nasal  process 


Lachrymonasal  furrow 


Maxillary  process 
First  visceral  arch 

Mandibular  process 
First  visceral  furrow 
Second  visceral  arch 
Second  visceral  furrow 
Third  visceral  arch 


Pig.  131. — Frontal  view  of  human  foetus  about  four  weeks  old.    (After  His.) 

the  cleft  palate  may  alone  be  present  as  seen  in  Fig.  139  (see  page  112).    In  operating  foi 
harelip,  the  two  sides  of  the  cleft  are  freshened  and  sewed  together,  thus  closing  the  cleft. 


Fig.  132. — Paralysis  of  depressor  labii  inferioris  from  section  of  the  lower  filament  of  the  facial  nerve.    (McDowd.> 

Paralysis  of  the  lips  is  due  to  interference  with  the  functions  of  the  seventh  nerve. 
The  muscles  of  the  face  and  lip  are  supplied  by  the  seventh  or  facial  nerve.  This  is 
frequently  paralyzed,  for  owing  to  its  tortuous  passage  through  the  temporal  bone  in 
the  canal  of  Fallopius  it  is  injured  in  fractures  of  the  base  of  the  skull  and  becomes 


THE   MOUTH   AND   THROAT. 


107 


affected  from  middle  ear  disease  or  neuritis.  When  paralyzed,  the  muscles  of  the 
lips,  both  upper  and  lower,  on  the  affected  side,  droop.  The  drooping  of  the  lower  lip 
may  allow  the  saliva  to  run  out  of  the  mouth.  It  is  also  impossible  for  the  patient 
to  pucker  his  mouth,  as  in  whistling.  If  the  lesion  of  the  facial  nerve  is  inside  the 
skull  and  not  in  the  Fallopian  canal,  t\\e  great  petrosal  nerve  and  some  of  the  palatal 
muscles  will  be  paralyzed,  the  voice  will  be  altered  and  swallowing  interfered  with. 

The  depressor  labii  inferioris  instead  of  receiving  its  nerve  supply  from  the  supra- 
mandibular  branch  of  the  facial,  frequently  is  supplied  by  the  inframandibular  branch; 
pressure  or  injury  of  this  branch  in  enlargements  of  or  operations  on  the  submandib- 
ular lymph-nodes  has  produced  paralysis  of  the  muscle  with  a  peculiar  alteration  of 
the  facial  expression,  well  shown  (see  Fig.  132)  by  a  case  of  Dr.  McDowd  (Anrials  0/ 
Surgery,  July,  1905). 

Mouth. — Surface  Anatomy. — In  looking  into  the  mouth,  one  sees  the  tongue 
below  and  the  roof  above,  surrounded  in  front  and  on  the  sides  by  the  teeth.  On  each 
side  are  the  inner  surfaces  of  the  cheeks  and  posteriorly  are  seen  the  uvula,  the 


Hard  palate 

Junction  of  the  hard 
and  soft  palates 

Soft  palate 

Uvula 

Anterior  pillar  of  fauces 

Posterior  pillar  of  fauces 

Tonsil 


Fig.  133. — Interior  of  the  mouth. 

arches  of  the  palate,  and  the  pharynx.  On  the  mucous  membrane  of  the  cheek, 
opposite  the  second  upper  molar  tooth,  is  a  small  papilla  in  the  top  of  which  opens 
the  duct  of  the  parotid  gland.  A  small  probe  can  be  inserted  into  it  and  passed 
outward  and  backward  toward  the  gland. 

Tongue. — The  tongue  is  covered  with  a  mucous  membrane  which  is  modified 
skin;  therefore  it  is  subject  to  the  same  diseases  as  the  skin.  It  is  covered  with 
papillae  of  three  kinds — the  filiform,  ftaigiform,  and  circnnivallate.  The  filiform 
are  the  smallest  and  most  numerous  and  form  a  sort  of  ground-work  in  which  the 
others  are  imbedded.  The  fungiform  are  larger  and  fewer  in  number  and  are  scattered 
on  the  dorsum,  sides,  and  tip  of  the  tongue  among  the  filiform.  The  circum vallate, 
seven  to  twelve  in  number,  form  a  V-shaped  row  at  the  base  of  the  tongue.  In  the 
eruptive  fevers,  particularly  scarlet  fever,  the  tongue  gets  very  red  and  the  papillae 
become  enlarged,  forming  what  is  known  as  the  strawberry  or  raspberry  tongue. 
Just  beyond  the  apex  of  the  circumvallate  papillae  in  the  median  line  is  the  foramen 
ccscuni.  It  is  sometimes  patulous  for  a  short  distance  and  is  the  upper  extremity  of 
the  remains  of  the  thyroglossal  duct. 


io8 


APPLIED    ANATOMY. 


On  the  posterior  portion  of  the  tongue  behind  the  circunivallate  papillse,  on 
each  side  of  the  median  Hne,  is  a  mass  of  adenoid  tissue  which  forms  what  is  known 
as  the  lingual  tonsil.  It  sometimes  becomes  hypertrophied  and  is  then  cut  off  with 
a  specially  curved  tonsillotome  just  as  is  done  with  enlarged  faucial  tonsils.  Run- 
ning from  the  base  of  the  tongue  to  the  epiglottis  are  three  folds,  called  the  7nedian 
and  lateral  glosso-epiglottic  folds. 

In  the  middle  of  the  dorsum  of  the  tongue  is  a  furrow;  this  is  caused  by  the 
septum  binding  the  middle  of  the  tongue  down  and  allowing  the  muscles  to  rise  on 
each  side. 

On  turning  the  tip  of  the  tongue  up  (Fig.  135),  a  fold  of  membrane,  Xho.  frcsnum, 
is  seen  extending  from  the  under  surface  to  the  floor  of  the  mouth  beneath.  In  new- 
born children,  this  fraenum  appears  sometimes  to  be  too  short,  hence  the  name  tongue- 
tie.     In  cutting  it,  the  split  end  of  a  grooved  director  is  placed  over  the  fraenum 


Posterior  nares; 
turbinated  bone 


Fossa  of  Rosenmiiller 
Eustachian  tube 

Faucial  tonsil 

Foramen  caecum 
Lingual  tonsil 

Cuneiform  tubercle  (Wrisberg) 

Comiculate  tubercle 
(Santorini) 

Sinus  pyriformis 
Cricoid  cartilage 


Fig.  134. — View  of  pharynx,  looking  forward;  posterior  wall  removed,  showing  the  posterior  nares,  base  of  tongue, 

and  opening  of  the  larynx. 

and  the  tongue  pushed  back.  This  makes  the  freenum  tense  and  it  can  readily  be 
snipped  with  the  scissors.  Care  should  be  taken  not  to  cut  too  deeply,  or  the  ranine 
artery  may  be  cut  and  cause  troublesome  bleeding.  Running  across  the  floor  of  the 
mouth,  between  the  teeth  and  tongue,  parallel  to  the  alveolus,  is  the  sublingnal  ridge, 
formed  by  the  sublingual  gland.  This  gland  lies  on  the  mylohyoid  muscle  beneath 
and  the  lower  jaw  in  front.  On  each  side  of  the  fraenum  on  the  sublingual  ridge  is  a 
papilla  into  which  the  duct  of  the  submaxillary  gland,  \VJiar ton  s  duct,  opens.  Open- 
ing into  Wharton's  duct,  or  by  a  separate  duct  into  the  same  papilla,  is  the  duct  of 
the  sublingual  gland,  called  the  duct  of  Rivinus  or  Bartholin.  The  superficial  por- 
tion of  the  gland  opens  on  the  sublingual  ridge  to  the  outer  side  of  the  papilla  by  a 
number  of  small  ducts,  called  the  ducts  of  IValthcr. 

Ranula  is  the  name  given  to  a  cyst  occurring  in  connection  with  the  salivary 
glands.      Such  cysts  involving  the  parotid  gland  are  quite  rare,  so  that  the  term 


THE   MOUTH   AND   THROAT. 


109 


is  usually  restricted  to  those  of  the  submaxillary  and  sublingual  glands.  The 
mylohyoid  muscle  forms  the  floor  of  the  mouth  and  these  cysts  lie  on  it  beneath 
the  tongue  and  between  the  tongue  and  the  gums  (Fig.  136).  If  the  cyst  is  large  it 
causes  a  protrusion  or  swelling  beneath  the  jaw.  The  bulk  of  the  submaxillary  gland 
lies  on  the  side  of  the  mylohyoid  muscle  nearest  the  skin;  only  a  small  portion  of  it 


Fraenum 


Sublingual  ridge 

Orifice  of 
sublingual  and 
submaxillary  ducts 


Fig.  135. — Under  surface  of  tongue  and  floor  of  mouth. 


winds  around  the  posterior  edge  of  the  muscle.  Therefore,  cysts  involving  the  sub- 
stance of  the  gland  would  show  in  the  submaxillary  region  of  one  side.  If,  how^ever, 
the  duct  were  obstructed  (as  by  a  calculus)  it  would  form  a  cyst,  which  would  bulge 
into  the  mouth  beneath  the  tongue  and  be  called  a  ranula.  The  sublingual  gland  is 
usually  the  starting  point  of  these  cysts,  and  it  will  be  seen  that  as  they  enlarge  they 


Cyst 


Fig,  136. — Sublingual  cyst  (ranula).     (From  a  photograph  by  Dr.  Ashhurst.) 

push  the  ranine  artery  with  the  tongue  backward  and  are  only  covered  by  the  mucous 
membrane.  On  this  account  there  is  little  or  no  danger  in  operating  on  them. 
They  are  either  dissected  out  or  the  front  wall  of  the  cyst  cut  away  and  the  interior 
cauterized  or  packed  with  gauze  to  promote  the  formation  of  granulations.  The 
jaw-bone  is  in  front  of  them  and  the  mylohyoid  muscle  beneath.  Posteriorly  lies  the 
duct  of  the  submaxillary  gland  and  the  ranine  artery. 


APPLIED    ANATOMY. 

Mucous  cysts  can  occur  from  the  mucous  glands  of  the  mouth  and 
There  is  a  ghmd  on  the  under  side  of  the  tip  of  the  tongue,  usually  larger  than  the 
others,  called  the  anterior  lingual  gland  or  gland  of  Nuhn.  As  a  rule,  these  mucous 
cysts  are  small  and  are  felt  as  hard  rounded  bodies  beneath  the  mucous  membrane. 
Derrrioid  cysts  occur  in  connection  with  the  tongue  but  very  rarely. 

Carcinoma  of  the  tongue  is  a  moderately  frequent  disease  and  as  the  tongue  is 
covered  by  modified  skin,  the  cancer  is  of  epithelial  type.  It  begins  on  the  surface 
of  the  tongue  either  by  a  change  in  the  epithelial  covering  or  else  in  fissures  or  ulcers 
at  its  edges. 

The  lymphatics  of  the  tongue  pass  to  the  submaxillary  nodes  beneath  the  jaw 
and  thence  to  the  deep  cervical  nodes  along  the  great  vessels  or  directly  to  the  latter 
without  passing  through  the  submaxillary  nodes.  If  the  disease  exists  for  any  length 
of  time,  these  are  the  nodes  that  become  infected.  They  are  only  to  be  reached  by 
an  incision  in  the  neck. 

The  arteries  of  the  tongue  are  the  lingnal  a?id  its  branches,  the  hyoid,  the 
dorsalis  linguce,    sublingical,    and  ranine.      In  removing    the   tongue,   the   lingual 


Anterior  lingual  gland 


—  Ranine  artery 


Lingual  nerve 


Orifice  of  submaxillary 
and  sublingual  glands 

-  Sublingual  gland 


Fig.  137.— Under  surface  of  the  tongue,  mucous  membrane  removed. 

artery  on  the  side  to  be  removed  is  sometimes  ligated  in  the  neck ;  this  cuts  of^  the 
blood  supply  to  that  side  and  there  is  practically  no  bleeding.  There  is  very  little 
anastomosis  between  the  vessels  of  the  two  sides  of  the  tongue.  The  arteries  run 
lengthwise  through  the  tongue,  so  that  in  glossitis  or  inflammatory  swelli)ig  of  the 
tongue,  incisions  should  always  be  made  longitudinally  into  it. 

The  ligation  of  the  lingual  artery  will  be  found  described  in  the  section  on  the 
neck.  As  the  lingual  artery  passes  above  the  hyoid  bone,  it  gives  off  its  flrst  branch, 
the  hyoid.  It  is  quite  small  and  goes  above  the  hyoid  bone  superficial  to  the  hyo- 
glossus  muscle.  The  lingual  then  goes  beneath  the  hyoglossus  muscle  and  near  the 
posterior  edge  gives  of?  its  second  branch  or  dorsalis  linguce. 

In  excision,  the  tongue  is  usually  cut  through  on  the  distal  side  of  the  dorsalis 
linguae  artery.  When  this  is  the  case,  the  bleeding  which  occurs  from  the  branches 
of  the  dorsalis  linguae  is  not  marked  because  it  is  not  a  large  artery. 

In  order  to  draw  the  tongue  out,  it  must  be  loosened  posteriorly  by  cutting  the 
anterior  pillars  of  the  fauces  and  palatoglossus  muscle,  and  anteriorly  at  the  fraenum 
by  cutting  the  geniohyoglossus  muscle.     By  drawing  the  tongue  up,  the  ranine  artery 


THE   MOUTH   AND   THROAT.  in 

is  drawn  out  of  the  way  and  there  will  be  only  slight  bleeding  from  small  branches 
of  the  sublingual,  which  comes  from  the  main  trunk  at  the  anterior  edge  of  the  hyo- 
glossus  muscle.  From  this  point  forward  to  the  tip,  the  lingual  artery  is  called  the 
ranine.  The  tongue  having  been  loosened  and  pulled  out,  Mr.  Jacobson  makes  a 
transverse  cut  through  the  mucous  membrane  behind  the  growth  and  then,  by  push- 
ing the  tissues  aside  with  a  blunt  instrument,  exposes  the  hngual  nerve  and  artery 
lying  together  beneath  the  mucous  membrane.  The  artery  is  then  tied  and  the 
growth  removed. 

In  order  to  secure  any  bleeding  points  after  the  tongue  has  been  cut  away,  the 
floor  of  the  mouth  can  be  raised  and  pushed  forward  by  the  fingers  beneath  the  chin. 


Styloglossus  muscle 
Hyoglossus  muscle 


Lingual  nerve 


Submaxillary 
ganglion 


Geniohyoglossus  muscle 
Ranine  artery 

Ranine  vein 


Sublingual  gland 

Submaxillary  duct 

Fig.  138. — The  cheek  has  been  split,  the  tongue  drawn  forward,  and  the  mucous  membrane  removed  from 
its  under  surface,  exposing  the  ranine  artery  and  vein,  the  lingual  and  hypoglossal  nerves,  the  sublingual  gland, 
the  submaxillary  ganglion,  and  the  duct  of  the  submaxillary  gland. 

This  brings  the  stump  into  view  and  within  reach.  If  lymphatic  nodes  are  to  be 
removed,  they  must  be  sought  for  by  an  additional  incision  on  the  outside  beneath 
the  jaw. 

The  roof  of  the  mouth  is  formed  by  the  hard  palate  and  the  soft  palate ;  the 
former  comprising  about  three-fourths  and  the  latter  one-fourth.  The  hard  or  bony 
palate  is  composed  in  its  anterior  two-thirds  of  the  palatal  processes  of  the  superior 
maxillary  bones,  and  in  its  posterior  third  of  the  palatal  bones.  In  the  median  line 
close  to  the  incisor  tooth,  in  the  dried  skull,  is  the  anterior  or  nasopalatine  foranieii. 
This  is  subdivided  into  four  foramina,  two  lateral  and  two  anteroposterior.  The 
former,  called  the  foramina  of  Stenson,  transmit  the  terminal  branches  of  the  de- 
scending palatine  arteries;  of  the  latter,  c-A}\QA\\'\^fo7'amina  of  Scarpa,  the  anterior  one 
transmits  the  left  nasopalatine  nerve,  and  the  posterior  one  the  right  nasopalatine 
nerve.  The  soft  tissues  of  the  roof  of  the  mouth  are  thicker  than  they  appear  to  be, 
so  that  when  they  are  raised,  as  in  operating  for  cleft  palate,  they  form  quite  a  thick 
layer.  Infection  of  the  roof  of  the  mouth  when  it  occurs  is  usually  by  extension  from 
neighboring  diseased  teeth,  abscesses  being  sometimes  produced. 

The  blood  supply  of  the  roof  is  of  importance  in  relation  to  the  operation  for  cleft 
palate  {staphylorrhaphy)  (Fig.  139).  The  blood  comes  anteriorly  from  the  nasopala- 
tine arteries  and  posteriorly  from  the  descending  palatine  arteries,  which  come  down 


APPLIED    ANATOMY. 

through  the  pterygopalatine  canal  from  the  internal  maxillary  artery  and  make  their 
appearance  on  the  hard  palate  at  the  posterior  palatine  foramen.  This  foramen  is  on 
the  roof  of  the  mouth  opposite  the  last  molar  tooth  and  0.5  cm.  to  the  inner  side  and 
in  front  of  the  hamular  process  (Fig.  140).     This  hamular  process  can  be  felt  just  pos- 


Opening  of  the 
pharyngeal  pouch 


Fig.  139. — Cleft  palate,  showing  the  opening  of  the  pharyngeal  pouch  on  the  posterior  wall. 

terior  and  to  the  inner  side  of  the  last  molar  tooth.  If,  in  operating  for  cleft  palate,  the 
tissues  are  loosened  from  the  bone  too  close  to  the  hamular  process,  this  artery  may  be 
torn  near  its  exit  from  the  foramen,  in  which  case  the  bleeding  is  very  free.  To  control 
it,  the  canal  can  be  plugged  with  a  slip  of  gauze.      In  detaching  the  soft  palate  from 


Posterior  or  descending 
palatine  artery 


Hamular  process 
Tensor  palati  muscle 


Fig.  140. — Roof  of  the  mouth,  mucous  membrane  removed. 

the  posterior  edge  of  the  hard  palate,  it  should  be  remembered  that  this  attachment 
is  quite  strong.  Not  only  are  the  muscles  of  the  soft  palate  themselves  attached  to 
the  bone,  but  the  pharyngeal  aponeurosis  which  lies  under  the  mucous  membrane  on 
the  posterior  or  upper  surface  of  the  soft  palate  is  also  attached  to  the  bone. 

Palatal  Arches. — Farther  back  in  the  mouth,  one  sees  the  anterior  and  pos- 
terior arches  of  the  palate  or  pillars  of  the  fauces  with  the  uvula.     The  anterior 


THE    MOUTH    AND   THROAT. 


113 


pillar  runs  from  the  soft  palate  to  the  tongue  and  is  formed  by  the  palatoglossus 
muscle.  The  posterior  pillar  runs  from  the  soft  palate  downward  to  the  sides  of  the 
pharynx  and  is  formed  by  \\\it  palatopharyngeus  muscle.     In  front  of  these  arches  and 


'Pharyngeal  tonsil 


Fossa  of  Rosenmuller 
Eustachian  tube 

Supratonsillar  fossa 

Pterygomandibular  fold 
Plica  triangularis 

Anterior  pillar 
Faucial  tonsil 
Posterior  pillar 

Epiglottis 


Fig.  141. — Lateral  view  of  the  faucial  tonsil  and  pharyngeal  region 


running  from  the  roof  of  the  mouth  opposite  the  posterior  edge  of  the  last  molar  tooth 
downward  to  the  posterior  edge  of  the  alveolar  process  of  the  lower  jaw  is  an  elevation 
of  the  mucous  membrane  which  shows  the  line  of  junction  of  the  hard  and  soft  palates. 


Fig.  142. — Diagram  illustrating  the  blood  supply  of  the  faucial  tonsil. 

Faucial   Tonsils. — Between  the  pillars  of  the  fauces  lie  t\\it  faucial  tonsils. 
They  are  limited  above  by  the  sulcus,  called  the  supratonsillar  fossa,  formed  by  the 
approximation  of  the  pillars  and  a  fold  of  mucous  membrane,  called  the  plica  trian- 
gularis (His),  running  downward  from  the  anterior  pillar  and  often  blending  with 
8 


114 


APPLIED    ANATOMY. 


the  tonsil.  Below  they  extend  a  variable  distance,  necessitating  depression  of  the 
tongue  with  a  spatula  in  order  to  make  their  lower  limit  accessible.  They  lie  opposite 
the  angles  of  the  jaw  on  the  pharyngeal  aponeurosis  (p.  ii6)  with  the  superior  con- 
strictor muscle  and  bucco-pharyngeal  fascia  outside.  A  knowledge  of  their  structure 
is  essential  to  the  proper  treatment  of  their  diseases.  The  tonsils  are  oval  in  shape  and 
when  normal  in  size  project  but  little  beyond  the  pillars  of  the  fauces.  They  are  about 
2. 5  cm.  long  by  i  cm.  wide  and  consist  of  about  a  dozen  recesses  or  crypts  formed 
by  the  folding  inward  of  the  mucous  membrane.  From  these  crypts  follicles  extend. 
The  walls  of  the  crypts  contain  adenoid  tissue  as  well  as  mucous  glands.  The  tonsil 
is  held  together  by  connective  tissue  which  is  contmuous  with  its  capsule  and  the 
submucous  fibrous  tissue  of  the  pharynx.  This  capsule  rests  on  and  blends  more  or 
less  completely  with  the  fibres  of  the  pharyngeal  aponeurosis.  On  this  account  while 
an  enlarged  tonsil  can  at  times,  usually  in  young  children,  be  shelled  out  of  its  bed, 
especially  its  upper  portion,  at  others  it  is  necessary  to  dissect  or  cut  it  out  by  means 
of  a  knife,  scissors,  tonsillotome,  or  snare. 

The   blood-vessels  supplying  the  tonsil  are  five  in  number.       They   are  :  the 


Fig.  143. — Point  of  puncture  for  tonsillar  abscess.  "  If  an  imaRinary  horizontal  line  is  drawn  across  the 
base  of  the  uvula,  and  another  vertically  along  the  anterior  faucial  pillar,  they  will  intersect  at  a  jwint  overlying 
the  supratonsillar  fossa.  Just  externaJ  to  this  is  utte  best  point  for  opening  a  quinsy." — St.  Clair  Thomson,  M.D., 
Brii.  M.  J.,  March  25,  1905,  p.   645. 

ascending  pharyngeal  branch  of  the  external  carotid,  the  ascending  palatine  and 
tonsillar  branches  of  the  facial,  the  tonsillar  branch  of  the  dorsalis  linguce,  and  the 
desce?iding  palatine  branch  of  the  internal  maxillary.  Ordinarily,  these  branches  are 
small,  but  sometimes  some  of  them  are  large  and  may  cause  troublesome  hemorrhage. 
In  inflammation  of  the  tonsils,  these  vessels  of  course  are  larger  than  usual. 

The  tonsils  are  subject  to  inflammation  and  tumors.  Tumors  are  rare;  they 
grow  inward  and  obstruct  breathing  and  swallowing.  Attempts  are  made  to  remove 
them  either  by  scraping,  cutting,  snaring,  or  burning  them  with  the  electrocautery 
from  the  mouth;  or  they  are  sometimes  removed  through  an  external  incision  through 
the  neck.  This  latter  is  a  very  severe  procedure  on  account  of  the  depth  of  the 
tonsil  and  the  number  of  important  structures  which  overlie  it. 

Tonsillitis  or  quinsy  is  an  inflammation  of  the  tonsils  which  leads  to  the  for- 
mation of  an  abscess.  In  mild  cases  the  crypts  or  lacunae  are  affected,  forming  a 
follicular  or  lacunar  tonsillitis.  In  this  form  epithelium  and  inflammatory  matter  are 
poured  into  the  follicles  and  distend  them,  often  showing  as  white  plugs  protruding 
from  the  mouth  of  the  crypt.  In  its  treatment,  in  addition  to  local  applications, 
surgeons  enlarge  the  openings  into  the  crypts  with  a  small  knife  and  scoop  the  con- 
tents out  with  a  sharp  spoon.  In  severe  cases,  the  whole  substance  of  the  tonsil 
and  even  the  connective  tissue  around  it  are  involved  in  the  inflammation,  forming 
a  parenchyftiatous  tonsillitis.  It  frequently  proceeds  to  the  formation  of  pus.  When 
this  forms  in  the  substance  of  the  tonsil  it  may  break  into  a  follicle  and  discharge  into 
the  throat.     An  abscess  of  the  tonsil  may  become  quite  large,  bulging  toward  the 


THE   MOUTH   AND   THROAT. 


IIS 


median  line,  and  on  breaking  may  cause  suffocation  by  passage  of  the  pus  into  the 
larynx.  If,  as  is  usually  the  case,  the  pus  involves  the  tissue  around  the  tonsil,  form- 
ing a  peritonsillar  abscess,  it  pushes  upward  behind  the  anterior  pillar  into  the  supra- 
tonsillar  fossa  and  bulges  forward,  stretching  the  pillar  over  it.  To  evacuate  this  pus 
an  incision  should  be  made  directly  anteroposteriorly,  with  the  flat  side  of  the  blade 
parallel  with  the  edge  of  the  pillar,  or  a  slender  pair  of  haemostatic  forceps  may  be  used. 
A  centimetre  and  a  quarter  (}^  in.)  is  deep  enough  usually  to  plunge  the  knife;  the 
point  should  not  be  pointed  outwardly  but  directly  backward.  The  incision  should 
be  just  above  the  upper  and  lateral  edge  of  the  anterior  pillar  (Fig.  143).  Some 
small  vessels  may  bleed,  but  this  will  either  stop  spontaneously  or  may  be  controlled 
by  packing.  The  ascending  pharyngeal  artery  lies  beneath  the  tonsil.  The  tonsil 
lies  on  the  pharyngeal  aponeurosis  and  the  superior  constrictor  muscle,  while  the  as- 


Anterior  pillar 


Tonsil 


Posterior  pillar 


Styloglossus 

Stylopharyngeus 

Stylohyoid 

Internal  carotid  artery 

Internal  jugular  vein 

Digastric 

Stemomastoid 


Longus  colli 


Rectus  capitis  anticus  major 


Pig.  144. — Transverse  frozen  section  passing  through  the  faucial  tonsil  and  showing  its  relation  to  the  internal 

carotid  artery. 

cending  pharyngeal  artery  and  external  carotid  lie  outside  of  them,  so  that  both 
structures  would  have  to  be  cut  before  the  vessels  would  be  wounded.  The  internal 
carotid  artery  lies  still  deeper  (2  to  2.5  cm.)  behind  and  external  to  the  tonsil.  It  is 
usually  well  out  of  harm's  way  unless  dilated  (see  page  123,  Fig.  156),  but  the  pus  may 
burrow  into  it  and  cause  fatal  hemorrhage.  Sometimes  pus  may  burrow  through  the 
constrictor  muscle  and  enter  the  tissues  of  the  neck.  In  severe  tonsillitis  the  deep 
lymphatics  beneath  the  angle  of  the  jaw  become  enlarged. 

Hypertrophy  of  the  tonsils  is  common  and  is  treated  by  removing  them  entirely  or 
level  with  the  palatal  arches.  An  instrument  called  the  tonsillotome  is  used,  or  it 
is  done  with  a  knife  or  scissors  or  snare.  Fatal  bleeding  has  followed  this  oper- 
ation. The  blood  supply  to  the  tonsil  has  already  been  given.  If  the  bleeding  is  so 
free  as  to  threaten  the  life  of  a  patient,  the  external  carotid  artery  should  be  ligated 
as  all  the  vessels  supplying  the  tonsil  are  derived  from  it. 


ii6 


APPLIED  ANATOMY. 


Enucleation  is  performed  by  grasping  the  tonsil  with  toothed  forceps,  drawing  it 
out,  and  cutting  it  loose  with  knife,  scissors,  or  snare  from  its  attachments  to  the  pil- 
lars and  aponeurosis  beneath.  Sometimes  after  loosening  its  attachments  above  it  is 
torn  loose  or  shelled  out,  from  above  downward,  by  the  finger  or  a  blunt  instrument. 
On  account  of  the  attachment  of  the  capsule  to  the  pharyngeal  aponeurosis  the  tonsil 
cannot  always  readily  be  ' '  shelled  out ' '  and  portions  may  remain  and  require  to  be 
removed  with  the  forceps  and  scissors  or  tonsillar  punch.  The  incision  through  the 
mucous  membrane  should  begin  posterior  to  the  free  edge  of  the  plica  triangularis 
— not  anterior.  The  tonsil  grows  more  adherent  to  the  deep  structures  as  the  child 
increases  in  age.  It  is  a  disagreeable  and  bloody  procedure  and  is  often  done  under 
a  general  anaesthetic. 

Retropharyngeal  abscess  may  arise  from  any  one  of  three  causes, — cervical 
caries,  suppuration  of  lymphatic  nodes,  or  extension  of  pus  from  the  middle  ear 
through  the  canal  for  the  tensor  tympani  muscle.  The  pharyngeal  aponeurosis  lies 
under  the  mucous  membrane  and  between  it  and  the  constrictor  muscle.  It  is  thick 
above  and  fades  away  below.  It  fills  up  the  gap  above  between  the  superior  constric- 
tor and  the  base  of  the  skull  and  is  attached  to  the  pharyngeal  spine  on  the  under  surface 
of  the  basilar  process.  It  is  lined  with  the  mucous  membrane  and  covered  by  the 
constrictor  muscles.  Over  all  is  the  buccophary7igcaI  fascia,  a  thin  layer  continu- 
ous forward  over  the  buccinator  muscle  and  separated  from  the  prevertebral  fascia 


Fig.  145. — Cervical  caries  with  retropharyngeal  abscess  opening  just  posterior  to  the  stemomastoid  muscle. 

by  very  loose  connective  tissue.  The  space  between  these  two  layers  of  fascia 
is  known  as  the  retropharyiigeal  space  and  pus  'can  follow  it  downward  behind  the 
pharynx  and  oesophagus  into  the  posterior  mediastinum.  Retropharyngeal  abscesses 
occur  external  to  the  pharyngeal  aponeurosis  and  bulge  into  the  throat.  On  account 
of  the  looseness  of  this  aponeurosis  and  its  lack  of  firm  attachments,  these  abscesses 
may  not  bulge  forward  as  a  distinct  circumscribed  swelling,  as  abscesses  do  elsewhere, 
but  are  more  apt  to  gravitate  downward  and  hang  in  a  loose  bag-like  manner  opposite 
the  base  of  the  tongue.  They  are  not  easily  felt,  being  so  soft,  and  to  see  them  prop- 
erly the  tongue  should  be  held  down  with  a  tongue  depressor.  In  looking  for  their 
origin,  a  careful  examination  of  the  spine  should  be  made  to  detect  the  possible 
existence  of  spinal  caries  or  Pott 's  disease,  and  the  ear  should  be  examined  for  suppur- 
ative otitis  media.  The  lymph-nodes,  which  often  give  rise  to  these  abscesses,  espe- 
cially in  children  under  two  years  of  age,  are  one  or  two  lying  on  the  anterior  surface 
of  the  vertebral  column  between  it  and  the  pharyngeal  aponeurosis  and  constrictor 
muscles.  In  evacuating  these  abscesses  the  safest  way  is  to  place  the  child  on  its 
back  with  the  head  hanging;  the  pus  then  gravitates  toward  the  roof  of  the  pharynx. 
The  tongue  is  held  out  of  the  way  with  a  tongue  depressor  and  the  abscess  can  be 
well  seen  and  incised.      Raising  the  body  causes  the  pus  to  flow  from  the  mouth. 


THE    MOUTH    AND   THROAT. 


117 


The  pus  may  not  only  point  in  the  mouth  but  can  work  its  way  laterally.  In 
such  a  case  it  may  pass  out  behind  the  sheath  of  the  great  vessels  and  make  its 
appearance,  as  I  have  seen  it,  behind  the  posterior  edge  of  the  sternomastoid  muscle. 
If  a  tumor  is  present  in  this  situation,  the  pus  may  be  evacuated  by  an  incision  at 
this  point  and  the  abscess  drained  there  instead  of  making  an  opening  through  the 
pharynx.      This,  of  course,  tends  to  guard  against  infection  from  the  mouth. 

Lingual  Nerve. — The  lingual  nerve  or  gustatory  branch  of  the  fifth  can  be 
readily  exposed  in  the  mouth.  On  looking  into  the  mouth,  a  fold  can  be  seen  going 
up  and  back  just  behind  the  last  molar  tooth.  This  is  formed  by  ihe pteryg07na7tdib- 
ular  ligament,  running  from  the  tip  of  the  internal  pterygoid  plate  to  the  posterior 
extremity  of  the  mylohyoid  ridge  and  joining  the  buccinator  with  the  superior  con- 


Mandibular  (inferior 
dental)  nerve 

Mandibular  (inferior 
dental)  artery 

Mandibular  spine 
(Spix) 

Lingual  nerve 


Submaxillary  gland 


Submaxillary  duct 
Sublingual  gland 


Fig.  146. — View  of  mandibular  and  lingual  nerves  from  within. 

strictor  muscles.      An  incision  made  just  internal  to  this  fold,  below  and  behind  the 
last  molar  tooth,  will  lead  one  down  to  the  lingual  nerve  close  to  the  bone. 

The  mandibular  nerve  is  also  reached  through  an  incision  running  from  the 
last  upper  to  the  last  lower  molar  tooth.  The  finger  is  introduced  and  the  spine  of 
Spix  felt  at  the  inferior  dental  foramen.  The  nerve  and  artery  enter  the  mandible  at 
this  point,  the  artery  being  below  and  posterior.  The  operation  of  Paravicini  on  this 
nerve  through  the  mouth  is  unsatisfactory  on  account  of  the  lack  of  proper  exposure. 
It  is  better  to  attack  the  nerve  from  the  outside  as  detailed  on  page  60. 


PHARYNX. 

The  pharynx  is  the  common  air  and  food  tract  that  lies  behind  the  nose,  mouth, 
and  larynx.  It  extends  from  the  base  of  the  skull  above  to  the  oesophagus  below. 
Its  lower  end  is  at  the  cricoid  cartilage,  which  is  opposite  the  sixth  cervical  vertebra. 
In  passing  an  instrument  directly  backward  through  the  nose,  one  strikes  the  base  of 
the  skull  or  interval  between  the  basilar  process  and  the  atlas.  In  looking  into  the 
throat  through  the  mouth,  one  is  level  with  the  body  of  the  second  vertebra.  If,  by 
means  of  a  hook,  the  soft  palate  is  raised  or  pushed  aside  and  the  head  tilted  slightly 
backward  one  sees  the  anterior  tubercle  of  the  atlas.     The  rounded  projection  can 


ii8 


APPLIED    ANATOMY. 


readily  be  felt.  The  pharynx  has  seven  openings  into  it,  viz. :  the  two  posterior  nares, 
the  two  Eustachian  tubes,  the  mouth,  the  larynx,  and  the  cesophagus. 

Posterior  Nares  or  Choanse. — These  can  readily  be  seen  by  means  of  the  rhino- 
scopic  mirror.  They  are  separated  by  the  posterior  edge  of  the  bony  septum,  the 
vomer  bone.  They  are  2.5  cm.  (i  in.)  long  and  1.25  cm.  wide,  hence  are  of  sufifi- 
cient  size  to  allow  a  well  lubricated  little  finger  to  pass  into  them  from  the  anterior 
nares.  The  tip  of  an  index  linger  can  be  inserted  through  the  mouth  below,  hence 
the  entire  length  of  the  lower  meatus  of  the  nose  and  upper  surface  of  the  soft  palate 
can  be  palpated. 

Projecting  from  each  lateral  wall  toward  the  septum  are  the  rounded  posterior 
ends  of  the  middle  and  inferior  turbinated  bones.  Sometimes,  high  up,  the  posterior 
end  of  the  superior  turbinate  can  be  seen.  The  posterior  end  of  the  inferior  turbi- 
nate is  frequently  enlarged  by  a  swelling  of  its  membrane,  forming  a  posterior  hirbi- 

Septum 

Pharyngeal  tonsil 
Eustachian  tube 

Fossa  of  Rosenmuller 

— First  cervical  vertebra 

Lingual  tonsil 

Anterior  pillar ' '   "^"'  '         -^^^^^   ^ —Uvula 

_  Second  cervical  vertebra 

Faucial  tonsil- 
Posterior  pillar- 
Third  cervical  vertebra 


Fourth  cervical  vertebra 

Cuneiform  tubercle 
(Wrisberg) 

Fifth  cervical  vertebra 

Arytenoid  cartilage 

Sixth  cervical  vertebra 

(Esophagus 

Cricoid  cartilage 

Seventh  cervical  vertebra 


Epiglottis 

Hyoid  bone 

False  vocal  cord 

Thyroid  cartilage. 

Ventricle 

True  vocal  cord. 


Cricoid  cartilage 
Trachea 


Fig.  147. — Lateral  view  of  pharynx  and  larynx. 

nate  hypertrophy.  Not  only  does  the  mucous  membrane  of  the  inferior  turbinate 
bones  become  enlarged,  but  that  on  the  septum  likewise.  This  constitutes  hypertrophy 
or  thickeniyig  of  the  septum.  A  polypus  may  project  from  the  nasal  cavities  back- 
ward into  the  throat.  I  removed  a  very  large  one  by  pushing  it  with  the  finger  into 
the  pharynx  and  then  dragging  it  out  of  the  mouth. 

The  posterior  nares  are  quite  a  distance  anterior  to  the  edge  of  the  soft  palate, 
hence  it  is  extremely  difificult  to  make  appHcations  by  way  of  the  mouth.  A  much 
easier  way  is  to  make  them  through  a  tube  introduced  into  the  nose,  or  even,  as 
when  the  electrocautery  is  used,   without  a  protecting  tube. 

Eustachian  Tube. — On  each  side,  at  a  point  about  opposite  the  inferior  turbi- 
nals,  are  the  orifices  of  the  Eustachian  tubes  with  \\\q.  fossa  of  Rosenmiiller  above. 
The  Eustachian  tube  runs  from  the  upper  portion  of  die  pharynx  to  the  middle 
ear,  opening  just  behind  the  tympanic  membrane,  on  the  anterior  wall.     It  is  about 


THE    MOUT] 


119 


4  cm.  long,  2.5  cm.  being  cartilaginous  (pharyngeal  portion)  and  1.5  cm.  being 
bony.  At  the  junction  of  the  bony  and  cartilaginous  portions  the  lumen  is  slightly 
diminished,  forming  the  isthmus.     The  tube  runs  upward,  backward,  and  outward. 

The  mucous  membrane  of  the  throat  is  continuous  with  that  lining  the  tube  and 
tympanum,  therefore  inflammation  of  the  pharynx  travels  up  the  tube  and  affects  the 
middle  ear.     This  is  the  manner  in  which  earache  or  inflammation  and  suppuration 


Fig.  148  — Rhmoscopic  mirror  in  position.  A  view 
can  be  obtained  of  the  vault  of  the  pharynx  and  poste- 
ror  nares. 


Fig.  149- — Palpation  of  the  posterior  nares  and  phar- 
yngeal tonsil. 


of  the  middle  ear  is  produced.  This  also  explains  why  impairment  of  hearing  so 
often  accompanies  or  follows  sore  throat.  When  the  tube  is  in  a  healthy  condition, 
the  air  finds  free  access  to  the  ear,  in  swallowing,  sneezing,  etc.  This  is  readily 
demonstrated  by  closing  the  nostrils  and  swallowing,  when  the  pressure  of  air  out- 
side the  ear  drum  will  be  distinctly  felt.  -  When  inflammation  affects  the  lining  mem- 

'Vault  of  pharynx 
^/Superior  turbinate 


Septum 

Middle  turbinate 

Mouth  of  Eustachian  tube 

Inferior  turbinate 


Fig.  ISO. — View  of  posterior  nares  in  the  pharyngeal  mirror. 

brane  it  swells  and  blocks  up  the  tube  and  prevents  the  free  access  of  air  to  the  ear. 
If  the  swelling  is  not  too  great,  air  can  be  forced  from  the  throat  to  the  ear  by  three 
different  means.  The  distention  of  the  middle  ear  by  air  is  called  inflating  it.  The 
method  of  Valsalva  consists  in  holding  the  nostrils  and  mouth  shut  and  blowing. 
If  the  air  enters  the  middle  ear,  the  tympanic  membranes  will  be  felt  to  bulge 
outward.     The  method  of  Politzer  is  to  have  the  patient  hold  a  small  quantity  of 


I20 


APPLIED    ANATOMY. 


water  in  the  mouth.  The  nozzle  of  a  rubber  bag^  is  introduced  into  one  nostril, 
closing  both  nostrils  with  the  fingers  and  thumb  of  the  unengaged  hand.  On  telling 
the  patient  to  swallow,  the  bag  is  compressed  and  the  air  enters  the  Eustachian  tube. 
As  the  patient  swallows,  the  tensor  palati  muscle  opens  the  mouth  of  the  tube  and 
as  the  bag  is  compressed  the  air  rushes  up  the  tube.  Sometimes  the  vapors  of  ether, 
chloroform,  etc.,  are  used.     The  third  method  is  by  the  Eustachian  catheter. 

The  Eustachian  catheter  is  a  small,  hard  rubber  or  silver  tube,  slightly  bent 
at  the  extremity  and  long  enough  to  reach  from  the  anterior  nares  in  front  to  the 
posterior  wall  of  the  pharynx.     The  end  of  the  catheter  having  been  inserted  into 


iuperior  turbinate 


Sphenoidal  sinus 


Middle  turbinate 
Inferior  turbinate 

Pharyngeal  tonsil 
Fossa  of  Rosenmiiller 
Eustachian  lube 

Atlas 

Odontoid  process 
of  axis 


Body  of  axis 


Third  cervical  vertebra 


Fig.  isi. — Anteroposterior  frozen  section,  showing  a  lateral  view  of  the  phar>'nx  and  the  relation  of  the  various 

neighboring  structures. 

the  mouth  of  the  Eustachian  tube,  air  is  blown  in  with  the  Politzer  air-bag.  By 
means  of  a  rubber  tube  going  from  the  patient's  ear  to  the  surgeon's  ear,  the  air  can 
be  heard  entering  the  middle  ear. 

Introducing  the  Eustachian  Catheter.  —  In  introducing  the  Eustachian  catheter, 
the  tip  of  the  nose  is  to  be  tilted  upward  until  the  anterior  nares  are  raised  to  the 
level  of  the  floor  of  the  nose.  The  tip  of  the  catheter  is  then  passed  first  upward 
(Fig.  152),  then  along  the  floor  until  it  is  felt  to  pass  beyond  the  soft  palate  and  strike 
the  posterior  wall  of  the  pharynx  (Fig.  153).      It  is  usually  advised  to  enter  the 


THE    MOUTH    AND   THROAT. 


121 


catheter  in  a  vertical  position  and  then  change  to  a  horizontal  one  as  soon  as  the  beak 
passes  over  the  elevation  which  marks  the  separation  of  the  vestibule  of  the  nose  from 
the  interior.  If  this  method  is  used,  care  should  be  taken  to  keep  the  tip  of  the  catheter 
on  the  floor  of  the  nose  and  not  pass  it  up  in  the  region  of  the  middle  turbinate  bone. 

There  are  three  ways  of  introducing  the  beak  of  the  catheter  into  the  mouth  of 
the  tube  after  it  is  felt  touching  the  posterior  pharyngeal  wall.  The  first  is  to  with- 
draw the  beak  about  2  cm.  away  from  the 
wall  of  the  pharynx  and  then  turn  it  upward 
and  outward,  pushing  it  a  trifle  onward. 
The  second  way  is  to  turn  the  beak  directly 
outward  and  draw  it  forward,  when  it  can 
be  felt  passing  over  the  cartilaginous  open- 
ing of  the  tube.  The  third  way  is  to  turn 
the  beak  inward  and  draw  it  forward  until 
it  catches  behind  the  septum.  This  is  op- 
posite the  anterior  edge  of  the  mouth  of 
the  tube.  The  beak  is  then  rotated  down- 
ward and  then  upward  and  outward  into 
the  tube. 

Liquids  and  sprays  are  sometimes  in- 
jected into  the  ear  through  the  catheter; 
bougies  are  also  passed  into  the  tube  in  the 
same  manner  as  the  catheter  or,  if  flexible 
bougies  are  used,  they  are  passed  through 
the  catheter.  As  the  tip  of  the  bougie 
passes  into  the  bony  portion  of  the  canal, 
the  constriction  of  the  isthmus  can  be  felt 
2.5  cm.  up  from  its  mouth.  The  bougie 
should  not  be  passed  farther  than  3  cm. 
into  the  tube,  otherwise,  if  the  tympanum  is  entered,  the  ossicles  are  apt  to  be  injured. 

Openings  of  the  Mouth,  Larynx,  and  CEsophagus.^The  opening  of  the 
mouth  into  the  pharynx  is  sometimes  narrowed  from  cicatricial  contractions,  resulting 


Introducing  the  Eustachian  catheter,  first 
step. 


Fig.  153.- 


-Introducing  the  Eustachian  catheter, 
second  step. 


Fig.  154. — Introducing  the  Eustachian  catheter, 
third  step. 


from  ulcerative  processes  due  to  syphilis,  caustics,  etc.  There  is  rarely  obstruction 
downward,  so  that  these  patients  can  usually  swallow,  but  the  cicatrices  contract  the 
opening  upward,  and  the  soft  palate,  its  arches,  and  the  walls  of  the  pharynx  may  be 
all  bound  together  in  one  cicatricial  mass,  preventing,  as  I  have  seen,  all  respiration 
through  the  nose.  This  condition  is  an  exceedingly  difficult  one  to  remedy,  as  the 
contraction  tends  to  recur  even  after  the  most  radical  operations. 

The  opening  into  the  larynx  is   more  accessible  than  is  often  supposed.      On 
drawing  the  tongue  well  forward,  the  tip  of  the  epiglottis  can  be  seen.      If  a  long 


132 


APPLIED    ANATOMY. 


straight  tongue  depressor  is  used,  Kirstein  has  shown  that  in  many  patients  the 
arytenoid  cartilages  and  even  a  portion  of  the  vocal  cords  can  be  seen.  The  open- 
ing into  the  larynx  can  readily  be  felt  by  a  finger  introduced  into  the  mouth.  In  cases 
of  suffocation  from  a  foreign  body,  as  a  piece  of  meat,  it  is  usually  lodged  at  this 
point,  part  of  the  foreign  body  being  in  the  larynx  and  part  in  the  pharynx.  It  can 
readily  be  dislodged  by  the  finger,  as  I  have  done  in  impaction  of  meat,  the  result  of 
vomiting  in  ether  narcosis.  The  forefinger  should  be  thrust  its  full  length  into  the 
mouth  and  throat  and  swept  from  side  to  side.  The  obstructing  body  can  usually 
be  brushed  aside  and  brought  up  in  front  of  the  finger  into  the  mouth. 

The  opening  of  the  esophagus  is  in  a  line  with  the  long  axis  of  the  pharynx ;  it 
is  at  its  lower  end.  The  opening  of  the  larynx,  on  the  contrary,  is  more  on  its 
anterior  wall.  It  is  for  this  reason  that  when  an  oesophageal  tube  is  introduced,  either 
through  the  mouth  or  through  the  nose,  it  goes  down  into  the  oesophagus  and  does 
not  enter  the  larynx.      The  oesophagus  is  narrowest  at  this  point. 

The  pharyngeal  tonsil  stretches  across  the  posterior  wall  and  roof  of  the 
pharynx  from  the  opening  of  one  Eustachian  tube  to  that  of  the  other.     It  is  also 

'Pharyngeal  tonsi' 


Fossa  of  Rosenmiiller 
Eustachian  tube 

Supratonsillar  fossa 

Pterygomandibular  fold 
Plica  triangularis 

Anterior  pillar 
Faucial  tonsil 
Posterior  pillar 

Epiglottis 


Fig.  15  s. — Lateral  view  of  the  pharyngeal  region. 


known  as  LuschkcC  s  tonsil.  It  is  composed  of  lymphoid  tissue,  and  when  enlarged 
constitutes  the  disease  known  as  adenoids.  It  is  not  true  secreting  gland  tissue, 
though  it  contains  some  mucous  glands.  It  hangs  from  the  vault  of  the  pharynx  in  a 
more  or  less  lobulated  mass  and  when  large,  in  children,  obstructs  nasal  respira- 
tion. Mouth-breathing  results,  the  child  is  apt  to  snore  and  make  queer  sounds 
when  sleeping,  and  the  habit  of  keeping  the  mouth  open  causes  a  peculiar  expres- 
sion of  the  face  almost  pathognomonic  of  the  affection.  The  blood  supply  at  times 
is  abundant.  When  adenoids  are  present,  their  removal  is  usually  undertaken. 
This  is  done  by  introducing  an  instrument  either  through  the  nose  or  through  the 
mouth  and  scraping  them  off.  A  curette  is  used  for  this  purpose.  That  known  as 
'Gottstein's  consists  of  an  oval-shaped  ring  set  at  right  angles  to  a  long  shaft.  It  is 
introduced  through  the  mouth  and  up  behind  the  soft  palate.  It  is  then  pushed 
against  the  vault  of  the  pharynx  and  posterior  wall  and  drawn  downward  cutting 
and  scraping  the  adenoid  tissue  away.  A  much  smaller  ring  curette  set  on  a  long, 
delicate,  but  stiff  handle  may  be  used  through  the  nose  for  the  same  purpose.  In  using 
the  latter  instrument,  it  is  common  to  use  an  anaesthetic  and  operate  with  the  head 
in  a  hanging  position.  Free  bleeding  may  occur  from  this  operation.  To  control  it, 
injections  of  ice  water  or  a  strong  alum  solution  may  be  tried  or  gauze  may  be 
packed  behind  the  soft  palate  or  pushed  in  from  the  anterior  nares.     A  folded  pad  of 


THE    MOUTH    AND    THROAT. 


123 


gauze  may  be  attached  to  the  thread  of  a  Bellocq  cannula  and  the  pad  introduced 
as  is  done  in  plugging  the  posterior  nares.  A  curved  forceps  with  cutting  blades 
is  also  used  to  remove  this  growth. 

Fossa  of  Rosenmiiller. — This  is  the  depression  abo\e  and  behind  the  open- 
ings of  the  Eustachian  tubes.  The  walls  of  the  pharynx  are  weakest  at  this  point 
owing  to  the  superior  constrictor  muscle  not  coming  so  high  up.  Hernia  of  the 
mucous  membrane  sometimes  occurs  here.  When  the  beak  of  the  Eustachian  cath- 
eter fails  to  enter  the  mouth  of  the  tube  it  usually  enters  this  fossa. 

The  internal  carotid  artery  runs  up  the  neck  outside  of  the  pharynx  and 
opposite  the  space  between  the  posterior  arches  of  the  palate  and  the  posterior  wall 
of  the  pharynx.  It  is  from  i  to  2  cm.  behind  and  to  the  outer  side  of  the  tonsils. 
It  is  separated  from  the  cavity  of  the  throat  by  its  own  proper  sheath,  by  the  thin 
buccopharyngeal  fascia  covering  the  constrictor  muscles,  by  the  constrictor  muscles, 
the  pharyngeal  aponeurosis,  and  the  mucous  membrane.  As  the  tonsils  lie  between 
the  pillars  of  the  fauces,  in  opening  a  tonsillar  abscess  the  knife  is  not  carried  either 


^0^' 


Fig.  156.— Transverse  dissection  of  the  neck.    The  posterior  wall  of  the  pharynx  has  been  removed  and  the  vessels 
exposed.    The  internal  carotids  are  seen  to  be  abnormally  tortuous,  with  a  tendency  to  bulge  into  the  pharynx. 

behind  or  through  the  posterior  pillar  of  the  fauces.  It  is  practically  impossible  to 
wound  a  normal  internal  carotid  artery.  In  old  people  the  internal  carotid  sometimes 
becomes  lengthened  and  tortuous  in  the  same  manner  as  do  the  temporal  arteries.  In 
such  cases  the  artery  may  form  a  pulsating  swelling  behind  and  projecting  farther 
inward  than  the  edge  of  the  posterior  pillar.  This  I  have  once  seen.  It  may  be 
mistaken  for  a  true  aneurism,  as  it  pulsates  and  the  pulsation  is  readily  stopped  by 
pressure  on  the  common  carotid  on  the  outside  of  the  neck.  If,  however,  the  possi- 
Ijility  of  this  condition  is  borne  in  mind,  the  diagnosis  can  readily  be  made.  The 
pulsating  swelling  can  readily  be  seen  and  felt  with  the  finger  just  behind  the  posterior 
pillar  of  the  fauces. 

The  mucous  membrane  of  the  nasopharynx  is  ciliated  columnar;  that  of  the 
lower  portion  is  squamous.  It  contains  racemose  mucous  glands  and  follicles  or  crypts 
surrounded  by  lymphoid  tissue.  It  is  well  supplied  with  blood-vessels.  It  is  fre- 
quently affected  by  inflammation  or  pharyngitis.  When  the  follicles  are  markedly 
involved  they  can  be  seen  studded  over  the  posterior  wall  of  the  pharynx.  This 
constitutes  a  follicular  pharyngitis.  Not  infrequently  some  ulceration  may  be 
present,  forming  an  idceraiive  pharyngitis.  Infection  attacks  it,  as  in  diphtheritic 
pharyngitis.  Should  pus  or  pharyngeal  abscess  form  around  the  pharynx,  arising 
from  an  infection  from  the  oral  cavity,  the  pus  occupies  the  retropharyngeal  space 


124 


APPLIED   ANATOMY. 


between  the  buccopharyngeal  fascia  and  prevertebral  fascia.  Its  spread  upward  is 
limited  by  the  skull;  laterally  it  is  limited  by  the  sheath  of  the  carotid  vessels;  hence 
it  passes  downward  behind  the  oesophagus  and  may  enter  the  posterior  mediastinum. 
Foreign  bodies  may  become  lodged  at  the  lower  end  of  the  pharynx  and  at  the 
beginning  of  the  oesophagus.  As  this  is  about  15  cm.  (6  in.)  from  the  teeth,  it  is 
beyond  the  reach  of  the  finger.  Luckily,  this  is  below  the  opening  of  the  larynx  and 
the  need  for  immediate  relief  is  not  so  urgent. 


THE    LARYNX. 

The  larynx  extends  from  the  top  of  the  epiglottis  to  the  lower  edge  of  the 
cricoid  cartilage.  It  is  composed  of  the  three  large  cartilages — epiglottis,  thvroid, 
and  cricoid — and  three  pairs  of  small  ones — the  arytefioids,  the  cornicidcc  laryngis 
or  cartilages  of  Santoriui,  and  the  cuneiform  or  cartilages  of  Wrisberg. 

The  position  of  the  larynx  in  relation  to  the  spine  varies  according  to  age.  In 
the  infant  it  lies  opposite  the  second,  third,  and  fourth  cervical  vertebrae;  in  the  adult 


Epiglottis 


Greater  horn  of  hyoid  bone 


Lesser  horn 

Body  of  hyoid  bone 

Superior  comu 

Opening  for  superior  laryngeal 

nerve 


Thyrohyoid  membrane 
— ^Thyroid  cartilage 


Inferior  comu 
Cricothyroid  membrane 
Cricoid  cartilage 

Trachea 


Fig.  157. — Anterior  view  of  hyoid  bone  and  larynx. 

it  lies  opposite  the  fourth,  fifth,  and  sixth.  The  larynx  being  loosely  attached  \'aries 
in  relation  to  the  vertebrae  according  to  the  position  of  the  head,  so  that  the  anterior 
portion  of  the  cricoid  cartilage  may  be  opposite  the  seventh  cervical  vertebra  in  some 
positions. 

Epiglottis. — Usually  the  tip  of  the  epiglottis  lies  lower  than  the  dorsum  of  the 
tongue,  so  that  looking  into  the  mouth  it  is  not  seen;  it  may,  however,  be  brought 
into  view  by  depressing  the  base  of  the  tongue  and  drawing  it  forward  with  a  long 
tongue  depressor.  As  the  epiglottis  rises  above  the  level  of  the  hyoid  bone,  a  cut- 
throat wound  passing  above  that  bone  may  cut  its  tip  entirely  off.  In  viewing  the 
epiglottis  from  above  downward  it  is  seen  to  project  somewhat  backward  in  its  middle. 
This  is  visible  in  the  laryngoscopic  mirror  and  is  called  the  cushion  of  the  epiglottis. 

Running  forward  fiom  the  epiglottis  to  the  base  and  the  sides  of  the  tongue  are 
three  folds  of  mucous  membrane,  one  median  and  two  lateral,  called  the  glosso- 
epiglottic  folds.  These  form  four  fossae;  those  on  each  side  of  the  median  line  are 
called  the  vallecidce.  In  these  fossae  foreign  bodies,  such  as  fish-bones,  etc.,  may 
become  lodged.     They  are  readily  seen  by  the  laryngoscopic  mirror. 


THE  MOUTH  AND  THROAT.  125 

The  thyrohyoid  membrane  passes  between  the  hyoid  bone  above  and  the 
thyroid  cartilage  below  ;  crossing  it  is  the  hyoid  branch  of  the  superior  thyroid  artery. 
It  is  a  quite  small  vessel,  of  little  clinical  importance,  and  ordinarily  does  not  reach 
the  median  line. 

The  posterior  edge  of  this  membrane,  running  from  the  superior  cornu  of  the 
thyroid  cartilage  to  the  hyoid  bone,  is  called  the  thyrohyoid  ligament.  This  liga- 
ment has  a  small  cartilaginous  nodule  in  it,  the  cartilago  triticea.  Piercing  the 
membrane  on  its  side  are  the  internal  branches  of  the  superior  laryngeal  nerve 
and  the  superior  laryngeal  vessels.  The  external  branch  of  the  superior  laryngeal 
nerve  supplies  the  cricothyroid  muscle,  while  the  internal  is  the  ner\e  of  sensation 
of  the  larynx. 

Pharyngotoniy. — Sometimes,  in  order  to  remove  foreign  bodies  in  the  larynx  or 
oesophagus,  an  opening  is  made^;hrough  the  membrane  between  the  hyoid  bone  and 
thyroid  cartilage. 

Thyroid  Cartilage. — This  is  the  largest  cartilage  of  the  larynx  and  contains 
the  vocal  cords.     They  lie  immediately  behind  or  just  below   the  most  prominent 

^--Lesser  cornu 
Epiglottis^ i:  -    '  ^'^ 

Greater  cornu 


Body  of  hyoid  bone^ ^^  a»r»4_*r»^JHP^^^^t#^C*'"'''^80  triticea 

Thyrohyoid  membrane-  ,    ^^^  ^^^ 

'~~***i^l^^^t'       I      .„Jt^  jf — 'Supenot  cornu 

^  I 

Thyroid  cartilage 


^^  -Inferior  cornu 

Cricothyroid  membrane- 

Cricoid  cartilage 


Fig.  158. — Side  view  of  hyoid  bone  and  larynx. 

portion  of  its  anterior  edge,  commonly  called  "Adam's  apple."  Since  the  cartilage 
is  large  and  strong  and  as  age  advances  tends  to  calcify,  cut-throat  wounds,  while 
opening  the  cavity  within,  do  not  often  pass  entirely  through  the  cartilage.  This 
cartilage  may  be  fractured  by  violence.  This  is  often  fatal  on  account  of  the  blood 
flowing  into  the  trachea  and  lungs  below  or  on  account  of  oedema  of  the  lining  mucous 
membrane  causing  obstruction  of  the  breathing.  Thyrotomy  or  division  of  the 
thyroid  cartilage  in  the  median  line  is  sometimes  done  to  remove  foreign  bodies  or 
new  growths.  In  these  cases  the  voice  will  be  likely  to  be  impaired  by  the  interference 
with  the  vocal  cords. 

Cricothyroid  Membrane. — The  space  between  the  cricoid  and  thyroid  carti- 
lages is  small.  This  is  due  to  the  increase  in  width  of  the  cricoid  as  it  proceeds  back- 
ward. The  space  is  readily  felt  on  the  living  subject  between  the  thyroid"  above  and 
the  cricoid  beneath  ;  the  membrane  passes  between  them.  It  is  crossed  by  a  small 
branch  of  the  superior  thyroid  artery,  the  cricothyroid.  It  is  not  large  enough  to  cause 
serious  trouble.      Introducing  a  tube  through  this  membrane  constitutes  the  operation 


126 


APPLIED   ANATOMY. 


of  laryngotorny.  This  operation  is  but  seldom  performed.  The  space  is  too  small 
in  many  cases,  the  opening  is  not  made  sufficiently  low  and  it  is  too  close  to  the 
vocal  cords.  It  is  an  operation  of  emergency.  It  is  much  easier  to  make  a 
quick  opening  at  this  point  than  it  is  in  the  trachea  below,  as  it  is  more  superficial 
and  is  held  steady  in  place  by  the  cartilage  above  and  below  it.  Even  in  adults  the 
space  is  sometimes  too  small  to  introduce  a  tube  without  force  and  the  operation 
should  never  be  done  below  the  age  of  thirteen.  On  account  of  the  membrane  being 
nearer  the  surface  than  is  the  trachea,  a  shorter  tube  should  be  used.  Before  intro- 
ducing the  tube,  care  must  be  taken  that  the  mucous  membrane  has  been  thoroughly 
divided,  as  otherwise  the  tube  will  push  it  before  it  and  slip  between  the  mucous 
membrane  and  the  cartilage  and,  therefore,  not  enter  the  cavity  of  the  larnyx. 

Cricoid  Cartilage. — This  is  much  larger  posteriorly  than  anteriorly  and  fills 
the  space  between  the  posterior  edges  of  the  thyroid  cartilage.  Its  outside  diameter 
is  larger  than  that  of  the  trachea,  hence  it  can  readily  be  felt  and  forms  one  of  the 
most  important  landmarks  on  the  front  of  the  neck.      It  is  about  opposite  the  sixth 


Fig.  159. — Examining  the  interior  of  the  larynx  by  means  of  the  laryngoscopic  mirror. 

cervical  vertebra.  It  is  thick  and  strong  and  forms  a  complete  circle,  being  unhke 
the  tracheal  rings  in  this  respect.      It  is  rare  that  it  is  divided  in  operations. 

For  the  parts  concerned  in  tracheotomy  see  the  section  on  the  neck. 

Laryngoscopy. — The  interior  of  the  larynx  is  examined  by  means' of  a  small 
mirror,  i  to  3  cm.  in  diameter,  introduced  through  the  mouth  and  placed  just  below 
the  uvula  at  an  angle  of  a  little  more  than  45  degrees.  The  opening  of  the  larynx  is 
not  directly  beneath  the  mirror  but  slightly  anterior.  The  base  of  the  tongue  and 
lingual  tonsils,  the  glosso-epiglottic  folds  and  pouches,  and  the  epiglottis  can  be  seen 
in  front.  Posteriorly  one  sees  the  two  arytenoid  cartilages  capped  with  the  cartilages 
of  Santorini.  Between  the  arytenoids  is  the  commissiire  or  interarytenoid  space. 
To  the  front  and  outer  side  of  the  tip  of  the  arytenoid  cartilages  is  the  cartilage  of 
Wrisberg,  and  running  from  it  forward  are  the  aryepiglottic  folds.  To  the  outer 
side  of  the  aryepiglottic  fold  is  the  depression  called  the  sinus  pyr if ormis.  It  is  here 
that  congenital  cervical  fistulae  sometimes  open.  Near  the  middle  are  seen  the  two, 
white,  true  vocal  cords.,  and  to  the  outer  edge  of  these  are  seen  the  false  vocal 
cords.  Between  these  two  is  the  opening  of  the  ventricle  of  the  larynx.  The  rings 
of  the  trachea  can  readily  be  seen  and  not  infrequently  even  the  point  of  bifurcation 
of  the  trachea  opposite  about  the  second  rib. 


THE   NECK. 


127 


Diseases  of  the  Larynx. — Syphilis  affects  the  larynx  and  produces  ulcers. 
These  may  involve  almost  any  portion  but  usually  they  are  anterior,  involving  the 
epiglottis.  They  are  often  associated  with  syphilitic  manifestations  in  the  mouth. 
Tuberculosis  affects  the  posterior  portion  of  the  larynx  and  the  bulb-like  swellings  of 
the  arytenoids  are  almost  pathognomonic.  Ulcers  when  they  occur  are  most  marked 
posteriorly.  This  affection  is  associated  with  a  blanching  of  the  mucous  membrane 
of  the  mouth  and  the  presence  of  a  white  frothy  mucus,  which  will  lead  the  laryn- 
gologist  to  suspect  the  existence  of  the  disease  before  a  view  of  the  larynx  is  obtained. 

Laryngitis  of  a  simple  nature  produces  a  reddening  of  the  cords  and  a  swelling 
of  the  membrane  generally. 

In  cedema  of  the  larynx,  the  serous  effusion  puffs  up  the  loose  mucous  membrane, 
particularly  of  the  aryepiglottic  folds  and  epiglottis. 

Tumors  both  benign  and  malignant  affect  the  larynx  and  can  at  times  be  seen  to 
arise  from  the  vocal  cords. 

Paralysis  of  the  muscles  is  most  frequent  from  interference  with  the  recurrent 


Epiglottis 


Plica  ventricularis 
(false  vocal  cord) 


Ventriculus  laryngis 


Plica  vocalis  (true  vocal  cord) 

Tuberculum  cuneiformi 
(Wrisberg) 

Tuberculum  corniculatum 
(Santorini) 

Fig.  160. — View  of  the  larynx  as  seen-in  the  laryngeal  mirror. 

laryngeal  nerve.  This  nerve  supplies  the  abductor  muscles  and  when  paralyzed  the 
cords  tend  to  fall  together.  The  nerve  may  be  injured  in  operations  on  the  neck  or 
involved  in  cancer  of  the  thyroid  gland,  or  oesophagus,  or  in  aneurisms.  If  one  cord 
is  paralyzed,  the  voice  is  lost  temporarily,  and  when  it  returns,  it  is  changed  in  char- 
acter. Paralysis  of  both  nerves  does  not  cause  entire  loss  of  voice  because  the  cords  fall  to- 
gether, but  may  induce  suffocative  symptoms  ending  in  death.  Paralysis  of  the  left  vocal 
cord  is  believed  by  Fetterolf  and  Norris  to  be  due  to  compression  of  the  left  recurrent 
laryngeal  nerve  between  the  left  pulmonary  artery  and  the  aorta  or  the  aortic  ligament. 

THE  NECK. 

The  neck  supports  the  head.  It  is  a  pedestal  for  the  head,  and  is  long  in  pro- 
portion to  its  thickness;  the  apparent  object  of  this  being  to  elevate  the  head  and 
allow  it  to  be  moved  freely  in  different  directions.  The  animal  is  thus  better  enabled 
to  discover  its  enemies  and  to  guard  itself  against  them. 

The  various  structures  of  the  neck  are  mosdy  long,  running  between  the  head 
above  and  the  trunk  below.  This  is  the  case  with  the  spine,  the  air-  and  food-pas- 
sages, the  blood-vessels,  nerves,  and  even  some  muscles,  as  the  sternomastoid  and 
trapezius.  The  shorter  structures  are  either  the  component  parts  of  the  longer 
ones,  as  the  vertebrae  of  the  spine  and  the  rings  of  the  trachea,  or  are  separate 
organs  like  the  larynx,  thyroid,  and  submaxillary  glands.  The  presence  of  these 
latter  organs  is  not  dependent  on  the  length  of  the  neck  as  is  that  of  the  others.  In 
the  frog,  which  practically  has  no  neck,  the  head  being  placed  direcdy  on  the  trunk, 
there  sdll  exist  both  larynx  and  thyroid  gland.  In  the  singing  birds  the  vocal 
organ  or  syrinx  is  placed  in  the  chest  at  the  bifurcation  of  the  frachea.  As  regards 
the  cervical  spine,  blood-vessels,  air-  and  food-passages,  and  muscles,  these  evidently 
are  proportionate  to  the  length  of  the  neck.  In  the  batrachians  or  frogs  there  is  but 
a  single  cervical  vertebra ;  in  the  swan  there  are  twenty-five  cervical  vertebra,  and  in 
the  fishes  none.     In  man  of  course  the  number  of  cervical  vertebrae  remains  the  same. 


128  APPLIED    ANATOMY. 

seven,  no  matter  what  the  length  of  the  neck.  From  a  consideration  of  these  facts 
we  may  perhaps  state  that  the  neck  itself  is  a  subsidiary  organ,  not  of  any  great  im- 
portance in  itself,  but  rather  in  relation  to  some  other  portion  of  the  body — that 
portion  being  the  head.  It  is  the  stafi  which  supports  the  head  by  means  of  the 
cervical  spine  and  muscles. 

The  neck  contains  the  great  currents  of  blood  which  pass  to  and  fro  between 
the  head  and  trunk.  It  carries  the  air-  and  food -passages,  which  run  from  the  mouth 
above  to  the  lungs  and  stomach  below,  and  incidentally  it  contains  the  larynx,  the 
thyroid  and  submaxillary  glands,  and  some  lymphatic  nodes.  The  cerebrospinal 
nerves  of  all  the  body  below  the  head  pass  either  into  the  neck  or  through  it  to  the 
parts  beyond.  From  these  facts  it  becomes  evident  that,  while  the  neck  in  itself  may 
be  a  subsidiary  organ,  for  our  purposes  it  is  of  the  greatest  importance,  because 
interference  with  its  structure  either  by  disease  or  injury  —  operative  or  accidental  — 
may  destroy  the  brain  above,  by  interfering  with  its  nourishment,  or  the  body  below, 
by  interfering  with  the  vital  functions  of  respiration  and  nutrition,  or  may  paralyze  it 
by  destroying  the  conductivity  of  its  nerves.  The  construction  of  the  neck  then 
should  be  studied  with  a  view  of  explaining  or  understanding  the  diseases  and  injuries 
of  its  various  parts  and  the  operations  performed  for  their  relief. 

Injuries  and  Diseases  of  the  Neck. — Owing  to  its  exposed  position  the 
neck  is  frequently  injured  by  sprains,  contusions,  cuts,  and  punctured,  gunshot,  and 
all  sorts  of  wounds.  The  cervical  spine  may  become  dislocated  or  fractured  and  is 
frequently  the  seat  of  caries.  The  muscles  become  contracted,  producing  torticollis 
or  wry-neck.     They  may  sometimes  be  ruptured,  as  in  childbirth. 

The  arteries  are  affected  with  aneurism,  necessitating  their  ligation.  They  are 
also  divided  in  cut-throat  cases  and  wounds.  The  veins  are  of  importance  in  almost 
every  operation;  bleeding  from  them  is  dangerous  and  may  be  difficult  to  control. 

The  lymphatic  7iodes  are  more  numerous  than  elsewhere  in  the  body.  Frequently 
they  are  the  seat  of  tuberculous  or  sarcomatous  enlargement,  necessitating  their  re- 
moval. They  may  break  down  and  produce  wide-spreading  and  dangerous  abscesses, 
which  are  guided  in  their  course  by  the  fascias  ;  hence  a  knowledge  of  the  construc- 
tion of  the  deep  fascias  of  the  neck  enables  us  to  understand  them. 

The  submaxillary  and  thyroid  glands  are  the  seat  of  enlargement  and  foreign 
growths  requiring  the  performance  of  extensive  operations  for  their  extirpation. 
Enlargement  of  the  thyroid  gland  constitutes  the  disease  known  as  goitre.  It  is  also 
involved  in  exophthalmic  goitre  or  Graves'  s  or  Basedozv'  s  disease. 

The  ski7i  and  subcutaneous  tisstie  become  the  seat  of  inflammation  and  cellulitis. 
In  cases  of  wounds  this  cellular  inflammation  may  involve  the  structures  beneath  the 
deep  fascia;  this  occurs  in  cut-throat  and  gunshot  wounds. 

The  neck  is  also  liable  to  other  affections,  such  as  cysts  due  to  embryological 
defects.  Large  cysts  are  formed  called  hygromas,  also  sinuses  or  fistulae,  the  con- 
ge^iital fistulcE  of  the  neck.  The  larynx  may  be  the  seat  of  malignant  disease;  hence 
its  removal  is  undertaken.  The  operations  of  tracheotomy ,  laryngotomy,  and  cesoph- 
agotomy  are  also  at  times  necessary.  In  order  to  understand  these  various  affec- 
tions and  procedures  one  must  be  familiar  with  the  construction  of  the  neck,  what 
composes  it,  where  the  various  structures  lie  and  their  relation  to  one  another.  In 
order  to  utilize  this  knowledge  we  must  be  able  to  recognize  and  identify  the 
position  of  various  structures  before  the  skin  is  incised,  for  it  is  rarely  that  a  case 
presents  itself  with  a  wound  that  permits  a  view  of  the  deeper  structures;  hence  the 
importance  of  a  thorough  knowledge  of  its  surface  and  the  structures  capable  of 
being  recognized  through  the  skin. 

SURFACE  ANATOMY  OF  THE  NECK. 

For  convenience  of  study  we  may  consider  the  structures  in  the  median  line, 
and  those  regions  anterior  and  those  posterior  to  the  sternomastoid  muscle,  between 
it  and  the  trapezius.  The  posterior  portion  of  the  neck  will  be  described  in  the 
section  devoted  to  the  back. 

These  regions  or  triangles  are  simply  arbitrary  divisions,  made  for  conveni- 
ence of  description.     They  are  sometimes  spoken  of  in  reference  to  the  location 


I 


THE   NECK. 


129 


of  growths,  operative  incisions,  etc.  They  comprise  the  space  between  the  trapezius 
muscle  posteriorly,  the  median  line  anteriorly,  the  clavicle  below,  and  the  lower  jaw 
above. 

Viewed  from  in  front,  the  median  portion  of  the  neck  may  be  divided  into  three 
regions,  the  submental,  laryngeal,  and  tracheal. 

The  submental  region  extends  from  the  chin  to  the  lower  border  of  the  body 
of  the  hyoid  bone  ;  it  is  limited  laterally  by  the  anterior  belly  of  the  digastric  mus- 
cle on  each  side.  Ranula  and  other  sublingual  tumors  cause  a  bulging  in  this  region 
and  it  is  frequently  occupied  by  an  enlarged  lymphatic  node,  w^hich  at  times  sup- 
purates and  forms  an  abscess.  The  floor  of  the  space  is  formed  by  the  mylohyoid 
muscle  and  there  are  no  dangerous  structures,  so  that  no  hesitancy  need  be  had  in 
incising  abscesses  in  this  locality  nor  in  removing  diseased  lymph-nodes.  In  carci- 
noma involving  the  lower  lip  near  the  median  line  these  nodes  may  be  affected  and 


Anterior  belly  of  digastno 
Submaxillary  gland 

Hyoid  bone 
Thyrohyoid  membrane 

Thyroid  cartilage 
Cricothyroid  membrane 
Cricoid  cartilage 
Stemomastoid  muscle 

-Thyroid  gland 


Fig.  i6i. — Anterior  surface  of  the  neck. 

their  involvement  in  such  cases  should  always  be  looked  for.  The  submaxillary 
lymphatic  nodes  farther  outward  may  also  be  implicated.  The  tip  of  the  epiglottis 
projects  above  the  hyoid  bone  in  this  region. 

The  laryngeal  region  extends  from  the  under  surface  of  the  hyoid  bone  to  the 
lower  edge  of  the  cricoid  cartilage.  Laterally  it  is  limited  to  the  space  occupied  by 
the  larynx.  The  cricoid  cartilage  is  included  in  this  region  as  a  part  of  the  larynx. 
The  vocal  cords  are  just  beneath  the  most  prominent  part  of  the  thyroid  cartilage. 

The  tracheal  region  extends  from  the  lower  edge  of  the  cricoid  cartilage  to 
the  top  of  the  sternum.  Just  above  the  sternum,  between  the  sternal  origins  of  the 
stemomastoid  muscles,  is  the  suprasternal  notch  or,  as  it  is  called  by  the  Germans, 
the  Juguhim.      Laterally  the  region  is  limited  by  the  sides  of  the  trachea. 

There  are  seven  or  eight  rings  of  the  trachea  between  the  cricoid  cartilage  and 

the  top  of  the  sternum.      It  is  covered  partly  by  the  sternohyoid  and  sternothyroid 

muscles.      The  former  in  the  lower  half  of  their  course  pass  outv.ard,  leaving  a  space 

in  which  the  sternothyroid  muscles  are  seen.     The  sternohyoid  muscle  arises  from 

9 


I30 


APPLIED    ANATOMY. 


the  upper  and  outer  portion  of  the  manubrium,  the  sternoclavicular  ligament,  and  the 
inner  end  of  the  clavicle.  The  origin  of  the  sternothyroid  is  wider  than  that  of  the 
sternohyoid  and  is  lower  down.  It  arises  from  the  first  piece  of  the  sternum  near  the 
median  line,  below  the  sternohyoid,  and  from  the  cartilage  of  the  first  rib.  The  first 
ring  of  the  trachea  is  not  covered  by  any  important  structure.  The  second,  third, 
and  fourth  rings  are  covered  by  the  isthmus  of  the  thyroid  gland;  from  here  down 
the  inferior  thyroid  veins  may  lie  on  the  trachea  for  at  least  part  of  their  course.  The 
anterior  jugular  vein  may  exist  either  as  a  single  vein  in  the  median  line  or  to  one 
side  of  it,  or  one  may  pass  downward  on  each  side  of  the  median  line  with  a  communi- 
cating branch  from  one  to  the  other  crossing  the  median  line  in  the  suprasternal  notch. 
The  cricothyroid  artery,  a  small  branch  of  the  superior  thyroid,  may  cross  the  crico- 
thyroid membrane,  but  it  is  usually  too  small  to  cause  any  troublesome  bleeding. 

Structures  to  be  Felt  in  the  Median  Line. — On  passing  the  finger  down- 
ward from  the  symphysis  it  sinks  into  a  hollow,  on  crossing  which  the  hyoid  bone  is 


Anterior  belly  of  digastric 


Sternohyoid 

Anterior  belly  of 
omohyoid 


Submaxillary  triangle 


Superior  carotid  triangle 
Occipital  triangle 

Inferior  carotid  triangle 
Trapezius 

Posterior  belly  of  omohyoid 
•  Subclavian  triangle 


Fig.  162. — Showing  anterior  and  posterior  cervical  and  subsidiary  triangles. 


felt.  On  pressing  the  finger  into  this  hollow  it  rests  between  the  digastric  muscles 
on  each  side  and  the  mylohyoid  muscles  beneath.  Still  deeper  than  the  mylohyoid 
are  the  geniohyoid  and  geniohyoglossus  muscles  attached  to  the  genial  tubercles  on 
the  inner  side  of  the  mandible.  If  the  lymphatic  nodes  at  this  point  are  enlarged 
they  may  be  felt.    (Fig.  161.) 

The  hyoid  bone  can  usually  be  readily  felt  in  the  median  line.  If  it  is  not  easily 
discovered  in  the  median  line  it  can  be  felt  by  a  finger  and  thumb  placed  on  each 
side  of  the  neck  above  the  thyroid  cartilage. 

Passing  over  the  hyoid  bone  the  finger  then  sinks  into  the  space  between  it  and 
the  top  of  the  thyroid  cartilage.  This  space  is  bridged  by  the  thyrohyoid  mem- 
brane. Next  comes  the  thyroid  cartilage  or  "Adam's  apple."  It  can  readily  be 
seen  in  adult  males  and  thin  people,  but  in  the  fat  necks  of  women  and  children, 
though  it  can  still  be  felt,  it  often  cannot  be  seen.  The  finger  then  sinks  into  the 
space  between  the  thyroid  cartilage  above  and  the  cricoid  below.  They  are  con- 
nected by  the  cricothyroid  membrane,  over  which  runs  a  small  branch  (cricothyroid) 
of  the  superior  thyroid  artery. 


THE    NECK. 


131 


The  prominence  of  the  cricoid  cartilage  can  be  seen  in  thin  people  and  if  care- 
fully searched  for  can  be  felt  in  almost  all  cases.  It  is  opposite  the  sixth  cervical 
vertebra,  a  most  important  landmark.  From  the  cricoid  cartilage  down  to  the 
sternum  only  soft  structures  can  be  felt.  The  sternum  projects  forward  and  the 
trachea  inclines  backward  so  that  opposite  the  top  of  the  sternum  the  trachea  is  about 
2  cm.  behind  it.  The  distance  between  the  top  of  the  sternum  and  cricoid  cartilage 
in  an  adult  male  is  about  4.5  cm.  (i^  in.). 

THE  CERVICAL  TRIANGLES. 

On  viewing  the  neck  from  the  side  the  prominent  sternocleidomastoid  muscle 
with  its  thick  anterior  and  thin  posterior  edge  is  seen  to  divide  it  into  two  spaces, 
an  anterior  and  a  posterior.  They  are  called  the  anterior  and  posterior  cervical 
triangles. 


Submaxillary 
lymph-nodes 


Cervical  lymph- 
nodes 


External  jugular  vein 


^   iimaxillary 
gland 

Anterior  belly  of 
digastric 


Hyoid  bone 


Fig.  163.— Submaxillary  region,  superficial  structures.     (From  a  dissection,  lymph-nodes  enlarged  by  disease.) 


Anterior  Cervical  Triangle. 

The  anterior  cervical  triangle  has  for  its  anterior  side  the  median  line  of  the 
neck.  Its  posterior  side  is  the  anterior  edge  of  the  sternomastoid  muscle.  Its  upper 
side  is  the  lower  edge  of  the  mandible  from  the  symphysis  to  the  angle  and  thence 
across  to  the  mastoid  process.  The  anterior  triangle  is  further  divided  into  the  space 
above  the  digastric  muscle  called  the  submaxillary  triangle, — from  its  containing  the 
gland  of  that  name, — the  stiperior  carotid  triangle  above  the  anterior  belly  of  the 
omohyoid  muscle,  and  the  inferior  carotid  triatigle  below  the  omohyoid  muscle. 

The  submaxilliary  triangle  is  so  called  from  its  containing  the  submaxillary 
gland.      It  is  also  sometimes  called  the  lingual  triangle,  from  the  lingual  artery.      It 


132 


APPLIED    ANATOMY. 


has  as  its  upper  side  the  lower  edge  of  the  mandible  from  near  its  symphysis  around 
the  lower  edge  of  the  body  to  the  ramus  and  thence  in  a  straight  line  across  to  the 
mastoid  process.  Its  anterior  side  is  the  anterior  belly  and  its  posterior  side  is  the 
posterior  belly  of  the  digastric  muscle.  The  submaxillary  gland  can  usually  be  felt 
beneath  the  jaw.  Beneath  it  runs  the  facial  artery  to  pass  over  the  body  of  the 
mandible  in  front  of  the  anterior  edge  of  the  masseter  muscle.  The  gland  lies  on  the 
hyoglossus  and  mylohyoid  muscles,  which  form  the  floor  of  this  triangle.  It  is 
encased  in  a  sort  of  pocket  formed  by  a  splitting  of  the  deep  cervical  fascia.  The 
posterior  portion  of  this  fascia  runs  from  the  styloid  process  to  the  hyoid  bone  and  is 
called  the  stylohyoid  ligament. 

Lymphatic  nodes  lie  on  the  submaxillary  gland  and  in  carcinomatous  disease 
they  become  enlarged  and  then  can  be  readily  palpated.     In  operating  on  these 


Facial  artery 
Lingual  artery 

Occipital  artery 

External  jugular  vein 

Edge  of  sternomastoid 

muscle 

Internal  jugular  vein- 

Descendens  hypoglossi 
nerve 

External  carotid  arte 
Superior  thyroid  artery- 


Mylohyoid  muscle 
Hyoglossus  muscle 
Digastric  muscle 

Hypoglossal  nerve 

Tendon  of  digastric 


Fig.  164. — Deeper  structures  of  the  submaxillary  region,  especially  the  vessels. 


lymphatic  nodes  for  tuberculous  disease,  care  should  be  taken  to  distinguish  between 
them  and  the  submaxillary  gland.  The  tendon  of  the  digastric  muscle  does  not 
come  clear  down  to  the  hyoid  bone  but  the  loop  which  binds  the  two  together  is 
sometimes  a  centimetre  or  more  in  length.  The  lingual  artery  enters  the  sub- 
maxillary triangle  near  the  apex  of  the  angle  formed  by  the  tendon  of  the  digastric. 
It  crosses  beneath  the  posterior  belly  of  the  digastric  muscle  and,  particularly  if  the 
digastric  muscles  contract,  it  may  lie  close  to  the  tendon.  Frequently  the  search 
for  it  is  made  too  high  in  the  triangle  and  too  far  away  from  the  hyoid  bone. 
When  the  submaxillary  gland  is  lifted  from  its  bed  the  hypoglossal  nerve  is  seen 
beneath  lying  on  the  hyoglossus  muscle.  The  lingual  artery  lies  beneath  the  hyo- 
glossus muscle  and  the  muscle  is  cut  through  in  order  to  find  it.  The  submaxillary 
region  is  the  seat  of  Ludwig' s  atigina,  a  septic  inflammation  involving  the  cellular 


THE   NECK. 


135 


tissues  beneath  the  tongue  and  jaw  around  the  submaxillary  gland  and  the  upper 
portion  of  the  neck.  It  is  a  dangerous  affection  and  may  cause  death  not  only  by 
sepsis  but  also  by  oedema  of  the  larynx. 

Dr.  T.  Turner  Thomas  {An?ia/s  of  Surgery,  February  and  March,  1908),  has 
pointed  out  that  the  infection  passes  from  the  inside  of  the  mouth  to  the  submaxil- 
lary region  outside  by  following  the  connective  tissue  around  the  submaxillary  gland 
as  it  winds  around  the  posterior  edge  of  the  mylohyoid  muscle  through  the  opening 
existing  between  this  muscle  in  front  and  the  anterior  portion  of  the  middle  constrictor 
of  the  pharynx  behind. 

The  SUPERIOR  CAROTID  TRIANGLE  is  limited  posteriorly  by  the  sternomastoid 
muscle,  superiorly  by  the  posterior  belly  of  the  digastric,  and  inferiorly  by  the  anterior 
belly  of  the  omohyoid.  The  location  of  the  omohyoid  muscle  can  be  determined 
by  that  of  the  cricoid  cartilage,  as  the  muscle  crosses  the  common  carotid  artery 
about  opposite  that  point.  The  sternomastoid  muscle  can  be  both  seen  and  felt. 
It  is  attached  above  from  the  apex   of  the  mastoid    process  to  the  middle  of  the 


Mylohyoid 
Hypoglossal  nerve 

Digastric 
Submaxillary  gland  (su- 
perficial portion  removed) 

Hyoglossus 


Superior  constrictor 
Parotid  gland 

Styloglossus 
Middle  constrictor 
-  Digastric  (tendon) 
Stylohyoid  (tendoni 

Hyoid  bone 
Thyrohyoid 

Inferior  constrictor 
Omohyoid 

■  Sternomastoid 

■  Sternohyoid 

Fig.  165. — Submaxillary  region.  The  anterior  portion  of  the  submaxillary  gland  is  seen  winding  around 
and  beneath  the  posterior  edge  of  the  mylohyoid  muscle.  The  posterior  portion  of  the  gland  has  been  cut 
away.     The  posterior  belly  of  the  digastric  and  the  stylohyoid  muscles  have  also  been  removed. 


superior  curved  line  on  the  occipital  bone.  It  is  attached  below  by  a  sternal  head 
to  the  upper  anterior  part  of  the  first  piece  of  the  sternum,  and  by  a  clavicular  head 
to  the  inner  third  of  the  clavicle  on  its  superior  and  interior  border.  Its  action  will 
be  mentioned  in  discussing  wry-neck. 

Arteries. — The  carotid  arteries  and  their  branches  are  found  in  this  triangle. 
The  line  of  the  carotid  arteries  is  from  a  mid-point  between  the  mastoid  process  and 
the  angle  of  the  jaw  to  the  sternoclavicular  articulation.  The  line  of  the  sterno- 
mastoid muscle  is  from  the  mastoid  process  to  near  the  middle  of  the  upper  edge 
of  the  sternum.  Thus  the  carotids  are  internal  to  the  anterior  edge  of  this  muscle  above, 
behind  the  angle  of  the  jaw,  and  external  to  it  below.  The  common  carotid  at  its 
upper  portion — it  ends  opposite  the  upper  border  of  the  thyroid  cartilage — is  just 
about  at  or  close  to  the  edge  of  the  sternomastoid  muscle.  From  the  thyroid  car- 
tilage up  are  the  internal  and  external  carotids.  The  internal  lies  behind  and  to 
the  outer  side  of  the  external.  The  internal  gives  off  no  branches  until  it  reaches 
the  skull,  while  the  external  is  practically  all  branches.  Sometimes  the  external  and 
the  internal  carotids  are  covered  by  the  anterior  margin  of  the  sternomastoid  muscle. 
The  branches  of  the  external  carotid  are  the  superior  thyroid,  ascending  pharyngeal, 
lingual,  facial,  occipital,  posterior  auricular,  internal  maxillary,  and  temporal.    The 


134 


APPLIED    ANATOMY. 


superior  thyroid  or  the  ascending  pharyngeal  may  either  one  be  the  first  given  off 
by  the  external  carotid,  or  may  come  off  from  the  common  carotid  itself  just  before  its 
bifurcation. 

The  superior  thyroid  artery  is  given  off  in  the  interval  between  the  hyoid 
bone  and  upper  border  of  the  thyroid  cartilage.  It  gives  a  small  iiifrahyoid  brarich 
to  the  thyrohyoid  membrane,  also  a  superior  laryngeal  branch  to  the  inside  of  the 
larynx.  This  branch  pierces  the  thyrohyoid  membrane  in  company  with  the  superior 
laryngeal  nerve  to  reach  the  interior  of  the  larynx.  The  sternomastoid  branch,  to 
the  muscle  of  that  name,  comes  oft"  at  this  point  and  crosses  the  common  carotid  artery. 
It  is  of  some  importance  on  this  account  because  in  ligating  the  common  carotid 
artery  above  the  omohyoid  muscle  it  is  likely  to  be  cut  and  cause  bleeding.  Another 
branch  of  the  superior  thyroid  artery  is  the  cricothyroid.  It  is  small,  rests  on  the 
cricothyroid  membrane,  and  is  the  first  artery  liable  to  be  cut  in  an  incision  down  the 


Digastric 
Mylohyoid" 

Sublingual  gland 
Geniohyoid 

Submaxillary  ductr 
Submaxillary  gland 
Hypoglossal  nerve  -   .    Wf.  .-hJfci^ 't>'^     ^  ^1-^      ^--^  ^-— Lingual  nerve 

Superior  constrictor 
Styloglossus 
Parotid  gland 
Hyoglossus 
Middle  constrictor 
Stylohyoid  tendon 
Digastric  tendon 

•Thyrohyoid 

■  Inferior  constrictor 
■-Omohyoid 
■Btemothyroid 
.  Sternohyoid 

Fig.  i66. — Submaxillary  region — mylohyoid  muscle  cut  away  showing  the  sublingual  gland  and  anterior  portion 

of  submaxillary  gland. 

median  line.  Bleeding  from  it  is  not  apt  to  be  serious.  The  remainder  of  the 
superior  thyroid  artery  supplies  the  thyroid  gland. 

The  ascending  pharyngeal  is  a  long  slender  branch  that  comes  from  the 
under  side  of  the  main  trunk.  It  lies  on  the  superior  and  middle  constrictors  of  the 
pharynx  and  goes  clear  to  the  skull,  giving  off  some  meningeal  branches.  In  ligat- 
ing the  external  carotid  care  should  be  taken  not  to  include  this  vessel  in  the  ligature. 
It  also  gives  branches  to  the  soft  palate,  tonsil,  recti  capitis  antici  muscles,  and 
tympanum. 

The  lingual  is  given  off  just  below  the  greater  horn  of  the  hyoid  bone,  and 
passes  forward  beneath  the  hyoglossus  muscle  to  supply  the  tongue  and  sublingual 
tissues.    The  hypoglossal  nerve  lies  above  the  artery  and  on  the  hyoglossus  muscle. 

The  facial  comes  off  just  above  the  lingual  artery  or  often  in  a  common  trunk 
with  it.  It  passes  upward  and  forward  in  a  groove  in  the  under  surface  of  the  sub- 
maxillary gland  and  passes  over  the  edge  of  the  jaw  at  the  anterior  border  of  the 
masseter  muscle.     The  facial  vein  at  this  point  is  posterior  to  it. 

The  occipital  artery  comes  off  almost  opposite  the  facial.  It  passes  upward 
and  backward  between  the  mastoid  process  and  the  transverse  process  of  the  atlas, 


THE   NECK. 


135 


then  along  in  the  occipital  groove  beneath  the  origin  of  the  sternomastoid  muscle, 
the  splenius,  trachelomastoid,  and  digastric  to  make  its  appearance  a  Httle  to  the 
inner  side  of  the  middle  of  a  line  joining  the  mastoid  process  with  the  external  occip- 
ital protuberance. 

The  posterior  auricular  is  given  off  just  above  the  posterior  belly  of  the 
digastric  muscle  and  runs  backward  and  upward  on  it,  then  through  the  parotid 
•gland  and  up  between  the  external  auditory  meatus  and  the  mastoid  process.  In 
ligating  the  external  carotid  artery  with  a  view  of  preventing  bleeding  in  removing 
the  Gasserian  ganglion,  it  is  endeavored  to  place  the  ligature  just  above  the  digastric 
muscle  and  posterior  auricular  artery  in  order  to  preserve  the  blood  supply  of  the 


Temporal  artery 

Internal  maxillary 
artery 


External  carotid  artery 

Posterior  auricular 
artery 

Occipital  artery 

Hypoglossal  nerve 

Internal  jugular  vein 

Submaxillary  gland 

Facial  artery 

Internal  carotid  artery 

Lingual  artery 

Superior  laryngeal 

nerve 

Descendens  hypo- 

glossi  nerve 

Superior  thyroid  artery 
Sternomastoid  branch 


Fig.  167. — Carotid  arteries  and  branches. 

tissues  above  and  behind  the  ear.  The  internal  maxillary  and  the  temporal  arteries 
have  already  been  considered. 

Veins. — The  veins  found  in  and  near  the  superior  carotid  triangle  are  the  anterior 
and  internal  jugulars  and  their  branches.  A  small  portion  of  the  commencement  of  the 
external  jtigular  may  also  be  in  its  extreme  upper  angle. 

The  anterior  jugular  vein  begins  just  above  the  hyoid  bone  from  veins  in  the 
submaxillary  and  submental  regions.  It  lies  on  the  deep  fascia  and  passes  down  the 
neck  about  i  cm.  from  the  median  line,  then  just  above  the  sternum  it  turns  down  and 
out  under  the  sternomastoid  muscle  to  empty  into  the  external  jugular  or  subclavian. 
At  the  point  of  turning  it  sends  off  a  branch  across  the  median  line  to  the  vein  on  the 
opposite  side.  Thus  the  blood-current  can  pass  directly  across  the  neck  from  one 
external  jugular  vein  to  the  other.  Sometimes  there  is  another  communication 
between  the  two  anterior  jugulars  through  a  small  branch  crossing  just  above  or 


136 


APPLIED    ANATOMY. 


below  the  hyoid  bone.  Instead  of  two  anterior  jugular  veins  there  may  be  onefmt 
this  case  it  is  likely  to  go  down  the  median  line  of  the  neck  and  so  be  wounded  in 
tracheotomy.  It  receives  branches  from  the  inferior  thyroid  veins  and  hence  may 
bleed  freely.      It  has  no  valves. 

The  internal  jugular  vein  lies  to  the  outer  side  of  and  bulges  somewhat  an- 
terior to  the  carotid  arteries.  It  is  formed  by  the  junction  of  the  inferior  petrosal 
and  lateral  sinuses  at  the  jugular  foramen,  and  passes  downward  posterior  to  the 
internal  carotid  artery  and  soon  reaches  its  outer  side.  It  receives  the  facial,  lingual, 
pharyngeal,  superior  and  middle  thyroid,  and  sometimes  the  occipital  veins.  A  large 
communicating  branch  from  the  external  jugular  unites  either  with  the  facial  or  with 
the  internal  jugular,  so  that  a  wound  of  the  external  jugular  may  draw  blood  directly 
from  the  internal  jugular. 

These  tributary  veins  are  superficial  to  the  arteries  and  in  ligating  the  external 
carotid  artery  they  will  have  to  be  displaced.      The  internal  jugular  vein  is  sometimes 


Hyoglossus  muscle 

Hypoglossal  nerve 

Descendens  hypoglossi  nerve 

Superior  laryngeal  nerve 

Omohyoid  muscle 

Sternohyoid  muscle 
Sternothyroid  muscle 
Superior  thyroid  vein 


Inf.  thyroid  artery 
Recurrent  laryngeal 
nerve 
Sternothyroid 
and  hyoid 
muscles 
Inferior  thy- 
roid (thyroid-  - 
ea  ima)  vein 

Space  of  Bums- 


Omohyoid  muscle 
Middle  thyroid  vein 


Digastric  muscle 
Mylohyoid  muscle 
Facial  artery 
Facial  vein 

Submaxillary  gland 
Hyoid  bone 
Lingual  artery 

Internal  jugular  vein 
Superior  thyroid  artery 
Omohyoid  muscle 
Sternohyoid  muscle 
Anterior  jugular  vein 

Cricoid  cartilage 

Sternothyroid  muscle 


Stemomastoid 


I 


Fig.  i68. — Dissection  of  the  deep  structures  of  the  front  of  the  neck. 

excised  in  operations  for  enlarged  lymph-nodes  or  for  infective  thrombus.  It  is  not 
eO  large  above  the  facial  vein  as  below  that  point.  It  becomes  so  in\'olved  in  enlarge- 
ments of  both  tuberculous  and  carcinomatous  lymph-nodes  that  it  may  be  neces- 
sary to  excise  it  along  with  the  tumor.  Its  removal  does  not  give  rise  to  any  serious 
symptoms. 

It  becomes  thrombosed  by  the  extension  of  a  thrombus  from  the  transverse 
(lateral)  sinus,  which  in  turn  becomes  affected  by  the  extension  of  suppurative 
middle-ear  disease  through  the  medium  of  caries  of  the  bones.  When  the  internal 
jugular  is  thrombosed  it  is  evidenced  by  swelling,  redness,  and  tenderness  along 
the  anterior  border  of  the  stemomastoid  muscle  just  behind  the  angle  of  the  jaw. 
Bleeding  from  the  veins  in  this  region  is  particularly  dangerous  because  the  internal 
jugular  itself  is  so  large  and  having  no  valves,  will  bleed  both  from  the  side  towards 
the  heart  and  that  towards  the  head. 

The  veins  also,  which  are  tributary  to  it  in  this  region,  are  so  large  and  are 
wounded  so  close  to  the  main  trunk  that  the  blood  from  the  internal  jugular  itself 


THE    NECK.  137 

regurgitates.  The  walls  of  the  veins  are  thin  and,  if  the  fascias  happen  to  be  relaxed, 
fall  readily  together  and  thus  are  difficult  to  see,  and  are  so  adherent  to  the  fascias  as 
not  to  be  readily  seized.  The  surgery  of  this  region  requires  extreme  care  and  the 
avoidance  of  haste. 

Nerves. — Lying  between  the  internal  jugular  vein  and  the  internal  and  common 
carotid  arteries  is  the  pneicmogastric  or  tenth  nerve.  It  here  gives  off  the  superior 
laryngeal  nerve,  the  internal  branch  of  which  enters  the  larynx  through  the  thyro- 
hyoid membrane  to  endow  the  interior  of  the  larynx  with  sensation;  the  external 
branch  goes  to  supply  the  cricothyroid  muscle.  The  pneumogastric  nerve  is  fre- 
quently seen  in  operations  in  this  region.      Its  division  has  not  been  fatal. 

The  hypoglossal  nerve  winds  around  the  occipital  artery  and  goes  forward  on  the 
hyoglossus  muscle,  which  separates  it  from  the  lingual  artery.  The  descendens  hypo- 
glossi  filament  leaves  the  parent  nerve  as  it  winds  around  the  occipital  artery.  It  lies 
on  the  carotid  artery  in  the  form  of  a  loop  formed  by  the  addition  of  branches  from 
the  second  and  third  cervical  nerves.  As  it  descends  on  the  sheath  of  the  vessels  it 
gives  a  branch  to  the  anterior  belly  of  the  omohyoid  muscle.  The  loop  sends 
branches  to  the  sternohyoid,  sternothyroid,  and  posterior  belly  of  the  omohyoid,  and 
if  the  nerve  is  divided  paralysis  of  these  muscles  will  occur.  The  nerve  is  to  be 
pushed  aside  when  ligating  the  artery  and  not  included  in  the  ligature.  The 
superficial  branches  from  the  cervical  plexus  which  come  from  the  middle  of  the 
posterior  edge  of  the  sternomastoid  muscle  and  ramify  towards  the  median  line, 
are  nerves  of  sensation,  and  their  division  in  operative  work  causes  no  serious  symp- 
toms, hence  they  are  disregarded.  The  inframaxillary  branches  of  the  seventh  or 
facial  nerve  supply  the  platysma. 

Lymphatics. — The  lymphatics  are  composed  of  four  sets,  a  superficial  set  along 
the  anterior  border  of  the  sternomastoid  muscle,  a  deep  set  accompanying  the  great 
vessels,  a  submaxillary  set  around  and  on  the  submaxillary  gland,  and  a  set,  two  or 
more  in  number,  beneath  the  chin. 

The  S7ib maxillary  gland  itself  not  infrequently  enlarges  and  is  difficult  to  dis- 
tinguish from  an  enlarged  lymphatic  node.  All  these  glands  are  at  times  subjected 
to  operative  procedures.  Fig.  163  shows  the  submental,  submaxillary,  and  super- 
ficial set  of  lymphatics  enlarged,  as  w'ell  as  the  submaxillary  gland  itself.  It  is  taken 
from  a  tuberculous  subject. 

The  nodes  below  and  beiiind  the  jaw  become  enlarged  from  diseases  affecting 
the  tongue,  mouth,  and  throat  as  well  as  from  affections  of  the  face  and  scalp. 

The  INFERIOR  CAROTID  TRIANGLE  is  limited  posteriorly  by  the  lower  portion 
of  the  sternomastoid  muscle,  anteriorly  by  the  median  line  of  the  neck,  and  superiorly 
by  the  anterior  belly  of  the  omohyoid  muscle.  In  this  triangle,  or  reached  through  it, 
are  the  lower  portions  of  the  common  carotid  artery  and  internal  jugular  vein,  with 
the  pneumogastric  nerve  between.  Anteriorly  are  the  larynx,  trachea,  thyroid  gland, 
and  sternohyoid  and  sternothyroid  muscles.  The  carotid  artery,  jugular  vein,  and 
pneumogastric  nerve  lie  partly  in  the  triangle  but  rather  under  the  edge  of  the 
sternomastoid  muscle.  Operations  on  the  air-passages,  laryngotomy  and  tracheot- 
omy; on  the  thyroid  gland,  thyroidectomy;  and  ligation  of  the  common  carotid 
artery  and  removal  of  lymph-nodes  are  all  done  in  this  triangle.  The  superficial 
and  deep  lymphatics  accompany  the  vessels;  there  are  also  some  in  Burns' s  space 
above  the  sternum.  In  children,  instead  of  the  innominate  artery  ceasing  at  the 
sternoclavicular  articulation,  it  sometimes  rises  above  it  and  may  be  wounded  in 
operation  on  the  trachea.  The  thyroidea  ima  artery,  if  present,  will  lie  on  the 
trachea,  coming  up  from  the  innominate  or  directly  from  the  aorta. 

Posterior  Cervical  Triangle. 
The  posterior  cervical  triangle  has  as  its  base  the  middle  third  of  the  clavicle; 
its  anterior  side  is  the  posterior  edge  of  the  sternomastoid  muscle;  its  posterior  side 
is  the  anterior  edge  of  the  trapezius;  its  apex  is  at  the  point  of  junction  of  these  two 
muscles  at  the  superior  curved  line  of  the  occiput.  It  is  customary  to  divide  it  into 
two  triangles  by  the  posterior  belly  of  the  omohyoid  muscle.  The  upper  triangle  is 
large  and  is  called  the  occipital  triaiigle.  The  lower  triangle  is  small  and  is  called 
the  subclavian  triangle.  This  division  by  the  posterior  belly  of  the  omohyoid 
muscle  is  not  always  satisfactory.     The  muscle  runs  upward  and  inward  in  a  line 


138 


APPLIED    ANATOMY. 


from  about  the  junction  of  the  outer  and  middle  thirds  of  the  clavicle  to  a  variable 
distance,  up  to  2.5  cm.  (i  in.),  above  the  clavicle  at  the  anterior  edge  of  the  sterno- 
mastoid  muscle.  The  omoyhoid  muscle  has  its  lower  attachment  at  the  posterior 
edge  of  the  suprascapular  notch,  which  is  below  the  level  of  the  clavicle  and  its 
posterior  belly  is  sometimes  concealed  behind  the  clavicle  and  does  not  rise  above  it 
except  at  its  inner  extremity  beneath  the  sternomastoid  muscle.  It  is  rare  that  any 
distinct  triangle  is  formed,  hence  as  far  as  the  surface  markings  are  concerned 
there  is  often  no  subclavian  triangle.  Therefore  the  posterior  cervical  triangle  will 
be  considered. as  a  whole  and  not  divided. 

It  is  covered  by  the  skin,  beneath  which  is  the  subcutaneous  tissue,  which  at  its 
lower  portion  contains  the  fibres  of  the  platysma  muscle.  Its  floor  is  composed 
from  above  downward  of  the  splenius,  levator  scapulcc,  scalenus  posticus,  scalemis 
7nediiis,  and  scale?iiis  anticiis  muscles.  The  deep  fascia  of  the  neck  spans  the 
space  and  splits  anteriorly  to  enclose  the  sternomastoid  muscle  and  posteriorly  to 


Occipitalis  major  nerve 
Occipital  artery 
Occipitalis  minor  nerve 

Splenius  muscle 

Auricularis  magnus  nerve 

Superficial  cervical  nerve 

Levator  scapulae  muscle 

Spinal  accessory  nerve 

Trapezius 

Middle  scalene  muscle 

Posterior  scalene  muscle 
External  jugular  vein 

— ■—  Omohyoid  muscle 


Sternomastoid  muscle 
Anterior  scalene  muscle 

Phrenic  nerve.         \ 
Internal  jugular  vein 
Omohyoid  muscle 

Transverse  cervical 

artery 

Brachial  plexus 

Suprascapular  artery 

Subclavian  vein 

Subclavian  artery 

Fig.  169. — Dissection  of  the  posterior  cervical  triangle. 

enclose  the  trapezius.  The  space  contains  important  arteries,  veins,  nerves,  and 
lymphatics. 

External  Jugular  Vein. — Lying  on  the  deep  fascia  and  beneath  the  super- 
ficial fascia  and  platysma  is  the  external  jugular  vein.  This  begins  below  the  ear 
and  posterior  to  the  ramus  of  the  jaw,  being  formed  by  the  union  of  the  temporo- 
maxillary  and  posterior  auricular  veins.  It  passes  downward  and  slightly  backward 
on  the  surface  of  the  sternomastoid  muscle  to  its  posterior  border,  which  it  reaches  at 
about  the  middle  and  follows  down  until  about  a  centimetre  above  the  clavicle;  here 
it  pierces  the  deep  fascia  and  dips  behind  the  clavicular  origin  of  the  sternomastoid 
muscle  to  empty  into  the  subclavian.  It  has  one  pair  of  valves  about  4  cm.  above 
the  clavicle,  and  another  pair  at  its  point  of  entrance  into  the  subclavian.  They  do 
not  entirely  prevent  a  regurgitation  of  the  blood. 

The  external  jugular  vein  receives  the  posterior  external  jugular  vein,  and  the 
suprascapular  and  transverse  cervical  veins.  The  occipital  may  also  enter  into  it. 
The  veins  of  the  neck  are  exceedingly  irregular  in  their  formation  and  may  vary 
considerably.  The  external  jugular  is  readily  seen  through  the  skin,  it  may  be 
made  more  prominent  by  compressing  it  just  above  clavicle.      In  operations  in  this 


THE   NECK.  139 

region  of  the  neck  in  some  cases  it  is  necessary  to  divide  this  vein;  in  others  one 
may  be  able  to  a\oid  it,  at  all  events  it  should  be  recognized  before  the  incision  is 
made.  Behind  the  angle  of  the  jaw  there  is  usually  a  branch  communicating  with 
the  facial,  lingual,  or  internal  jugular  vein,  and  just  above  its  lower  extremity  it  is 
enlarged,  forming  the  part  called  the  sinus.  For  these  reasons,  if  the  vein  is  cut  low 
down  near  the  clavicle  or  high  up  near  the  angle  of  the  jaw  bleeding  is  liable  to  be 
free.  The  \-al\'es  are  not  competent  to  prevent  the  reflux  of  blood  and  it  therefore 
drains  the  large  internal  jugular  abo\'e  and  the  subcla\ian  below.  The  attachment 
of  the  vein  to  the  deep  fascia,  as  it  pierces  it  above  the  clavicle,  tends  to  keep  its 
lumen  open  when  the  vein  is  divided  and  favors  the  entrance  of  air  into  the  circula- 
tion. The  size  of  the  veins  in  the  posterior  triangle  varies  according  to  those  in  the 
anterior.  If  the  anterior  and  external  jugulars  are  large  the  posterior  and  internal 
jugulars  are  apt  to  be  small. 

Arteries. — The  arteries  in  the  posterior  cervical  triangle  are  the  subclavian,  the 
transverse  cervical,  and  sometimes  the  S2ipr as  capillar  when  it  runs  above  the  clavicle 
instead  of  behind  it.  The  line  of  the  subclavian  is  from  the  sternoclavicular  joint  to 
the  middle  of  the  clavicle.  It  rises  about  1.25  cm.  (^  in.)  above  the  clavicle.  The 
clavicular  origin  of  the  sternomastoid  muscle  covers  the  inner  third  of  the  clavicle  so  that 
the  subclavian  artery  is  only  visible  in  the  posterior  cervical  triangle  from  the  outer 
edge  of  this  muscle  to  the  middle  of  the  clavicle.  Both  the  suprascapular  and 
transverse  cervical  arteries  are  given  off  from  the  thyroid  axis,  which  arises  from  the 
first  portion  of  the  subclavian  just  internal  to  the  scalenus  anticus  muscle.  Therefore 
at  their  origin  they  are  both  considerably  above  the  level  of  the  clavicle,  but  as  they 
proceed  outward  they  incline  downward,  and  on  leaving  the  outer  edge  of  the  sterno- 
mastoid muscle  the  suprascapular  is  usually  behind  the  clavicle  while  the  transverse 
cervical  runs  parallel  to  it  and  a  short  distance  ( i  cm. )  above  it,  where  it  can  be 
felt  pulsating. 

The  posterior  belly  of  the  omohyoid  muscle  can  be  represented  by  a  line  drawn 
from  the  anterior  edge  of  the  sternomastoid  muscle  opposite  the  cricoid  cartilage, 
obliquely  down  and  out  to  the  junction  of  the  middle  and  outer  thirds  of  the  clavicle. 
It  is  superficial  to  the  transverse  cervical  artery  and  at  its  inner  end  is  above  it. 
These  arteries  and  their  accompanying  veins  will  be  encountered  in  operating  in 
these  regions  for  the  removal  of  lymphatic  nodes. 

Nerves.— The  nerves  in  the  posterior  cervical  triangle  are  the  spinal  accessory, 
branches  of  the  cervical  plexus,  and  the  brachial  plexus.  The  position  of  the  spinal 
accessory  is  important  because  it  is  frequently  encountered  in  operations  for  the 
removal  of  enlarged  lymphatic  nodes.  It  enters  the  under  surface  of  the  sternomastoid 
muscle  from  3  to  5  cm.  below  the  tip  of  the  mastoid  process  and  emerges  at  the  pos- 
terior edge  about  its  middle  or  a  little  above.  It  is  about  at  this  point  that  the 
external  jugular  vein  reaches  the  posterior  border  of  the  sternomastoid,  and  the  cervical 
plexus,  formed  by  the  anterior  divisions  of  the  four  upper  cervical  nerves,  reaches 
the  surface.  From  this  point  also  the  occipitalis  minor  runs  upward  along  the  posterior 
edge  of  the  sternomastoid  and  the  aiiricularis  viag?ius  runs  upward  over  the  sterno- 
mastoid direct  to  the  external  ear.  The  superficial  cervical  runs  directly  across  the 
muscle  towards  the  median  line  and  the  descending  branches — the  sternal,  clavicular, 
and  acromial — pass  down  beneath  the  deep  cervical  fascia  to  perforate  it  just  above  the 
clavicle  and  become  cutaneous.  Care  should  be  taken  not  to  mistake  them  for  the 
spinal  accessory.  Still  deeper  are  the  cords  of  the  brachial  plexus.  These  cords, 
sometimes  two,  at  others  three  in  number,  are  beneath  the  deep  fascia  and  lie  above 
the  subclavian  artery.  They  can  be  felt  and  in  a  thin  person,  if  the  head  is  turned  to 
the  opposite  side,  the  prominence  which  they  form  under  the  skin  can  even  be  seen. 

Lymphatics. — The  lymphatics  of  the  posterior  cervical  triangle  are  numerous 
and  being  often  enlarged  are  frequently  operated  on.  They  lie  along  both  the  outer 
side  of  the  internal  jugular  vein  and  under  the  posterior  edge  of  the  sternomastoid 
muscle,  which  they  follow  clear  up  to  the  base  of  the  skull.  They  also  follow  the  edge 
of  the  trapezius  muscle  and  lie  in  the  space  between  it  and  the  sternomastoid;  they 
extend  downward  under  the  clavicle  and  become  continuous  with  the  axillary 
lymphatics.  The  right  and  left  lymphatic  ducts  empty  into  the  venous  system  at 
the  junction  of  the  innominate  and  internal  jugular  veins.     That  on  the  left  side  is 


I40 


APPLIED   ANATOMY 


called  the  thoracic  duct ;  it  begins  as  the  receptaculum  chyli  on  the  body  of  tne 
second  lumbar  vertebra  and  is  about  45  cm.  (18  in.)  long.  It  drains  all  the  left  side 
of  the  body  and  the  right  as  far  up  as  and  including  the  lower  surface  of  the  liver. 

The  duct  on  the  right  side  is  called  the  right  lymphatic  djict ;  it  is  only  i  or  2 
cm.  in  length  and  drains  the  right  side  of  the  head  and  neck,  the  right  upper  ex- 
tremity, and  the  right  side  of  the  chest  as  far  down  as  and  including  the  upper  surface 
of  the  liver. 

TORTICOLLIS  OR  WRY-NECK. 

In  this  affection  the  head  and  the  neck  are  so  twisted  that  the  face  is  turned 
toward  the  side  opposite  the  contracted  muscle  and  looks  somewhat  upward.  It  is 
usually  caused  by  some  affection  of  the  sternomastoid  muscle.  It  is  not  always  the 
only  muscle  involved,  as  the  trapezius  and  others  may  likewise  be  affected.  It  is 
congenital  or  acquired.      In   the  congenital  cases  it  is  caused  by  an  injury  to  the 


Fig.  170. — Torticollis  or  wry-neck. 

Sternomastoid  muscle,  occurring  during  childbirth;  a  swelling  or  tumor  may  be 
present  in  the  course  of  the  muscle.  In  the  acquired  form  the  distortion  may  be 
more  or  less  permanent  and  may  be  due  to  caries  or  other  disease  of  the  spine.  In 
such  cases  it  is  evident  that  treatment  is  to  be  directed  to  the  diseased  spine  rather 
than  to  the  sternomastoid  muscle,  which  will  be  found  to  be  relaxed. 

Inflammation  of  the  lymph-nodes  of  the  neck  may  cause  the  patient  to  hold  the 
head  and  neck  in  a  distorted  position.  The  wry-neck  in  this  case  will  disappear  as 
the  cause  subsides.  Rheumatic  affections  of  the  neck  are  a  common  cause,  and  the 
sternomastoid  muscle  may  then  become  contracted  and  require  division.  In  rare 
instances  a  nervous  affection  causes  a  spasmodic  torticollis.  The  persistent  move- 
ments render  this  a  very  distressing  affection,  and  to  relieve  it  not  only  has  the 
sternomastoid  but  also  the  trapezius  been  divided,  and  even  the  spinal  accessory  and 
occipital  nerves  have  been  excised. 

Division  of  the  sternomastoid  muscle  should  be  done  by  open  and  not  by  sub- 
cutaneous incision.  The  sternal  origin  of  the  sternomastoid  muscle  is  a  sharp,  dis- 
tinct cord,  but  its  clavicular  origin  is  a  broad,  thin  band  extending  outward  a  third  of 
the  length  of  the  clavicle.  An  incision  2  or  3  cm.  or  more  in  length  is  made  over 
the  tendon  and  the  bands  are  to  be  carefully  isolated  before  being  divided.  The 
structure  most  important  to  avoid  is  the  internal  jugular  vein.  It  lies  close  behind 
the  sternal  origin  of  the  muscle  and  great  care  must  be  taken  to  avoid  it.  In  one 
case   in  which  it  was  accidentally  wounded  it  was  necessary  to  ligate  it.     As  the 


THE    NECK.  141 

deep  fascia  of  the  neck  splits  to  enclose  the  sternomastoid  muscle  it  is  opened  by 
the  operation  and  infection  has  caused  in  such  cases  wide-spread  phlegmonous 
inflammation. 

ARTERIES   OF   THE   NECK.— LIGATION. 

Carotid  and  Subclavian  Arteries  and  Branches.  —  Both  these  arteries  are 
affected  at  times  with  aneurisms,  necessitating  their  ligation.  Ligation  of  the  main 
trunks  or  their  branches  is  also  required  in  various  operations  on  the  head,  as  in  re- 
moval of  the  Gasserian  ganglion  or  maxilla,  or  excision  of  the  tongue,  thyroid  gland, 
etc.  The  communication  between  the  arteries  on  the  two  sides  of  the  body  is  quite 
free,  as  also  is  that  between  the  arteries  above  and  those  lower  down.  For  this 
reason  bleeding  from  the  distal  end  of  a  cut  artery  will  be  almost  as  free  as  from  its 
proximal  end.  The  various  branches  of  the  external  carotid  anastomose  across  the 
median  line  of  the  body.  The  vertebrals  communicate  above  through  the  basilar. 
The  internal  carotids  communicate  through  the  anterior  cerebral  and  anterior  com- 
municating and  with  the  basilar  through  the  posterior  communicating  and  posterior 
cerebral.  Between  the  parts  above  and  those  below  we  have  the  superior  thyroid 
anastomosing  with  the  inferior  thyroid  branch  of  the  thyroid  axis  from  the  subclavian 
artery.  The  princeps  cervicis,  a  branch  of  the  occipital,  anastomoses  with  the  as- 
cending cervical  branch  of  the  inferior  thyroid,  the  transverse  cervical  of  the  thyroid 
axis,  and  the  profunda  cervicis  from  the  superior  intercostal.  These  free  communi- 
cations enable  the  surgeon  to  ligate  to  any  extent  without  incurring  the  risk  of  gan- 
grene. The  line  of  the  carotid  arteries  is  from  a  point  midway  between  the  mastoid 
process  and  the  angle  of  the  jaw  to  the  sternoclavicular  articulation.  At  the  upper 
iDorder  of  the  thyroid  cartilage  the  common  carotid  divides  into  the  internal  and  ex- 
ternal carotids;  this  is  opposite  the  fifth  cervical  vertebra. 

Common  Carotid  Artery. — This  lies  on  the  longus  colli  muscle  and  a  small 
portion  of  the  rectus  capitis  anticus,  which  separate  the  artery  from  the  transverse 
processes  of  the  vertebrae.  The  artery  can  be  compressed  against  the  vertebrae  and 
its  pulsations  stopped  by  pressing  backward  and  slightly  inward.  It  is  superficial  in 
the  upper  portion  of  its  course  but  becomes  deeper  as  it  approaches  the  chest.  The 
anterior  tubercle  of  the  transverse  process  of  the  sixth  cervical  vertebra  is  called 
Chassaignac'  s  tubercle.  It  is  about  opposite  the  cricoid  cartilage.  It  is  one  of  the 
guides  to  the  artery.  The  omohyoid  muscle  crosses  the  artery  opposite  the  cricoid 
cartilage  and  just  above  it  is  the  site  of  election  for  ligation. 

Ligation  of  the  Common  Carotid  Artery. — In  making  the  incision,  which  should 
be  5  or  6  cm.  long,  it  should  be  laid  along  the  anterior  edge  of  the  sternomastoid 
muscle  with  its  middle  opposite  to  or  a  little  above  the  level  of  the  cricoid  cartilage. 
This  incision  may  be  a  little  anterior  to  the  direct  line  of  the  artery  as  given  from 
midway  between  the  angle  of  the  jaw  and  mastoid  process  to  the  sternoclavicular 
articulation.  This  is  because  the  muscle  bulges  forward  and  overlaps  and  hides  the 
artery.  The  artery  is  beneath  its  edge.  On  cutting  through  the  superficial  fascia  and 
platysma  the  deep  fascia  is  reached,  some  small  veins  perhaps  being  divided  in 
so  doing.  The  deep  fascia  is  divided  along  the  edge  of  the  sternomastoid  muscle, 
which  is  then  pulled  outward.  Beneath  it  and  running  obliquely  across  the  lower 
portion  of  the  wound  is  the  omohyoid  muscle.  It  is  recognized  by  the  direction  of 
its  fibres,  they  being  more  or  less  transverse  or  oblique.  Sometimes  a  small  artery, 
the  sternomastoid  branch  of  the  superior  thyroid,  crosses  the  common  carotid  just 
above  the  omohyoid  muscle.  The  artery  is  also  crossed  by  veins.  The  lingual, 
superior,  and  middle  thyroid  veins  all  pass  over  it  to  enter  the  internal  jugular. 
The  middle  thyroid  vein  may  be  above  or  just  below  the  omohyoid  muscle. 
These  vessels  all  pass  transversely  across  the  artery  and  beneath  the  deep  fascia. 
The  artery  lies  in  a  separate  sheath  to  the  inner  side  of  the  jugular  vein.  In  the 
living  body  it  is  to  be  recognized  by  its  pulsations.  The  vein  being  filled  with  blood 
may  overlap  the  artery.  Veins  are  readily  emptied  of  their  blood  by  pressure  on 
the  parts  during  the  operation;  hence  if  the  vein  happens  to  be  collapsed  it  may  not 
be  recognized  and  is  liable  to  be  wounded.  Therefore  in  examining  for  the  artery  see 
that  the  pressure  from  the  retractors  or  other  sources  does  not  obstruct  the  flow  of 


142  APPLIED    ANATOMY. 

blood  through  the  jugular  vein.  Running  down  on  the  anterior  surface  of  the 
artery  is  the  descendens  hypoglossi  nerve.  If  seen  it  should  be  pushed  aside.  It 
supplies  the  sternohyoid,  sternothyroid,  and  both  bellies  of  the  omohyoid  muscles. 
The  pneumogastric  nerve  lies  posteriorly,  between  the  artery  and  the  vein.  Care 
will  be  necessary  to  avoid  including  it  in  the  ligature.  The  ligature  is  to  be  carried  from 
the  outer  to  the  inner  side,  the  needle  being  passed  between  the  vein  and  the  artery. 
Ligation  of  the  Common  Carotid  Artery  Below  the  Omohyoid  Mnscle.—T\^^-3X\.^x:y 
below  the  omohyoid  muscle  becomes  deeper  and  less  accessible.  The  sternomastoid 
muscle  overlaps  it  and  is  less  easily  displaced.  The  sternohyoid  and  sternothyroid 
muscles  likewise  tend  to  encroach  on  it  and  have  to  be  drawn  inward.  The  internal 
jugular  vein  and  carotid  artery  diverge  as  they  descend,  so  that  at  the  level  of  the 
sternoclavicular  joint  they  are  separated  2.5  cm.  In  this  interval  the  first  portion 
of  the  subclavian  artery  shows  itself.  The  anterior  jugular  vein  will  probably  be 
encountered  along  the  edge  of  the  sternomastoid  muscle,  and  near  the  omohyoid 


Sternomastoid  artery 
Common  carotid  artery 
Descendens  hypoglossi  nerve 
~"  Internal  jugular  vein 
Sternomastoid  muscle 
Omohyoid  muscle 

Fig.  171. — Ligation  of  the  common  carotid  artery. 

muscle  the  artery  will  be  crossed  by  the  middle  thyroid  vein.  Still  lower  it  may  be 
that  the  inferior  thyroid  will  be  encountered.  Posterior  to  the  carotid  artery  is  the 
inferior  thyroid  artery,  coming  from  the  thyroid  axis  and  going  to  the  thyroid  gland, 
and  winding  around  from  posteriorly  to  the  inner  side  is  the  recurrent  laryngeal 
nerve.      The  ligating  needle  is  to  be  passed  from  without  inward. 

Collateral  Circulation  After  Ligation  of  the  Commofi  Carotid  Aj'tery. — When 
the  common  carotid  has  been  tied  the  blood  reaches  the  parts  beyond  from  the 
branches  of  the  carotid  of  the  opposite  side  and  from  the  subclavian  artery  of  the 
same  side.  The  branches  of  the  external  carotid  anastomose  across  the  median  line. 
This  is  particularly  the  case  with  the  superior  thyroid  and  facial.  The  internal 
carotids  communicate  by  means  of  the  circle  of  Willis.  From  the  subclavian  the 
vertebral  artery  communicates  by  means  of  the  basilar  with  the  circle  of  Willis. 
The  thyroid  axis  by  its  inferior  thyroid  branch  communicates  with  the  thyroid 
arteries  of  the  opposite  side.  An  ascending  branch  of  the  inferior  thyroid  as  well  as 
one  from  the  transverse  cervical,  also  from  the  thyroid  axis,  anastomose  with 
branches  of  the  princeps  cervicis,  which  is  a  descending  branch  of  the  occipital. 


THE    NECK. 


143 


Finally  the  superior  intercostal,  which,  like  the  vertebral  and  thyroid  axis,  is  a 
branch  of  the  first  portion  of  the  subclavian,  through  its  profunda  cervicis  branch 
anastomoses  with  a  deep  descending-  branch  of  the  princeps  cervicis  (Fig.  172). 

The  Internal  Carotid  Artery. — The  internal  carotid  Hes  posterior  and  to 
the  outer  side  of  the  external.  It  gi\es  off  no  branches  in  the  neck.  Entering  the 
skull  through  the  carotid  canal,  in  the  apex  of  the  petrous  portion  of  the  temporal 
bone  and  directly  below  and  to  the  inner  side  of  the  Gasserian  ganglion,  it  passes 
through  the  inner  side  of  the  caver?ioHS  sm/ts  and  at  the  anterior  clinoid  processes  it 
bends  up  to  divide  into  the  anterior  and  middle  cerebrals.  Before  its  division  it 
gives  off  the  posterior  comtminicating  artery,  the  anterior  choroid  artery  to  supply 
the  choroid  plexus  in  the  lateral  ventricles,  and  the  ophthalmic  artery.     The  internal 


Temporal 

Posterior  auricular 

Occipital 

Princeps  cervicis 

Superficial  branch 

Deep  branch 

Internal  carotid 


Transverse  cervical 
Suprascapular 


Transverse  facial 
Internal  maxillary 

Ascending  pharyngeal 
Facial 

Lingual 

External  carotid 
Superior  thyroid 


Inferior  thyroid 

Common  carotid 

Vertebral 
Thyroid  axis 
Innominate 


Superior  intercostal 


Subclavian 


Fig.  172. — Collateral  circulation  after  ligation  of  the  common  carotid  artery. 

carotid  artery  in  the  neck  is  normally  straight,  but  sometimes,  particularly  in  elderly 
persons,  it  is  tortuous.  This  may  then  be  mistaken  for  aneurism.  It  lies  about  2  cm. 
posterior  and  a  litde  to  the  outer  side  of  the  tonsil.  As  the  pharynx  is  the  side  of 
least  resistance,  when  the  vessel  becomes  tortuous  it  bulges  into  it,  and  on  examina- 
tion through  the  mouth  a  pulsating  swelling  can  be  distinctly  seen  in  the  pharynx 
just  posterior  to  the  tonsil.  The  finger  introduced  can  feel  the  pulsations,  and 
pressure  on  the  carotid  in  the  neck  below  causes  the  pulsations  to  cease.  Thus  the 
character  of  the  pulsating  swelling  can  be  recognized.  This  artery  is  rarely  ligated, 
but  if  it  is  desired  to  do  so  it  can  readily  be  reached  through  an  incision  6  or  7  cm. 
long  behind  the  angle  of  the  jaw.  Aneurism  or  wounds  may  necessitate  its  ligation. 
At  its  commencement  it  is  comparatively  superficial,  but  as  it  ascends  it  gets  quite 
deep,  passing  beneath  the  digastric  and  stylohyoid  muscles.  It  should  therefore  be 
ligated  below  the  angle  of  the  jaw  and  not  over  3  cm.  from  its  origin  at  the  upper 


144 


APPLIED    ANATOMY. 


border  of  the  thyroid  cartilage.  It  will  be  necessary  to  push  the  sternomastoid 
muscle  posteriorly,  as  its  anterior  margin  ox'erlies  the  vessel.  The  internal  jugular 
vein  is  to  its  outer  side  and  between  the  two  and  posterior  is  the  pneumogastric 
nerve.  The  sympathetic  7ierve  lies  behind  it  but  is  separated  by  a  layer  of  fascia  and 
is  not  liable  to  be  caught  up  in  passing  the  aneurism  needle.  The  lingual,  facial, 
and  laryngeal  veins  may  be  encountered  and  are  apt  to  cause  trouble.  They  will 
have  to  be  held  aside  or  ligated  and  divided.  The  ascending  pha?yngeal  artery  may 
lie  close  to  the  internal  carotid  and  care  should  be  taken  not  to  include  it  in  the 
ligature.      The  needle  is  to  be  passed  from  without  inward. 

The  External  Carotid  Artery. — Of  recent  years  the  external  carotid  artery 
has  been  ligated  far  more  often  than  formerly,  as  it  was  customary  to  ligate  the 
common  carotid  instead.  The  external  carotid  runs  from  the  upper  border  of  the 
thyroid  cartilage  to  the  neck  of  the  mandible.  It  supplies  the  outside  of  the  head, 
face,  and  neck.  These  parts  are  the  seat  of  various  operations  for  tumors,  especially 
carcinoma  of  the  mouth  and  tongue,  diseased  lymph-nodes,  and  other  affections,  and 


Facial  artery 
Lingual  artery, 

Greater  comu  of 
hyoid  bone 
Superior  laryn- 
geal nerve 
Ext.  carotid  artery 

Superior  thyroid 
artery 


Stylohyoid  muscle 

Digastric  muscle 

Occipital  artery 

Hypoglossal  nerve 

Descendens  hypoglossi 

nerve 

Internal  carotid  artery 


Internal  jugular  vein 
Superior  thyroid  vein 
Sternomastoid  artery 
Common  carotid  artery 

"Fig.  173. — Ligation  of  external  carotid  artery  and  its  branches. 

the  external  carotid  and  its  branches  are  not  infrequently  ligated  in  order  to  cut  off 
their  blood  supply. 

In  extirpation  of  the  Gasserian  ganglion,  hemorrhage  has  been  such  an  annoying 
and  dangerous  factor  that  a  preliminary  ligation  or  compression  (Crile)  of  the 
external  carotid  is  frequently  resorted  to.  This  artery  may  also  be  ligated  for 
wounds,  resection  of  the  upper  jaw,  hemorrhage  from  the  tonsils,  and  angiomatous 
growths  affecting  the  region  which  it  supplies. 

Unlike  some  other  arteries  the  external  carotid  sometimes  seems  to  have  no 
trunk,  consisting  almost  entirely  of  branches.  Therefore  in  ligating  it  one  should 
not  expect  to  find  a  big  artery  the  size  of  the  internal  carotid,  but  often  one  only  half 
as  large.  The  branches  of  the  external  carotid  artery  are  the  superior  thyroid,  lin- 
gual, and  facial,  which  proceed  anteriorly  toward  the  median  line  ;  the  occipital 
and  posterior  auricular,  which  supply  the  posterior  parts  ;  the  ascending  phary^igeal, 
which  comes  off  from  its  deep  surface  and  ascends  to  the  base  of  the  skull  ;  and 
the  temporal  and  internal  inaxillajy  arteries,  which  are  terminal.  It  is  ligated  either 
near  its  commencement  just  above  the  superior  thyroid  artery  or  behind  the  angle 
of  the  jaw  above  the  digastric  muscle. 

Ligation  of  the  External  Carotid  Aj'tery  above  the  Superior  Thyroid. — At  its 
commencement  at  the  upper  border  of  the  thyroid   cartilage  the  artery  is  quite 


THE    NECK 


MS 


superficial,  being  covered  by  the  skin,  superficial  fascia,  platysma,  deep  fascia,  and 
overlying  edge  of  the  sternomastoid  muscle.  It  is  to  be  reached  through  an  incision 
5  cm.  in  length  along  the  anterior  edge  of  the  sternomastoid  muscle  in  a  line  from 
the  sternoclavicular  joint  to  midway  between  the  angle  of  the  jaw  and  the  mastoid 
process.  The  middle  of  the  incision  is  to  be  opposite  the  thyrohyoid  membrane. 
The  bifurcation  of  the  common  carotid  artery  is  an  important  landmark. 

The  superior  thyroid  artery  is  given  off  at  the  very  commencement  and  some- 
times even  comes  from  the  common  carotid  just  below.  The  ascending  pharyngeal 
is  the  next  branch,  about  i  cm.  above  the  superior  thyroid.  It  comes  off  from  the 
deep  surface  of  the  artery  ;  almost  opposite  to  it  and  in  front  is  the  lingual.  It  will 
thus  be  seen  that  the  distance  between  the  lingual  and  the  superior  thyroid,  where 
the  ligature  is  to  be  placed,  is  quite  small.  The  superior  thyroid  is  about  opposite 
the  upper  border  of  the  thyroid  cartilage,  while  the  lingual  is  opposite  the  hyoid 
bone.  Beneath  the  artery  is  the  superior  laryngeal  nerve,  but  it  is  not  liable  to  be 
caught  up  by  the  needle  in  passing  the  ligature  because  it  lies  fiat  on  the  constrictors 
of  the  pharynx  and  is  apt  to  be  a  little  above  the  site  of  ligation. 

The  veins  are  the  only  structures  liable  to  cause  trouble.  They  are  superficial 
to  the  arteries.  On  account  of  their  irregularity  more  may  be  encountered  than  is 
expected.  The  superior  thyroid  and  lingual  veins  both  cross  the  artery  to  empty 
into  the  internal  jugular.  The  facial  vein  is  also  liable  to  be  met,  as  the  facial  artery 
frequently  springs  from  a  common  trunk  with  the  lingual.  The  communicating 
branch  between  the  facial  and  external  jugular  vein  is  another  one  that  should  be 
anticipated.  These  veins,  when  it  is  possible,  are  to  be  hooked  aside;  otherwise 
they  are  to  be  ligated  and  cut.  Great  care  should  be  taken  not  to  mistake  a  vein 
for  the  artery.  It  might  appear  an  easy  matter  to  readily  recognize  the  artery  and 
distinguish  between  it  and  the  veins,  but  this  is  not  always  the  case  in  the  living 
subject.  The  veins  may  have  some  pulsation  transmitted  to  them  from  the  adjacent 
arteries  and  the  artery  may  temporarily  ha\e  its  pulsations  stopped  by  pressure  from 
the  retractors.  The  li\'ing  artery  touched  by  the  finger  seems  soft  and  does  not  give 
the  hard,  resisting  impression  felt  in  palpating  the  radial  in  feeling  the  pulse.  The 
difference  in  thickness  of  the  coats  is  also  sometimes  not  apparent  at  a  first  glance. 

The  ligature  is  to  be  passed  from  without  inward  so  as  to  guard  against  wounding 
the  internal  carotid. 

Ligatio7i  of  the  Superior  Thyroid  Artery. — The  superior  thyroid  is  the  first 
branch  of  the  external  carotid  and  is  given  off  close  down  to  the  bifurcation  or  even 
from  the  common  carotid  itself  just  below.  It  lies  quite  superficial  but  of  course 
beneath  the  deep  fascia.  At  first  it  inclines  upward  and  then  makes  a  bend  and  goes 
downward  to  the  thyroid  gland.  It  gives  off  three  comparatively  small  branches, 
the  hyoid  along  the  lower  border  of  the  hyoid  bone,  the  sternomastoid  to  the  muscle 
of  that  name,  and  the  superior  laryngeal  to  the  interior  of  the  larynx.  The  larger 
portion  of  the  artery  goes  downward  to  supply  the  thyroid  gland  and  muscles  over 
it,  therefore  the  artery  is  to  be  looked  for  at  the  upper  edge  of  the  thyroid  cartilage, 
and  not  near  the  hyoid  bone.  The  incision  is  the  same  as  for  ligating  the  external 
carotid  low  down,  viz. ,  5  cm.  along  the  anterior  edge  of  the  sternomastoid  muscle,  its 
middle  being  opposite  the  upper  edge  of  the  thyroid  cartilage.  Veins  from  the  thyroid 
gland — superior  thyroid — will  probably  cover  it.  After  the  deep  fascia  has  been 
opened,  the  external  carotid  is  to  be  recognized  at  its  origin  from  the  common  carotid 
and  then  the  superior  thyroid  artery  found  and  followed  out  from  that  point.  The 
ligature  is  to  be  passed  from  above  downward  to  avoid  the  superior  laryngeal  nerve. 
This  nerve  lies  distinctly  above  the  artery  and  is  not  liable  to  be  injured  if  the  thyroid 
artery  is  followed  out  from  its  origin  at  the  external  carotid.  Treves  suggests  ligat- 
ing it  between  the  sternomastoid  and  superior  laryngeal  branches,  but  it  is  more 
readily  reached  closer  to  the  external  carotid  artery. 

Ligation  of  the  Lingual  Artery. — The  lingual  artery  may  be  ligated  for  wounds, 
as  a  preliminary  step  to  excision  of  the  tongue,  and  to  check  the  growth  of  or  bleed- 
ing from  malignant  growths  of  the  tongue,  mouth,  or  lower  jaw. 

The  lingual  artery  springs  from  the  external  carotid  opposite  the  hyoid  bone 
about  I  cm.  above  the  bifurcation  of  the  common  carotid.  It  is  composed  of  three 
parts:   the  first,   from  its  point  of  origin  to  the  posterior  edge  of  the  hyoglossus 


146 


APPLIED    ANATOMY. 


muscle;  the  second,  the  part  beneath  the  hyoglossus  muscle;  and  the  third,  the  part 
beyond  this  muscle  to  the  tip  of  the  tongue. 

The  artery  is  usually  ligated  beneath  the  hyoglossus  muscle  in  the  second  part  of 
its  course,  although  it  is  sometimes  desirable  to  ligate  it  in  the  first  part  of  its  course. 

The  Jirst  part  inclines  upward  and  forward,  above  the  greater  horn  of  the  hyoid 
bone,  to  the  hyoglossus  muscle,  beneath  which  it  passes  in  a  direction  somewhat 
parallel  to  the  upper  edge  of  the  hyoid  bone.  It  lies  on  the  middle  constrictor  of 
the  pharynx  and  superior  larnygeal  nerve  and  is  covered  by  the  skin,  platysma,  and 
fascia.  It  lies  immediately  below  the  stylohyoid  and  digastric  muscles  and  is  crossed 
by  the  hypoglossal  nerve  and  some  veins.  This  portion  frequently  gives  of?  a  hyoid 
branch  which  runs  above  the  hyoid  bone.  It  is  often  missing,  in  which  case  the 
parts  are  supplied  by  the  hyoid  branch  of  the  superior  thyroid.  From  either  the  end 
of  the  first  part  or  the  beginning  of  the  second  part,  the  dorsalis  linguae  branch  arises. 

The  second  part  of  the  lingual  lies  on  the  superior  constrictor  and  geniohyoglos- 
sus  muscles  and  is  covered  by  the  hyoglossus.  It  runs  in  a  direction  somewhat 
parallel  to  the  upper  edge  of  the  hyoid  bone  and  from  0.5  to  i  cm.  above  it.      In  this 


/ 


Mylohyoid  muscle 

Submaxillary  gland  — 

Anterior  belly  of 
digastric  muscle 


Lingual  artery 

Tendon  of 
digastric  muscle 


Hypoglossal  nerve 
vLingual  vein 
vCut  edge  of  the  hyoglossus  muscle 
Fig.  174. — Ligation  of  the  lingual  artery 

part  of  its  course  it  is  usually  accompanied  by  one  or  two  veins  and  the  hypoglossal 
nerve  is  superficial  to  it,  the  hyoglossus  muscle  separating  them.  This  is  the  part 
of  the  artery  chosen  for  ligation.  An  incision  is  made,  convex  downward,  running 
from  below  and  to  one  side  of  the  symphysis  nearly  down  to  the  hyoid  bone  and 
then  sloping  upward  and  back,  stopping  short  of  the  line  of  the  facial  artery,  which 
can  be  determined  by  the  groove  on  the  mandible  just  in  front  of  the  masseter  muscle. 
The  skin,  superficial  fascia,  and  platysma  having  been  raised,  the  submaxillary  gland 
is  seen  covered  with  a  comparatively  thin  deep  fascia.  Some  veins  coming  from  the 
submental  region  may  then  be  encountered.  They  may  be  ligated  and  divided. 
The  submaxillary  gland  is  next  to  be  lifted  from  its  bed  and  turned  upward  against 
the  mandible,  carrying  with  it  the  facial  artery,  which  is  adherent  to  its  under  sur- 
face. The  tendon  of  the  digastric  will  now  be  seen  with  the  anterior  and  posterior 
belHes  of  the  muscle  forming  an  angle  with  its  point  toward  the  hyoid  bone.  These 
with  the  hypoglossal  nerve  form  what  has  been  called  the  triangle  of  Lesser.  It  is 
in  this  space  that  the  artery  is  ligated.  The  floor  of  the  space  posteriorly  is  formed 
by  the  hyoglossus  muscle,  while  anteriorly  is  seen  the  edge  of  the  mylohyoid  muscle. 
Through  the  thin  fascia  overlying  the  hyoglossus  muscle  can  be  seen  the  hypoglossal 


THE   NECK.  147 

nerve,  and  below  it,  sometimes  a  vein.     The  artery  lies  under  the  muscle,  while  the 
veins  may  be  either  on  or  under  the  muscle  or  both. 

The  apex  of  the  angle  formed  by  the  tendon  of  the  digastric  muscle  is  held 
down  to  the  hyoid  bone  by  a  slip  of  fascia  which  is  an  expansion  of  the  central 
tendon  of  the  muscle  and  the  tendon  of  the  stylohyoid  muscle.  The  distance  at 
which  the  central  tendon  of  the  digastric  is  held  away  from  the  hyoid  bone  varies 
in  different  individuals  and  is  an  important  fact  to  bear  in  mind  in  searching  for 
the  artery.  If  the  tendon  rests  high  above  the  hyoid  bone  the  artery  must  be 
looked  for  low  down,  sometimes  even  under  the  tendon;  if,  on  the  contrary,  the 
tendon  is  low  down  the  artery  may  be  o.  5  to  i  cm.  higher  up.  The  hypoglossal  nerve 
lies  on  the  muscle  and  nearer  to  the  mandible  than  the  artery.  If  there  is  a  vein  on 
the  hyoglossus  muscle  it  is  apt  to  be  below  the  nerve,  that  is,  nearer  the  hyoid  bone, 
and  may  lie  directly  o\er  the  artery.  The  vein  and  the  nerve  are  to  be  displaced 
up  towards  the  jaw  and  an  incision  a  centimetre  long  made  through  the  hyoglossus 
muscle  a  short  distance  above  the  digastric  tendon  and  parallel  with  the  hyoid  bone. 
This  incision  should  not  be  deep,  as  the  muscle  is  only  2  or  3  mm.  (^  in.)  thick. 


Middle  scalene  muscle 

Posterior  scalene  muscle 


Stemomastoid  muscle,  ^        ^         ^      t        ,    \ 

^^      y^       /  \    \  \  ^"-Omohyoid  muscle 

Phrenic  nerve 

Anterior  scalene  muscle . 

Subclavian  vein  I  l  \  Suprascapular  artery  and  vein 

Cords  of  brachial  plexus         /  Transverse  cervical  artery  and  vein 

Subclavian  artery 

Fig.  175. — Ligation  of  the  subclavian  artery 

The  edges  of  the  incision  being  raised  and  displaced  upward  and  downward,  the  artery 
will  probably  be  seen  running  at  right  angles  to  the  fibres  of  the  muscle  and  parallel  to 
the  hyoid  bone.  If  not  seen  at  once  it  should  be  looked  for  below  the  incision, 
nearer  to  the  hyoid  bone.  Care  must  be  taken  not  to  mistake  the  vein  for  the  artery. 
That  this  is  not  an  unlikely  thing  is  shown  by  its  occurring  in  the  hands  of  a  distin- 
guished surgeon  who  had  had  exceptional  experience  in  this  same  operation.  The 
ligature  needle  may  be  passed  from  above  downward  to  avoid  including  the  hypo- 
glossal nerve. 

Subclavian  Artery. — The  right  subclavian  artery  runs  from  the  sternoclavicular 
articulation  in  a  curved  line  to  the  middle  of  the  clavicle.  It  rises  1.25  cm,  (^  in,, 
Walsham)  above  the  clavicle.  The  innominate  bifurcates  opposite  the  right  sterno- 
clavicular joint.  The  left  subclavian  springs  direcdy  from  the  arch  of  the  aorta, 
therefore  it  is  longer  than  the  right  by  4  to  5  cm.,  this  being  the  length  of  the  in- 
nominate. As  the  subclavian  artery  passes  outward  it  is  crossed  by  the  scalenus 
anticus  muscle,  which  divides  it  into  three  parts  :  the  first  part,  extending  to  the 
inner  side  of  the  muscle,  gives  off  three  branches,  the  vertebral,  internal  majnmary , 
and  thyroid  axis;  the  second  part,  behind  the  muscle,  gives  off  the  superior  intercos- 
tal; the  third  part  has  no  branches. 


148  APPLIED    ANATOMY. 

1^\\Q  first  portion  of  the  siibclavian  lies  very  deep  and  operations  on  it  have  been 
so  unsuccessful  that  they  have  been  practically  abandoned.  As  it  is  frequently 
involved  in  aneurisms  its  relations  are  worth  studying.  In  approaching  the  artery 
from  the  surface  it  is  seen  to  be  covered  by  the  sternomastoid,  the  sternohyoid, 
and  the  sternothyroid  muscles.  The  outer  edge  of  the  sternomastoid  muscle  corre- 
sponds with  the  outer  edge  of  the  scalenus  anticus.  The  three  first-named  muscles 
having  been  raised,  the  artery  is  seen  to  be  crossed  by  the  internal  jugular,  the 
vertebral,  and  perhaps  the  anterior  jugular  veins.  The  anterior  jugular  above  the 
clavicle  dips  beneath  the  inner  edge  of  the  sternomastoid  muscle  to  pass  outward 
and  empty  into  the  external  jugular  or  subclavian.  The  pneumogastric  nerve  crosses 
the  artery  just  to  the  inner  side  of  the  internal  jugular  vein.  Below,  the  artery  rests 
on  the  pleura,  and  on  the  right  side  the  recurrent  laryngeal  nerve  winds  around  it. 
Behind  the  artery  are  the  pleura  and  lung,  which  rise  somewhat  higher  in  the  neck 
than  does  the  artery. 

On  the  left  side  the  phrenic  nerve  leaves  the  scalenus  anticus  muscle  at  the  first 
rib,  crosses  the  subclavian  at  its  inner  edge,  and  passes  down  on  the  pleura  to  cross 
the  arch  of  the  aorta.  To  the  inner  side  of  the  artery  runs  the  thoracic  duct,  which, 
as  it  reaches  the  upper  portion  of  the  artery,  curves  over  it  to  cross  the  scalenus 
anticus  muscle  and  empty  into  the  junction  of  the  internal  jugular  and  subclavian 
veins.  The  trachea  and  oesophagus  are  likewise  seen  to  the  inner  side  of  the  artery. 
The  thyroid  axis  comes  of?  its  anterior  surface,  the  vertebral  from  its  posterior,  and 
the  internal  mammary  below. 

The  second  portion  of  the  subclavian  artery  lies  behind  the  anterior  scalene 
muscle.  In  front  of  the  anterior  scalene  is  the  subclavian  vein.  The  phrenic  nerve 
runs  on  the  muscle  and  at  the  first  rib  leaves  it  to  continue  down  between  the  right 
innominate  vein  and  pleura.  Behind  and  below,  the  artery  rests  on  the  pleura  and 
the  middle  scalene  muscle  is  to  its  outer  side.  Thus  it  is  seen  that  the  artery  passes 
through  a  chink  formed  by  the  anterior  scalene  muscle  in  front  and  the  middle 
scalene  behind.  They  both  insert  into  the  first  rib.  The  posterior  scalene  is  farther 
back  and  inserts  into  the  second  rib.  Above  the  artery  are  all  the  cords  of  the 
brachial  plexus.  One  branch  of  the  subclavian,  the  superior  intercostal  artery,  is 
given  off  near  the  inner  edge  of  the  anterior  scalene  muscle. 

The  third portio7i  of  the  subclavian  runs  from  the  outer  edge  of  the  anterior  scalene 
muscle  to  the  lower  border  of  the  first  rib.  This  part  of  the  artery  is  the  most  super- 
ficial. The  only  muscle  covering  it  above  is  the  thin  sheet  of  the  platysma,  lower 
down  the  subclavius  muscle  and  clavicle  overlie  it;  but  the  operations  on  the  vessel 
are  done  above  these  structures,  hence  they  do  not  interfere.  There  are  apt  to  be  a 
number  of  veins  in  front  of  the  artery.  The  external  jugular  and  transverse  cervical 
veins  are  certain  to  be  present  and  perhaps  the  suprascapular  and  cephalic,  which 
may  enter  above  instead  of  below  the  clavicle.  These  veins  may  form  a  regular  net- 
work in  the  posterior  cervical  triangle  above  the  clavicle  and  prove  very  troublesome. 
Above  is  the  brachial  plexus  and  transverse  cervical  artery  and  still  higher  is  seen  the 
omohyoid  muscle.  The  suprascapular  artery  is  lower  down  and  usually  concealed 
just  below  the  upper  edge  of  the  clavicle.  The  lowest  cord  of  the  brachial  plexus, 
formed  by  the  first  dorsal  and  last  cervical  nerves,  may  be  posterior  to  the  artery. 
The  nerve  to  the  subclavius  muscle  passes  down  in  front  of  it. 

Ligation  of  the  Third  Portion  of  the  Subclavian  Artery. — The  head  is  to  be 
turned  strongly  to  the  opposite  side  and  the  shoulder  depressed.  This  lowers  the 
clavicle  and  raises  the  omohyoid  muscle  and  therefore  gives  more  room  to  work. 
The  skin  is  to  be  drawn  down  and  an  incision  7.5  cm.  long  made  on  the  clavicle. 
The  drawing  down  of  the  skin  is  done  to  avoid  wounding  the  external  jugular  vein. 
This  vein  is  really  fastened  to  the  deep  fascia,  and  the  skin,  platysma,  and  super- 
ficial fascia  slide  over  it.  On  releasing  the  skin  it  slides  up  above  the  clavicle.  The 
middle  of  the  incision  should  be  a  little  to  the  inside  of  the  middle  of  the  clavicle. 
The  deep  fascia  is  to  be  incised  and  the  clavicular  origin  of  the  sternomastoid 
and  trapezius  muscles  cut  to  the  same  extent  as  the  superficial  incision.  The  length 
of  the  adult  male  clavicle  is  about  15  cm   (6  in.). 

The  clavicular  origin  of  the  sternomastoid  extends  out  on  the  clavicle  one-third 
of  its  length.     The  trapezius  inserts  into  the  outer  third.     This  leaves  the  middle 


THE   NECK.  149 

third  or  5  cm.  of  the  cla\'icle  on  its  upper  surface  JFree  from  muscles.  As  the 
incision  is  7.5  cm.  long  this  necessitates  the  division  of  2.5  cm.  (i  in.)  of  muscle, 
and  as  the  middle  of  the  incision  is  a  little  to  the  inner  side  of  the  middle  of  the 
clavicle  this  will  make  it  necessary  to  divide  more  of  the  clavicular  origin  of  the 
sternomastoid  than  of  the  trapezius.  After  the  division  of  the  deep  fascia,  fat  and 
veins  are  encountered.  The  scalenus  anticus  muscle  has  the  subclavian  vein  in 
front  of  it  and  the  artery  behind,  therefore  the  vein  must  be  attended  to  before  a 
search  is  made  for  the  edge  of  the  scalene  muscle.  The  veins  to  be  encountered  are 
the  external  jugular  vein,  which  empties  into  the  subclavian  in  front  of  or  to  the 
outer  side  of  the  anterior  scalene  muscle,  and  its  tributaries,  the  suprascapular  and 
transverse  cervical  veins,  as  well  as  the  anterior  jugular  and  a  communicating  branch 
from  the  opposite  side  of  the  neck.  The  cephalic  vein  not  infrequently  sends  a 
communicating  branch  over  the  clavicle  to  empty  into  the  external  jugular.  The 
fat  is  to  be  picked  away  with  forceps;  the  veins  are  to  be  held  out  of  the  way  with  a 
blunt  hook  or  ligated  and  cut.  The  suprascapular  artery  may  be  seen  close  to  or 
under  the  cla\icle.  The  transverse  cervical  artery  may  perhaps  be  above  the  level 
of  the  wound.  The  omohyoid  muscle  may  or  may  not  be  seen,  as  its  distance  from 
the  clavicle  is  quite  variable.  The  transverse  cervical  and  suprascapular  arteries 
are  not  to  be  cut,  as  they  are  needed  for  the  collateral  circulation.  As  was 
mentioned  in  speaking  of  the  ligation  of  the  external  carotid  artery,  so  also  here  it 
is  not  always  easy  to  distinguish  between  arteries  and  veins.  The  veins  being 
disposed  of,  the  anterior  scalene  muscle  is  to  be  sought  at  the  internal  portion  of  the 
wound.  It  runs  somewhat  like  the  lower  portion  of  the  sternomastoid,  the  posterior 
edges  of  the  two  muscles  coinciding.  The  phrenic  nerve  runs  down  first  on  the 
anterior  surface  and  then  on  the  inner  surface  of  the  scalenus  anticus.  The  edge  of 
the  muscle  being  recognized,  by  following  it  down  the  finger  feels  the  first  rib.  The 
artery  lies  on  the  first  rib  immediately  behind  the  muscle  and  the  vein  immediately  in 
front  of  the  muscle.  The  tubercle  on  the  first  rib  may  not  be  readily  felt  because  the 
muscle  is  inserted  into  it.  The  prevertebral  fascia  coming  down  the  scalenus  anticus 
muscle  passes  from  it  to  the  subclavian  artery,  forming  its  sheath;  hence,  as  pointed 
out  by  George  A.  Wright,  of  Manchester  {^Annals  of  Surgery,  1888,  p.  362),  the 
edge  of  the  muscle  may  not  readily  be  distinguished  and  the  brachial  plexus  is  a 
better  guide.  This  is  above  the  artery  and  the  lower  cord  of  the  plexus  lies  directly 
alongside  of  the  artery.  It  is  closer  to  the  artery  above  and  to  its  outer  side  than 
the  subclavian  vein  is  below  and  to  its  inner  side.  The  greatest  care  should  be 
exercised  in  passing  the  aneurism  needle  around  the  artery.  The  vein  is  not  so 
much  in  jeopardy  as  are  the  pleura  and  lowest  cord  of  the  brachial  plexus,  hence  the 
needle  is  passed  from  above  down  between  the  ner\-e  and  the  artery  and  brought 
out  between  the  artery  and  vein. 

Wounding  of  the  pleura  may  cause  collapse  of  the  lung  and  later  a  septic 
pleurisy,  while  including  the  nerve  will  cause  severe  pain,  etc. 

Collateral  CircidaUon  after  Ligation  of  the  Third  Portion  of  the  Subclavian  Artery. 
— (1)  Internal  mammary  with  superior  thoracic  and  long  thoracic.  (2)  The  poste- 
rior scapular  branch  of  the  suprascapular  with  the  dorsalis  branch  of  the  subscap- 
ular. (3)  Acromial  branches  of  suprascapular  with  acromial  branch  of  acromial 
thoracic.  (4)  A  number  of  small  vessels  derived  from  branches  of  the  subclavian 
above  with  axillary  branches  of  the  main  axillary  trunk  below  (Gray). 

Ligation  of  the  Inferior  Thyt'oid  Artery. — The  inferior  thyroid  artery,  unlike 
the  superior,  lies  deep  from  the  surface,  and  it  is  a  far  more  difificult  vessel  to  reach.  It 
is  a  branch  of  the  thyroid  axis,  the  other  branches  being  the  transverse  cervical  and 
suprascapular.  The  thyroid  axis  comes  from  the  first  part  of  the  subclavian  just  a 
little  to  the  inner  side  of  the  edge  of  the  scalenus  anticus  muscle.  The  inferior 
thyroid  artery  ascends  on  the  longus  colli  muscle,  just  to  the  inner  side  of  the 
scalenus  anticus  and  almost  in  front  of  the  vertebral  artery.  When  it  reaches  about 
the  level  of  the  sexenth  cervical  vertebra  it  bends  inward  and  behind  the  carotid 
artery  to  reach  the  lower  posterior  edge  of  the  thyroid  gland.  The  transverse 
process  of  the  sixth  cervical  vertebra,  called  the  caj'otid  tubercle  of  Chassaignac,  is 
above  it.  As  it  bends  to  go  inward  it  gives  off  the  ascending  cervical  artery.  In 
front  of  the  artery  are  the  internal  jugular  vein,  common  carotid  artery,  pneumo- 


15° 


APPLIED    ANATOMY. 


gastric  nerve,  and  the  middle  ganglion  of  the  sympathetic.  The  recurrent  laryngeal 
nerve  usually  passes  upward  behind  the  branches  of  the  artery  just  before  they  enter 
the  thyroid  gland.  The  thoracic  duct  on  the  left  side  passes  over  the  front  of  the 
artery  low  down. 

Operation. — An  incision  7.5  cm.  long  is  made  along  the  anterior  border  of  the 
sternomastoid  muscle,  extending  upward  from  the  clavicle.  This  will  bring  the  upper 
extremity  up  to,  or  even  above,  the  cricoid  cartilage.  The  anterior  jugular  vein 
will  have  to  be  ligated  and  the  muscle  displaced  outward.  The  common  carotid 
artery  should  then  be  isolated  and  it,  together  with  the  pneumogastric  nerve  and 
internal  jugular  vein,  drawn  outward.  The  omohyoid  muscle  may  appear  at  the 
upper  edge  of  the  incision.  Feel  for  the  carotid  tubercle  on  the  sixth  transverse 
cervical  process:  the  artery  lies  below  the  omohyoid  muscle  and  cricoid  cartilage  and 
below  the  tubercle  and  beneath  the  sheath  of  the  carotid.  If  the  trunk  of  the  sym- 
pathetic or  its  middle  cervical  ganglion,  which  lies  on  the  artery,  is  encountered,  it 


Profunda  cervicis 
Transverse  cervical 


Posterior  scapular 


Acromial  thoracic 


Subscapular 
Dorsalis  scapulae 

Long  thoracic 


Inferior  thyroid 
Common  carotid 
Vertebral 
Innominate 


Superior  intercostal 
—  Subclavian 
/  ~    -Superior  thoracic 
— -  Internal  mammary 


Fig.  176. — Collateral  circulation  after  ligation  of  the  third  portion  of  the  subclavian  artery. 

should  be  pushed  to  the  inner  side,  the  artery  isolated  outwardly  and  ligature  applied. 
Do  not  go  too  far  out  or  the  scalenus  anticus  will  be  reached  and  the  phrenic  nerve 
may  be  injured,  nor  too  far  in,  to  avoid  wounding  the  recurrent  laryngeal. 

The  thyroidea  hna  {inferior  thyroid^  vei^is  do  not  cross  outward  nor  accompany 
the  artery,  but  proceed  downward  on  the  trachea  to  empty  into  the  innominate  veins. 


THE  CERVICAL  FASCIAS. 

There  are  two  fascias  in  the  neck,  the  superficial  and  the  deep.  The  super- 
ficial fascia  has  blended  with  it  anteriorly  the  platysma  muscle  and  the  termination  of 
the  nerves,  arteries,  and  veins.  The  main  trunks  of  these  structures  lie  for  all 
practical  purposes  beneath  the  superficial  fascia  and  adherent  to  the  surface  of  the 
deep  fascia.  It  is  for  this  reason  that  in  raising  the  superficial  structures  the  larger 
trunks  remain  applied  to  the  deep  fascia  and  are  thus  less  liable  to  be  injured  in  the 
living  and  mutilated  in  the  dead.  In  the  superficial  fascia  and  on  the  deep  fascia  are 
the  superficial  lymphatics. 


THE    NECK. 


151 


The  superticial  lymphatic  nodes  frequently  suppurate.  When  they  do  the 
abscess  so  formed  is  prevented  by  the  deep  fascia  from  reaching  the  parts  beneath,  so 
the  pus  works  its  way  out  through  the  skin.  As  the  superficial  fascia  is  loose,  if 
the. abscess  is  slow  in  formation,  it  may  extend  for  a  considerable  distance  under  the 
skin. 

Sebaceous  cysts  are  common  in  the  neck.  As  they  are  superficial  to  the  deep 
fascia,  which  is  not  involved,  they  can  be  removed  without  fear  of  wounding  any 
important  structures.  The  veins  do  not  overlie  them;  they  are  always  superficial 
to  the  veins,  therefore  there  is  no  danger  of  wounding  the  external  jugular. 

The  Deep  Cervical  Fascia. — The  deep  cervical  fascia  completely  envelops 
the  neck  and  sends  its  branches  in  between  all  its  various  structures.  It  is  the 
fibrous  tissue  that  both  unites  and  separates  all  the  different  structures  to  and  from 
each  other.  Where  this  fascia  is  abundant  it  forms  a  distinct  layer,  but  where  it  is 
scant  it  is  simply  a  small  amount  of  connective  tissue  between  two  adjacent  parts. 


Anterior  jugular  veins 


Larynx^ 
Superficial  layer  of  deep  cervical  fascia, 
Pretracheal  layer 
Cricoid  cartilage 

Cricothyroid  muscle 
Prevertebral  layer 
LoDgus  colli 


Sternohyoid  muscle 
Sternothyroid 
Thyroid  gland 
/     Omohyoid 


Carotid  artery 
Sternomastoid 


Trachelomastoid 


Sixth  vertebra 


Longus  colli 

Internal  jugular  vein 
Trachelomastoid 


Scale 


>  anticus  and  medius 


External  jugular  vein 
Scalenus  posticus 

Levator  scapuLc 
Splenius  colli 
Splenius  capitis 


Trapezius 

Com  plexus 
Multifidus  spinoe 
Semispinales  cervices 
Fig.  177. — Transverse  section  of  the  neck  through  the  sixth  cervical  vertebra. 

To  follow  all  the  processes  of  the  deep  fascia  through  the  neck  between  its  innumer- 
able structures  is  impossible — nor  is  it  necessary.  The  main  reason  for  studying  the 
deep  cervical  fascia  and  its  various  parts  is  to  understand  the  course  pursued  by 
abscesses  and  infections.  This  is  best  done  by  limiting  oneself  to  the  main  super- 
ficial layer  and  some  of  the  larger  layers  crossing  from  side  to  side. 

The  principal  layers  of  the  deep  cervical  fascia  are  the  stiperjicial  layer,  which 
completely  encircles  and  envelops  the  neck,  the  prevertebral  layer,  which  passes 
from  side  to  side  in  front  of  the  spinal  column,  and  the  pretracheal  layer,  which  passes 
from  side  to  side  in  front  of  the  trachea. 

The  Superficial  Layer. — The  superficial  layer  of  the  deep  fascia  envelops  the 
whole  of  the  neck,  with  the  exception  of  the  skin,  platysma,  and  superficial  fascia. 
It  is  attached  above  to  the  occipital  protuberance,  the  superior  curved  line  of  the  occi- 
put, the  mastoid  process,  then  blends  with  the  capsule  of  the  parotid  gland,  then  passes 
to  the  angle  of  the  jaw  and  along  the  body  of  the  mandible  to  the  symphysis, 
whence  it  proceeds  around  the  opposite  side  in  the  same  manner.  Below  it  is 
attached  to  the  sternum,  upper  edge  of  the  clavicle,  acromion  process  and  spine  of 
the  scapula,  thence  across  to  the  vertebral  spines,  to  which  and  to  the  ligamentum 


APPLIED    ANATOMY. 

nuchae  it  is  attached  up  to  the  occipital  protuberance.  In  the  front"oF  the  neck  it 
passes  from  the  mandible  down  to  be  attached  to  the  hyoid  bone  and  thence  down- 
ward to  the  sternum  and  clavicle. 

From  the  under  side  of  this  superficial  layer  processes  of  fascia  come  oE  and 
envelop  the  various  structures  of  the  neck.  Every  separate  structure  of  the  neck 
is  covered  by  it  and  therefore  separated  from  the  adjacent  parts  by  a  more  or  less  dis- 
tinct layer  of  the  fascia.  In  many  places  it  is  quite  thin  or  almost  imperceptible, 
amounting  to  but  a  few  shreds  of  fibrous  tissue,  in  other  places  it  is  more  distinct, 
forming  more  or  less  marked  capsules,  as  in  the  case  of  the  thyroid  and  submaxillary 
glands,  or  fibrous  layers,  as  in  the  case  of  those  in  front  of  the  vertebrae  and  trachea. 
Posteriorly  in  the  median  line  the  superficial  layer  of  the  deep  fascia  sends  a  process 
which  covers  the  under  surface  of  the  trapezius  muscle.  Anteriorly  another  process 
is  given  ofl  to  cover  the  under  surface  of  the  sternomastoid  muscle.     The  super- 


Prevertebral  fascia 
Pneumogastric  nerve 
Common  carotid  artery 
Internal  jugular  vein 
Sheath  of  the  vessels 

Superficial  layer  of  deep  fascia 

CEsophagus 

Trachea 

Thyroid  gland 

Pretracheal  fascia 


4 


Fig   178. — Deep  cervical  fascia. 


The  pharynx  and  larynx  have  been  cut  away,  exposing  the  prevertebral  and 
pretracheal  layers. 


ficial  veins  of  the  neck,  the  anterior,  external,  and  posterior  jugulars,  lie  on  or  in 
the  deep  fascia,  being  stuck  to  or  blended  with  its  upper  surface. 

About  3  cm.  ( I  ^  in. )  above  the  sternum  the  deep  fascia  splits  into  two  layers, 
one  to  be  attached  to  the  anterior  and  the  other  to  the  posterior  edge  of  the  sternum 
in  front  of  the  sternohyoid  and  sternothyroid  muscles.  Between  these  two  layers  is 
the  space  of  Bums ;  it  contains  the  lower  ends  of  the  anterior  jugular  veins  with 
the  branch  that  joins  them,  some  fatty  tissue  and  lymphatic  nodes,  and  the  sternal 
origin  of  the  sternomastoid  muscle.  Sometimes  a  vein  comes  up  from  the  surface  of 
the  chest  below  to  open  into  the  anterior  jugular  vein. 

The  prevertebral  layer  passes  from  side  to  side  directly  on  the  bodies  of  the 
vertebrae.  It  covers  the  muscles  attached  to  the  spine,  as  the  scalene,  longus  colli, 
rectus  capitis  anticus,  and  also  the  nerves,  as  those  of  the  brachial  plexus,  coming 
from  the  spine.  On  reaching  the  carotid  artery  and  jugular  vein  it  helps  to  form 
their  sheath.  Its  upper  edge  is  attached  to  the  base  of  the  skull  at  the  jugular  fora- 
men and  carotid  canal  and  thence  across  the  basilar  process  to  the  opposite  side. 
Inferiorly  it  passes  down  on  the  surface  of  the  bodies  of  the  vertebrae  into  the  pos- 
terior mediastinum. 


THE    NECK.  153 

From  the  sheath  of  the  vessels  outward,  beyond  the  posterior  edge  of  the  sterno- 
mastoid  muscle,  the  prevertebral  fascia  covers  the  scalene  muscles,  the  brachial  plexus 
of  nerves,  and  the  subclavian  artery.  On  reaching  the  clavicle  the  fascia  is  attached 
to  its  upper  surface,  blending  with  the  superficial  layer;  it  is  then  continued  down 
over  the  subclavian  muscle,  forming  its  sheath,  and  ends  as  the  costocoracoid  mem- 
brane. The  part  over  the  subclavian  artery  and  vein  is  continued  over  them  and 
the  brachial  plexus  and  follows  them  into  the  axilla.  This  fascia  forms  the  floor  of 
the  posterior  cervical  triangle;  the  roof  is  formed  by  the  superficial  layer  of  the  deep 
fascia.  It  is  between  these  layers  that  the  suprascapular  artery  and  veins  nm.  The 
descending  branches  of  the  cervical  plexus,  the  spinal  accessory  nerve,  omohyoid 
muscle,  and  some  fat  and  lymph-nodes  are  also  found  there. 

The  pretracheal  layer  passes  from  side  to  side  in  front  of  the  trachea.  Laterally 
it  too  blends  with  the  sheath  of  the  vessels  and  is  continued  posteriorly  behind  the 
pharynx  and  oesophagus  as  the  buccopharyngeal  fascia.  In  front  it  blends  in  the 
median  line  with  the  superficial  layer  and  is  attached  to  the  hyoid  bone  and  cricoid 
cartilage.  It  splits  to  enclose  and  form  a  capsule  for  the  thyroid  gland,  and  below  en- 
closes in  its  meshes  the  inferior  thyroid  veins,  and  thence  passes  to  the  arch  of  the 
aorta  to  be  continuous  with  the  pericardium.  Laterally  it  passes  under  the  sterno- 
hyoid, omohyoid,  and  sternothyroid  muscles  to  blend  with  the  sheath  of  the  vessels 
and  the  layer  on  the  posterior  surface  of  the  sternomastoid  muscle.  This  is  its 
lateral  limit.  Underneath  the  sternomastoid  muscle  a  loop  of  fascia  proceeds  down- 
ward from  the  omohyoid  muscle  to  the  first  rib.  This  is  derived  from  the  sheath 
of  the  vessels  beneath  and  the  layer  on  the  under  surface  of  the  sternomastoid 
superficially. 

The  sheath  of  the  vessels  envelops  the  carotid  artery,  jugular  vein,  and  pneumo- 
gastric  nerve.  Thin  layers  of  fascia  pass  between  these  structures,  separating  one 
from  the  other.  The  sheath  is  formed  by  the  union  of  the  outer  edge  of  the  pre- 
tracheal fascia  and  the  prevertebral  fascia,  with  the  fascia  lining  the  under  surface  of 
the  sternomastoid  muscle.  This  sheath  follows  the  vessels  down  into  the  chest  and 
out  into  the  axilla. 

The  capsule  of  the  parotid  gla^id  is  formed  by  the  splitting  of  the  superficial 
layer  of  the  deep  cer\ical  fascia  as  it  passes  from  the  mastoid  process  to  the  angle  of 
the  jaw.  Its  superficial  portion  is  attached  to  the  zygomatic  process.  Its  deep  por- 
tion passes  from  the  styloid  process  to  the  angle  of  the  jaw  and  is  known  as  the 
stylomandibular  ligament. 

The  capsule  of  the  submaxillary  gland  \s  formed  by  a  splitting  of  the  superficial 
layer  at  the  hyoid  bone.  It  forms  the  covering  of  the  gland  and  from  the  hyoid 
bone  sends  a  process  upward  which  lies  on  the  digastric  and  mylohyoid  muscles 
and  follows  the  latter  up  to  be  attached  along  the  mylohyoid  ridge  of  the  mandible. 
It  proceeds  with  the  submaxillary  gland  around  the  posterior  edge  of  the  mylohyoid 
muscle  to  cover  its  upper  surface.  The  stylomandibular  ligament  alluded  to  above 
separates  the  parotid  from  the  submaxillary  gland. 

The  capsule  of  the  thyroid  gland  is  not  very  thick  and  the  gland  is  readily 
separated  from  it,  as  is  also  the  case  w  ith  the  submaxillary  gland.  It  is  continued 
downward  in  front  of  the  trachea  as  the  pretracheal  layer  and  laterally  it  blends  with 
the  sheath  of  the  vessels.  It  follows  the  vessels  downward  into  the  chest  and  is 
continuous  with  the  pericardium.  The  veins  of  the  gland,  which  are  at  times  very 
large,  run  beneath  the  capsule  and  bleed  freely  if  wounded. 

The  Buccopharyngeal  Fascia. —  Between  the  pharynx  in  front  and  the  ver- 
tebral column  behind  is  the  retropharyngeal  space.  The  fascia  forming  the  pos- 
terior wall  of  this  space  is  the  prevertebral  fascia  already  described.  Forming  its 
anterior  wall  is  a  thin  layer  of  connective  tissue  called  the  buccopharyngeal  fascia. 
It  invests  the  superior  constrictor  of  the  pharynx  and  is  continued  forward  on  the 
buccinator  muscle.  It  is  continued  downward  behind  the  pharynx  and  oesophagus 
into  the  posterior  mediastinum:  laterally  it  blends  with  the  sheath  of  the  vessels 
and  is  continuous  with  the  pretracheal  fascia  around  the  larynx,  trachea,  and  thyroid 
gland  (Fig.   179). 

Abscesses  of  the  Neck. — Abscesses  of  the  neck  usually  arise  in  connection 
with   the  Ivmphatic   nodes.     They  may  also  start  from    infected  wounds,    carious 


■54 


APPLIED   ANATOMY. 


teeth,   suppuration  of  the  thyroid  g-land,  and  other  causes.      They  may  have  then^ 
course  influenced  by  the  various  layers  of  the  deep  fascia. 

Pus  in  the  Submaxillary  RegioJi. — As  the  submaxillary  space  has  the  mylo- 
hyoid muscle  as  its  floor,  abscesses  here  show  below  the  body  of  the  mandible 
between  it  and  the  hyoid  bone.  Usually  they  point  towards  the  skin.  Infection  of 
this  space  may  occur  from  the  teeth.  Tillmans  ("Surgery,"  vol.  i,  p.  434)  saw  a 
case  in  which  in  four  days  the  pus  caused  death  from  infection  of  the  mediastinum 
and  pleura.  This  proceeded  downward  from  a  badly  extracted  tooth  and  thence 
under  the  deep  fascia  of  the  neck  to  the  chest. 

The  pus,  filling  the  submaxillary  space,  as  can  also  occur  in  Ludwig's  angina, 
which  is  an  infective  inflammation  of  the  submaxillary  and  sublingual  regions,  may 
follow  the  lingual  and  facial  arteries  to  the  sheath  of  the  great  vessels  and  down  into 
the  superior  mediastinum.  The  infection  in  Ludwig's  angina  may  pass  around 
the  posterior  edge  of  the  mylohyoid  muscle  and  involve  the  structures  around  the 


Buccinator 


Masseter 


Internal  pterygoid 


Buccopharyngeal 
fascia 

Retropharyngeal 
space 

Prevertebral  fascia 


Posterior  pilla* 
of  fauces 

External  carotid  artery 
Parotid  gland 


Internal  jugular  vein 


Rectus  capitis 


Longus  colli 


Vagus  nerve 
Internal  carotid  artery 


Fig,  179 — Section  through  the  upper  portion  of  the  third  cervical  vertebra,  showing  the  buccopharyngeal  and 
prevertebral  fascias  and  retropharyngeal  space. 

base  of  the  tongue  and  pharynx,  and  produce  oedema  of  the  larynx  and  death  (see 
page  200). 

Pus  superficial  to  the  deep  fascia  tends  to  perforate  the  skin  and  discharge 
externally.  If  it  is  slow  in  forming  it  may  sink  down  and  pass  over  the  clavicle 
onto  the  upper  portion  of  the  chest. 

Pus  in  the  suprasternal  notch  or  space  of  Burns  bulges  anteriorly  but  may 
perforate  posteriorly.  The  sternothyroid  and  sternohyoid  muscles  are  attached  to  the 
posterior  surface  of  the  sternum ;  but  the  layer  of  fascia  on  their  anterior  surface  is 
very  thin,  so  that  pus  may  either  pass  between  the  muscles  or  perforate  them  and  so 
pass  down  in  front  of  the  pretracheal  fascia  close  to  the  under  surface  of  the  sternum. 
It  would  then  tend  to  show  itself  in  the  upper  intercostal  spaces,  close  to  the 
sternum. 

Pus  between  the  pretracheal  and  S7iperficial  layers,  as  may  occur  from  abscesses 
of  the  thyroid  gland,  tends  to  work  its  way  downward  rather  than  laterally.  The 
pretracheal  fascia  at  the  sides  blends  with  the  sheath  of  the  vessels  and  the  fascia 
covering  the  posterior  surface  of  the  sternomastoid  muscles.  In  this  space  lie  the 
sternohyoid,  sternothyroid,  and  omohyoid  muscles.  The  pretracheal  fascia  is  beneath 
them  and  the  superficial  layer  of  the  deep  fascia  above.      Pus  can  follow  the  posterior 


THE    NECK. 


155 


surface  of  these  muscles  down  behind  the  sternum  in  front  of  the  innominate  veins 
and  arch  of  the  aorta. 

Pus  between  the  pretracheal  and  prevertebral  layers  cannot  go  further  to  one 
side  than  the  sheath  of  the  \'essels.  Therefore  it  follows  the  trachea  and  oesophagus 
down  into  the  posterior  mediastinum.  This  space,  between  these  layers,  is  some- 
times called  the  visceral  space  because  it  contains  the  oesophagus,  trachea,  and 
thyroid  gland.  Pus  in  this  space  can  also  perforate  into  the  trachea,  pharynx, 
oesophagus,  or  even  extend  laterally  and  involve  the  great  vessels. 

If  the  anterior  portion  of  the  thyroid  gland  suppurates,  the  pus  may  perforate  the 


Prevertebral  layer 
Cricoid  cartilage 


Hyoid  bone 


Thryoid  cartilage 

Superior  layer  of  deep 
cervical  fascia 


Pretracheal  layer 
Cricoid  cartilage 

Thyroid  gland 
Space  of  Bums 

Left  innominate  vein 

Aorta 

Pericardium 


Fig.  i8o. — The  superficial  layer,  pretracheal  layer,  and  prevertebral  layer  of  the  deep  cervical  fascia. 


thin  pretracheal  fascia  covering  it  and  pass  down  behind  the  sternohyoid  and  sterno- 
thyroid muscles  into  the  anterior  part  of  the  superior  mediastinum. 

Pus  posterior  to  the  prevertebral  fascia,  as  from  caries  of  the  vertebrae,  if  high 
up  may  bulge  into  the  pharynx,  forming  a  retropharyngeal  abscess.  It  may  follow 
the  scaleni  muscles  and  brachial  plexus  down  around  the  axillary  artery  into  the 
axilla.  In  the  neck  it  shows  itself  posterior  to  the  carotid  arteries  and  to  the  older 
edge  of  the  sternomastoid  muscles. 

Pus  i7i  the  sheath  of  the  great  vessels,  when  originating  from  lymphatic  nodes, 
may  first  raise  the  sternomastoid  muscle  and  show  itself  along  its  anterior  border; 
it  may  perforate  the  lumen  of  the  vessels;  it  may  pass  down  with  the  vessels  into  the 
superior  mediastinum;  or  it  may  bulge  into  the  visceral  space  between  the  pre- 
vertebral and  pretracheal  layers  and  follow  the  trachea  and  oesophagus  down  into  the 
chest.  Should  it  tend  outwardly  it  may  break  into  the  posterior  cervical  triangle 
between  the  prevertebral  and  superficial  layers  and  show  itself  above  the  clavicle. 


156  APPLIED    ANATOMY. 

Retropharyngeal  Abscess. — Pus  which  tends  to  point  into  the  pharynx  may  come 
from  disease  of  the  vertebrae,  in  which  case  it  is  posterior  to  the  prevertebral  fascia; 
or  it  may  originate  from  the  lymphatic  nodes  in  the  retropharyngeal  space. 

When  coming  from  caries  of  the  vertebrae,  it  may  point  either  in  the  pharynx 
or,  pushing  its  way  outward,  pass  behind  the  great  vessels  and  show  itself  behind 
the  outer  edge  of  the  sternomastoid  muscle.  I  have  seen  it  point  in  both  these 
places  in  the  same  case.  When  originating  in  the  retropharyngeal  space  it  lies  in 
front  of  the  prevertebral  fascia  and  behind  the  buccopharyngeal  fascia.  It  either 
points  forward  into  the  pharynx  or,  going  down,  follows  the  posterior  surface  of  the 
oesophagus  into  the  posterior  mediastinum.  It  may  also  perforate  the  oesophagus 
and  enter  its  lumen. 

Pus  in  the  Posterior  Cervical  Triangle. — If  above  the  prevertebral  layer  this 
bulges  directly  forward  and  tends  to  open  through  the  skin.  Its  progress  downward 
is  obstructed  by  the  attachment  of  the  superficial  layer  to  the  top  of  the  clavicle  as 
it  blends  with  the  prevertebral  layer.  If  pus  is  beneath  the  prevertebral  layer  it  may 
then  follow  the  brachial  plexus  and  subclavian  artery  down  beneath  the  clavicle  and 
appear  in  the  axilla.  The  attachments  of  the  costocoracoid  membrane  tend  to  direct 
the  pus  laterally  under  the  pectoralis  minor  muscle  into  the  axilla  rather  than  to  allow 
It  to  come  forward  on  the  anterior  portion  of  the  chest. 

LYMPHATICS  OF  THE  NECK. 

The  lymphatics  of  the  neck  are  both  superficial  and  deep.  The  superficial 
nodes  communicate  freely  with  and  end  in  the  deep  ones.  For  the  sake  of  conven- 
ience we  may  divide  them  into  a  transverse  set,  embracing  the  submental^  submaxillary, 
superficial  upper  cervical  (behind  the  angle  of  the  jaw),  posterior  auriciilar,  and 
occipital  nodes;  and  two  longitudinal  sets,  one  along  the  great  vessels  and  another,  a 
posterior  set,  in  the  posterior  cervical  triangle. 

The  Transverse  Lymphatics. — The  stibmental  nodes,  also  called  the  supra- 
hyoid, lie  beneath  the  chin  and  drain  the  region  of  the  lower  lip  and  chin  and  anterior 
part  of  the  floor  of  the  mouth.  These  will  be  enlarged  in  children  with  ulcerative  skin 
affections  of  these  regions.  They  may  also  be  involved  in  carcinoma  of  the  lower  lip, 
especially  if  near  the  median  line.  That  the  submental  nodes  drain  the  tissues  of  the 
anterior  portion  of  the  mouth  and  probably  the  tongue  itself  is  shown  by  Henry  T. 
Butlin  ("Surgery  of  Malignant  Disease,"  p.  153),  who  states  that  the  submental 
nodes  are  frequently  affected  in  carcinoma  of  the  tongue  when  its  tip  is  involved. 

The  submaxillary  nodes  are  beneath  the  body  of  the  mandible  in  the  sub- 
maxillary triangle.  They  drain  the  lips,  nose,  floor  of  the  mouth,  gums,  anterior 
portion  of  the  tongue  and  side  of  the  face.  These  are  the  nodes  most  frequently 
affected  in  carcinomatous  affections  of  the  lips  and  anterior  portion  of  the  tongue. 
Henry  T.  Butlin  ("Surgery  of  Malignant  Disease,"  p.  153)  calls  attention  to  the 
fact  that  in  malignant  disease  of  one  side  of  the  anterior  portion  of  the  tongue  the 
lymphatics  of  the  opposite  side  may  also  be  involved,  thus  showing  that  the  lym- 
phatics of  the  two  sides  of  the  tongue  freely  anastomose.  This  is  contrary  to  what 
exists  as  regards  the  arteries,  which  anastomose  hardly  at  all  across  the  median  line. 
He  also  states  that  one  or  more  of  the  lymphatic  nodes  is  frequently  imbedded  in  the 
substance  of  the  submaxillary  gland.  Therefore  the  submaxillary  gland  is  excised  at 
the  same  time  as  the  affected  lymphatic  nodes. 

The  superficial  tipper  cervical  {subparotid)  nodes  are  just  below  the  parotid 
lymphatics  and  behind  the  angle  of  the  jaw.  They  drain  tlie  region  embraced  by 
the  masseter  muscle  as  far  back  as  the  ear.  They  may  be  enlarged  in  affections  of 
the  skin  and  scalp  above.  Therefore  in  children  with  enlargement  of  these  nodes 
the  source  of  infection  should  be  sought  in  those  regions. 

The  poste7'ior  auricular  nodes  are  behind  the  ear  on  the  mastoid  process  and 
insertion  of  the  sternomastoid  muscle.  In  practice  they  are  encountered  as  small 
(i  cm.),  round  swellings  behind  the  ear,  which  are  usually  quite  tender  to  the  touch. 
This  is  probably  due  to  their  being  placed  on  a  hard,  bony  base.  When  enlarged 
they  are  often  the  subject  of  operations. 


THE    NECK. 


157 


The  superficial  occipital  yiodes  are  just  below  the  superior  curved  Hue  of  the 
occiput  oi"  a  little  lower  down  in  the  hollow  below  the  occiput  between  the  posterior 
edge  of  the  sternomastoid  and  anterior  edge  of  the  trapezius  muscles,  resting  on  the 
splenius.  These  are  the  nodes  that  are  enlarged  in  syphilis  and  are  to  be  searched 
for  in  endeavoring  to  establish  a  diagnosis. 

Superficial  and  Deep  Abodes.  — •  The  five  sets  of  nodes  just  described,  viz. ,  the 
submental,  submaxillary,  superficial  upper  cervical,  posterior  auricular,  and  superficial 
occipital,  are  all  regarded  as  superficial  nodes.  As  a  matter  of  fact  this  division  of  the 
lymphatic  nodes  into  superficial  and  deep  is  not  of  practical  value.  The  communica- 
tion between  the  various  nodes  is  quite  free.  Adjacent  nodes  communicate  and  the 
superficial  nodes  communicate  with  the  deep  ones  below. 

On  account  of  this  an  afTection  is  not  always  limited  to  a  single  node  but  often 
involves  those  to  each  side  and  those  lying  still  deeper.      In  the  submaxillary  region 


Posterior 
auricular  node 


Anterior 
auricular  node 


Occipital  node 


Superior   deep 
cervical  nodes 


Superficial 
cervical  nodes 


Fig.  i8i. — Superficial  lymphatic  vessels  and  nodes  of  head  and  neck;  semidiaerammatic.    (Piersol.) 

the  nodes  will  almost  certainly  be  found  to  lie  under  the  fascia  along  with  the  sub- 
maxillary gland.  When  the  occipital  nodes  are  enlarged  they  may  not  only  be 
found  in  the  space  already  described  but  also  on  the  adjacent  trapezius  and  sterno- 
mastoid muscle  and  even  beneath  the  outer  edge  of  the  trapezius  below  the  deep 
fascia. 

The  Longitudinal  Lymphatics. — These  are  along  the  great  vessels, — the 
anterior  cervical  lymphatics, — and  in  the  posterior  cervical  triangle. 

The  anterior  cervical  lymphatics  is  the  name  given  to  those  which  tend  to  show 
in  the  anterior  cervical  triangle  either  beneath  or  in  front  of  the  sternomastoid 
muscle,  between  it  and  the  median  line.  There  are  some  nodes  in  the  median  line 
but  they  are  almost  all  deep  down  in  the  neck  above  the  sternum.  The  other  nodes 
may  be  either  superficial  or  deep,  mostly  deep,  along  the  edge  of  the  sternomastoid 


T'^y  ^^^^^         APPLIED    ANATOMY.  ^^^^^^^^^H 

muscle.  They  follow  the  sheath  of  the  vessels.  This  is  a  very  extensive  chain  of 
nodes.  They  may  extend  in  all  directions.  As  regards  depth  they  may  be  on  the 
deep  fascia  along  the  edge  of  the  sternomastoid  or  following  the  external  jugular 
vein.  If  deeper  they  follow  the  internal  jugular  vein  and  carotid  artery  directly 
up  to  the  base  of  the  skull,  also  behind  and  below  the  mastoid  process  and  along- 
side of  the  transverse  process  of  the  atlas  (first  cervical  vertebra).  They  extend 
under  the  sternomastoid  posteriorly,  deep  in  the  suboccipital  region.  Should 
they  be  enlarged  downward  they  will  protrude  behind  the  posterior  edge  of  the 
sternomastoid  into  the  posterior  cervical  triangle;  if  anteriorly  they  will  follow  it 
down  into  the  space  of  Burns  in  front  of  the  trachea  and  thence  into  the  superior 
mediastinum. 

T\\&  posterior  cervical  nodes  show  behind  the  posterior  edge  of  the  sternomastoid, 
along  the  edge  of  the  trapezius,  and  also  above  tne  clavicle.  They  not  infrequently 
fill  the  posterior  cervical  triangle  and  extend  beneath  the  muscles  on  each  side. 

Below  they  may  be  continuous  with  enlarged  nodes  in  the  axilla  and  extend 
anteriorly  under  the  sternomastoid  into  the  pretracheal  region  and  mediastinum. 
They  are  frequently  excised  for  both  tuberculosis  and  carcinoma.  In  so  doing 
particular  care  is  to  be  taken  on  account  of  the  trans\'ersalis  colli  and  suprascapular 
arteries  and  veins,  with  which  they  may  lie  in  contact,  as  well  as  the  terminal  por- 
tion of  the  external  jugular. 

Postpharyngeal  Nodes. — In  ihe  retropharyngeal  space,  toward  the  sides, 
between  the  buccopharyngeal  fascia  in  front  and  the  prevertebral  fascia  behind  are 
located  one  or  two  nodes  (see  buccopharyngeal  fascia,  page  153,  and  retropharyn- 
geal abscess,  page  156).  They  seem  to  be  the  starting  point,  sometimes,  of  retro- 
pharyngeal abscess.  They  do  not  appear  to  get  enlarged  and  project  into  the 
pharynx  as  tumors,  as  might  be  expected,  so  that  they  are  not  subjected  to  any 
surgical  procedures. 

Operating  for  the  Removal  of  Enlarged  Cervical  Nodes. — This  opera- 
tion may  be  one  of  the  most  serious  in  surgery.  Sir  Frederick  Treves  says  :  "  An 
operation  of  this  kind  should  not  be  undertaken  unless  the  surgeon  has  perfect  con- 
fidence in  his  practical  knowledge  of  the  anatomy  of  the  neck.  Scarcely  an  instance 
can  be  cited  in  the  range  of  operative  surgery  where  a  knowledge  of  the  structure 
and  of  relations  is  more  essential  than  in  these  excisions."  The  main  difficulties 
encountered  are  in  the  avoidance  of  nerves  and  the  control  of  hemorrhage.  Air 
may  enter  the  veins  and  cause  death,  and  the  thoracic  duct  may  be  wounded.  The 
latter  accident  sometimes  results  fatally.  The  difficulty  of  the  operation  will  de- 
pend on  the  size  and  number  of  the  nodes,  their  location,  and  the  character  of  the 
inflammation  or  other  changes  they  have  undergone.  In  an  early  stage  the  nodes 
may  be  lying  loose  in  the  tissues  and  can  be  readily  turned  out  when  once  exposed. 
Later  they  may  be  matted  to  the  surrounding  structures  by  inflammatory  deposits 
and  then  their  separation  is  a  matter  of  difficulty  and  danger. 

The  skin  incisions  may  be  either  longitudinal  or  more  or  less  transverse.  The 
longitudinal  incisions  are  usually  along  either  the  anterior  or  posterior  border  of 
the  sternomastoid  muscle,  or  the  anterior  edge  of  the  trapezius.  The  transverse 
incision  may  be  either  opposite  the  hyoid  bone — when  it  may  be  prolonged  around 
the  angle  of  the  jaw  and  up  to  the  mastoid  process  and  over  the  suboccipital  glands, 
or  above  the  clavicle. 

As  the  skin  and  superficial  structures  are  cut  and  the  deep  fascia  opened, 
the  superficial  veins  will  be  cut,  hence  the  first  anatomical  fact  to  be  borne  in  mind 
is  the  probable  location  of  the  veins.  The  most  important  of  these  is  the  external 
jugular.  The  internal  jugular  below  the  hyoid  bone  lies  under  the  sternomastoid 
muscle  and  therefore  is  protected  until  the  deeper  dissection  is  begun.  The  external 
jugular  runs  about  in  a  line  from  the  angle  of  the  jaw  to  the  middle  of  the  posterior 
edge  of  the  sternomastoid  muscle  and  thence  downward  to  about  the  middle  of  the 
clavicle.  Therefore  an  incision  along  the  posterior  edge  of  the  sternomastoid  will 
divide  it  at  about  the  middle  of  the  muscle,  and  the  surgeon  should  be  prepared  to 
guard  against  an  undue  loss  of  blood  when  it  is  cut.  Opening  into  the  external 
jugular  posteriorly  between  the  middle  of  the  sternomastoid  muscle  and  the  clavicle 
below  are  the  posterior  jugular,  the  transverse  cervical,  and  the  suprascapular  veins. 


THE   NECK.  159 

These  latter  open  into  the  external  jugular  i  or  2  cm.  above  the  clavicle  and  are 
almost  certain  to  be  cut  in  operations  in  the  supraclavicular  fossa.  An  incision 
along  the  anterior  edge  of  the  sternomastoid  low  down  will  cut  the  anterior  jugular 
vein  a  short  distance  above  the  sternum  as  it  winds  beneath  the  sternomastoid  to 
empty  into  the  external  jugular.  An  incision  along  the  anterior  border  of  the 
sternomastoid  from  its  middle  up  is  bound  to  cause  free  hemorrhage.  The  external 
jugular  behind  the  angle  of  the  jaw  communicates  with  the  facial,  which  empties  into 
the  internal  jugular;  hence  division  of  the  external  jugular  at  this  point  also  drains 
the  blood  almost  directly  from  the  internal  jugular.  A  carelessly  deep  incision  may 
wound  the  internal  jugular  itself  in  the  region  posterior  to  the  hyoid  bone.  The 
internal  jugular  is  more  superficial  at  this  point  than  it  is  lower  down.  The  temporo- 
maxillary  and  posterior  auricular  veins  will  also  be  cut  behind  the  ramus  of  the  jaw. 

Not  only  are  veins  cut  but  also  nerves.  The  middle  of  the  posterior  edge 
of  the  sternomastoid  is  the  point  of  departure  of  several  nerves.  The  superficial 
cervical  runs  directly  transversely  inward  toward  the  thyroid  cartilage.  The  auricu- 
laris  magnus  goes  up  to  the  lobe  of  the  ear,  and  the  occipitalis  minor  follows  the 
posterior  edge  of  the  muscle  up  to  the  occiput.  These  three  nerves  are  nerves  of  sen- 
sation and  if  they  are  divided  only  a  certain  amount  of  temporary  anaesthesia  will  be 
produced  over  the  parts  they  supply,  hence  their  division  is  not  a  matter  of  much 
moment.  The  auricularis  magnus  is  the  largest  of  the  three.  The  descending 
branches  of  the  cervical  plexus,  which  leave  the  posterior  edge  of  the  sternomastoid 
muscle  immediately  below  the  nerves  just  mentioned,  proceed  down  under  the  deep 
fascia  and  will  be  seen  only  in  a  deeper  dissection.  The  nerve  which  it  is  absolutely 
important  to  avoid  is  the  spinal  accessory.  This  enters  the  sternomastoid  muscle 
on  its  under  surface  some  little  distance  back  of  its  anterior  edge  and  3  to  5  cm. 
below  the  mastoid  process.  It  sends  a  branch  to  the  muscle  and  leaves  its  posterior 
edge  about  its  middle.  It  then  passes  downward  and  outward  across  the  posterior 
cervical  triangle  under  the  deep  fascia  to  enter  the  deep  surface  of  the  trapezius.  If 
this  nerve  is  divided,  paralysis  of  the  trapezius  will  certainly  follow  and  as  it  is  a 
motor  nerve  the  shoulder  of  that  side  will  drop  considerably.  This  will  be  a  perma- 
nent deformity  because  motor  nerves  do  not  seem  to  have  their  functions  restored 
by  time  as  so  usually  occurs  when  the  nerves  of  sensation  are  divided. 

If  the  nodes  to  be  removed  are  superficial  ones  there  are  no  other  structures  to 
be  feared  and  the  operation  will  be  an  easy  one.  If  they  lie  deeper,  then  the  sheath 
of  the  sternomastoid  muscle  is  to  be  divided  and  the  muscle  pulled  outward.  Just 
above  the  level  of  the  cricoid  cartilage  a  small  artery,  the  sternomastoid  branch  of 
the  superior  thyroid,  enters  the  muscle  and  it  will  be  divided.  As  the  sternomastoid 
is  raised  and  pulled  outward  care  must  be  taken  to  avoid  wounding  the  spinal 
accessory  nerve.  As  this  nerve  enters  the  muscle  from  3  to  5  cm.  below  the  mastoid 
process  and  some  distance  back  from  the  edge  of  the  muscle,  if  it  is  necessary  to 
divide  the  muscle  it  is  best  done  high  up  above  the  entrance  of  the  nerve,  or  low 
down.  By  so  doing  the  nerve  supply  (from  the  spinal  accessory)  and  blood  supply 
are  not  interfered  with  and  the  function  of  the  muscle  is  not  so  much  impaired  as 
it  would  be  if  divided  near  the  middle.  The  nodes  not  only  possess  their  own 
capsule  but  also  a  covering  from  the  connective  tissue  in  which  they  lie.  There- 
fore to  remove  them  they  must  be  detached  and  separated  from  it  usually  by  blunt 
dissection.  When  these  strands  of  fibrous  tissue  from  the  nodes  to  the  surrounding 
parts  are  strong  they  have  to  be  caught  with  forceps  and  cut.  They  are  to  be 
clamped,  to  avoid  possible  bleeding.  When  the  angle  of  the  jaw  is  reached  the 
communicating  branch  between  the  facial  and  external  jugular  veins  must  be 
clamped  and  cut.  The  parotid  gland  is  to  be  pulled  upward  and  inward.  The 
nodes  may  stick  to  the  jugular  vein  and  carotid  artery.  The  vein  is  on  the  outside 
and  is  likely  to  be  the  first  encountered.  When  distended  it  overlies  the  artery. 
If  collapsed  its  presence  may  not  be  suspected.  Feel  for  the  pulsation  of  the  carotid 
artery  and  avoid  the  structure  just  to  its  outer  side.  The  jugular  vein  may  be  so 
involved  in  the  mass  as  to  necessitate  its  removal.  In  such  a  case  remember  that 
posteriorly  between  it  and  the  carotid  artery  is  the  pneumogastric  nerve. 

The  sympathetic  nerve  lies  deeper  in  the  fascia  toward  its  posterior  surface  and 
is  not  so  likely  to  be  wounded.      Its  superior  cervical  ganglion  lies  opposite  the 


APPLIED    ANATOMY. 

second  and  third  vertebrae.  Working  still  higher,  the  transverse  process  oi  tf^ 
atlas  or  first  cervical  vertebra  will  be  felt  and  seen  below  and  to  the  inner  side  of  the 
mastoid  process.  The  connective  tissue  adherent  to  the  nodes  is  attached  to  this 
transverse  process  and  may  have  to  be  cut  loose  or  scraped  away.  In  doing  so 
keep  to  the  outer  edge  because  the  jugular  vein  and  internal  carotid  artery  lie  on  its 
anterior  surface. 

Beneath  the  sternomastoid  runs  the  anterior  scalene  muscle  and  on  it,  coming 
from  the  third,  fourth,  and  fifth  cervical  nerves,  is  the  phrenic  nerve;  so  that  it  is 
not  permitted  to  dig  into  and  disturb  the  muscular  mass  to  the  outer  side  of  the 
common  carotid  artery  on  which  these  nodes  frequently  lie. 

In  operating  in  the  submental  regio7i  there  is  nothing  to  fear.  The  space 
between  the  two  anterior  bellies  of  the  digastric  muscles  on  the  sides,  the  hyoid 
bone  below,  and  down  to  the  anterior  surface  of  the  mylohyoid  muscle  beneath,  can 
be  cleared  out  with  impunity. 


N.  occipitalis  major 
Art.  occipitalis 

Complexus 

Sternomastoid 

Splenius 

Levato"-  scapulae 


Trapezius 

Complexus 

Obliquus  superior 

Splenius 

Trachelomastoid 

Art.  occipitalis 

Transverse  process,  atlas 

Art.  vertebralis 

Rectus  capitis  posticus  major 

Rectus  capitis  posticus  minor 

Obliquus  inferior 

Levator  scapulae 

Complexus 

Splenius 


Rhomboideus 
minor 


Rhomboideus 
major 


Fig.  182. — Superficial  and  deep  structures  of  the  back  of  the  neck,  showing  the  suboccipital  triangle, 
formed  by  the  rectus  capitis  posticus  major,  obliquus  superior  and  obliquus  inferior:  the  suboccipital  nerve 
emerges  from  just  beneath  the  art.  vertebralis. 

In  the  submaxillary  region  remember  that  the  fascia  covering  the  submaxillary 
gland  is  thin,  so  that  the  gland  will  probably  be  exposed  as  soon  as  the  superficial 
structures  are  raised.  As  the  facial  artery  and  vein  cross  the  mandible  just  in  front 
of  the  masseter  muscle,  the  vein  is  posterior.  The  artery  goes  under  the  gland  and 
is  adherent  to  it,  so  that  as  the  gland  is  raised  the  artery  is  brought  up  also.  The 
facial  and  lingual  veins  usually  empty  into  the  internal  jugular,  but,  as  shown  in  Fig. 
168,  they  may  receive  a  communicating  branch  from  the  external  jugular  and  the 
anterior  jugular  and  continue  down  as  the  anterior  jugular  to  empty  into  the 
external  jugular  low  down  in  the  neck,  beneath  the  sternomastoid  muscle.  The 
hypoglossal  nerve  will  be  seen  lying  on  the  hyoglossus  muscle,  but  it  is  readily 
avoided.  The  lingual  artery  is  beneath  the  hyoglossus  muscle  anteriorly  but  both  it 
and  the  facial  must  be  looked  for  as  one  nears  the  posterior  belly  of  the  digastric. 

In  the  lower  cervical  region,  opposite  the  cricoid  cartilage,  the  omohyoid  muscle 
will  be  met.  It  will  sometimes  be  necessary  to  divide  it.  The  sternohyoid  and  sterno- 
thyroid muscles  and  the  thyroid  gland  are  to  be  drawn  inward  and  the  sternomastoid 
outward.      One  should  always  keep  away  from  the  thyroid  gland,  as  the  recurrent 


THE   NECK.  i6i 

laryngeal  nerve  runs  behind  it  and  on  the  oesophagus  near  the  trachea.  Cutting  it 
will  probably  cause  a  permanent  alteration  in  the  voice.  If  the  internal  jugular  vein 
has  been  removed,  as  it  may  be  on  one  side,  but  not  on  both,  beneath  it  one  is 
liable  to  encounter  the  inferior  thyroid  artery  below  Chassaignac's  tubercle  on  the 
sixth  cervical  vertebra,  and  further  out  the  phrenic  nerve  on  the  scalenus  anticus  mus- 
cle, and  lower  down  the  transverse  cervical  and  suprascapular  arteries.  The  inferior 
thyroid  veins  usually  run  downward  to  empty  into  the  innominate  veins,  but  the 
lower  portion  of  the  anterior  jugular  vein  and  the  middle  thyroid  veins  will  probably 
have  to  be  ligated.  The  course  of  the  various  veins  is  quite  irregular  and  large 
venous  branches  may  be  encountered  at  any  place. 

In  the  posterior  cervical  triangle  the  spinal  accessory  nerve  must  be  avoided  as 
it  runs  down  and  back  from  the  middle  of  the  posterior  edge  of  the  sternomastoid 
muscle.  The  external  jugular,  posterior  jugular,  transverse  cervical,  and  supra- 
scapular veins  may  all  require  ligation.  Beneath  the  deep  fascia  (superficial  layer) 
are  the  descending  or  supraclavicular  branches  of  the  cervical  plexus  from  the  third 
and  fourth  cervical  nerves.  Care  should  be  taken  not  to  mistake  them  for  the 
spinal  accessory  nerve.  If  the  nerve  has  been  divided  it  should  be  sutured  together 
again  at  the  completion  of  the  operation.  It  is  hardly  necessary  to  caution  against 
wounding  the  subclavian  vein;  it  is  in  front  of  the  anterior  scalene  muscle.  The 
artery  is  behind  the  muscle.  Do  not  dig  under  it.  It  rests  on  the  pleura,  a  wound  or 
tear  of  which  may  mean  a  septic  pleurisy  and  death.  In  the  angle  formed  by  the 
junction  of  the  internal  jugular  vein  and  subclavian  on  the  left  side  is  the  thoracic 
duct.  If  wounded  death  may  ensue  through  persistent  leakage  of  lymph,  but  not 
infrequently  healing  eventually  occurs.  Wounding  of  the  corresponding  lymphatic 
duct  on  the  right  side  is  not  considered  so  serious,  the  chyle  being  carried  by  the  left 
duct.  The  cords  of  the  brachial  plexus  run  down  and  across  the  posterior  cervical 
triangle  above  the  subclavian  artery,  but  a  little  care  will  enable  one  to  avoid  them. 
This  is  one  of  the  regions  of  the  body  in  which  exact  surgery  is  essential. 

OPERATIONS  ON  THE  AIR-PASSAGES. 

The  pharynx  may  be  opened  just  below  the  hyoid  bone, — subhyoidean  pharym- 
gotomy.  The  larynx  may  be  opened  in  the  median  line, — thyrotomy.  The  crico- 
thyroid membrane  may  be  opened, — laryngotomy.  The  trachea  may  be  opened, — 
tracheotoyny. 

Subhyoidean  pharyngotomy  is  the  entering  of  the  pharynx  by  means  of  an 
incision  below  the  hyoid  bone.  This  is  an  extremely  rare  operation.  It  may  be 
performed  for  the  removal  of  foreign  bodies  or  tumors.  The  incision  may  be  made 
just  below  the  hyoid  bone  and  parallel  to  its  border.  This  will  divide  the  com- 
mencement of  the  anterior  jugular  vein,  perhaps  near  the  median  line,  perhaps  toward 
the  side.  A  transverse  vein  usually  runs  from  one  anterior  jugular  vein  to  the  other 
across  the  median  line  at  this  point.  Attached  to  the  hyoid  bone  nearest  to  the 
median  line  is  the  sternohyoid  muscle,  then  farther  out  the  omohyoid,  and  still  farther 
out  the  thyrohyoid.  A  small  artery,  the  thyrohyoid,  a  branch  of  the  superior  thyroid, 
or  sometimes  of  the  lingual,  will  be  divided. 

The  thyrohyoid  membrane  being  incised,  access  is  obtained  to  the  fatty  tissue 
at  the  base  of  the  epiglottis.  If  the  incision  is  carried  directly  backward  the  epiglottis 
will  be  cut  through  at  its  base.  If,  however,  it  is  kept  close  to  the  hyoid  bone  and 
made  upward,  the  pharynx  will  be  entered  in  front  of  the  epiglottis  and  at  the 
root  of  the  tongue.  If  the  incision  is  carried  too  far  toward  the  sides  the  superior 
thyroid  artery  and  even  the  external  carotid  itself  will  be  cut;  if  carried  too  low  down 
on  the  thyrohyoid  membrane,  then  the  superior  laryngeal  artery  and  nerve  may  both 
be  wounded.      Attention  has  already  been  called  to  the  thyrohyoid  branch. 

Thyrotomy  is  the  division  of  the  thyroid  cartilage  in  the  median  line.  The 
sternohyoid  muscles  almost  touch  in  the  median  line.  The  division  should  be 
exactly  in  the  median  line.  This  will  avoid  wounding  the  anterior  jugular  veins.  If 
not  in  the  median  line  the  incision  will  wound  one  of  the  vocal  cords.  Impairment 
of  the  voice  certainly  follows  this  operation;  it  is  only  performed  for  the  removal  of 
foreign  bodies  or  growths. 


l62 


APPLIED    AN  ATOM  \^. 


Laryngotomy  is  the  opening  of  the  cricothyroid  membrane.  It  is  rarely 
done,  but  it  is  of  service  in  cases  of  choking  from  obstruction  of  the  larynx,  foreign 
bodies,  etc. 

There  is  not  sufficient  room  between  the  cricoid  and  thyroid  cartilages  to  do 
this  operation  properly  until  puberty  has  been  reached  and  the  larynx  has  enlarged. 
The  cricoid  cartilage  is  narrow  in  front  but  wide  behind.  Its  upper  edge  rises  rapidly 
as  it  passes  backward,  forming  an  upper  crescentic  border,  the  concavity  being 
upward.  The  lower  edge  of  the  thyroid  is  concave  downward.  Thus  the  two  edges 
make  an  oval  opening  in  front  which  in  children  is  too  small  to  hold  the  tracheotomy 
tube.  The  nearness  to  the  vocal  cords  is  also  a  serious  objection.  Performing  a 
laryngotomy  is  the  easiest  and  quickest  way  to  enter  the  air-passages.  Both  the 
thyroid  and  cricoid  cartilages  in  the  median  line  are  practically  subcutaneous.  A  lon- 
gitudinal incision  of  the  skin  is  usually  advised,  after  which  a  transverse  incision  is  em- 
ployed for  opening  the  cricothyroid  membrane.  The  tube  is  to  be  shorter  than  the  one 
ordinarily  used  for  tracheotomy.  The  cricothyroid  artery,  running  across  the  mem- 
brane, is  usually  too  insignificant  to  cause  any  trouble ;  it  is  nearer  the  thyroid  cartilage, 
therefore  the  cut  through  the  membrane  should  be  close  to  the  cricoid  cartilage. 

Tracheotomy  is  the  opening  of  the  trachea.  There  are  two  varieties,  the 
high  and  the  low,  according  as  the  tube  is  inserted  above  or  below  the  isthmus  of 
the  thyroid  gland.  When  in  the  adult  male  the  neck  is  in  line  with  the  axis  of  the 
body  the  lower  border  of  the  cricoid  cartilage  is  about  4  cm.  (ij4  in.)  above  the 
sternum.  When  the  head  is  tilted  far  back  the  larynx  is  drawn  upward  and  the 
lower  border  of  the  cricoid  is  6  cm.  (about  2}^  in.)  above  the  sternum.  Hence  in 
doing  a  tracheotomy  the  head  is  to  be  tilted  far  back.  The  total  length  of  the 
trachea  is  10  to  12  cm.  (Morris,  Hensman),  beginning  opposite  the  sixth  cervical 
vertebra, — upper  border  in  the  child  and  lower  in  adults, — and  ending  opposite  the 
fifth  dorsal.  About  half  of  it  is  above  and  half  below  the  top  of  the  sternum.  It  is 
composed  of  14  to  20  rings.  In  the  adult  the  isthmus  of  the  thyroid  gland  covers 
the  second,  third,  and  fourth  rings.     There  are  about  eight  rings  above  the  sternum. 

According  to  Symington  and  Guersant  (Treves)  the  diameter  of  the  trachea  is 
about  as  follows: 


1)4  io    2  years 5  mm- 

2      to    4  years 6  mm. 

4      to    8  years 8  mm. 

8      to  12  years 10  mm. 

12      to  15  years 12  mm. 

Adults 12-15  mm. 

A  knowledge  of  the  size  of  the  trachea  is  necessary  in  order  to  select  a  trache- 
otomy tube  of  a  size  suitable  to  the  particular  case.  The  liability  is  to  select  too 
large  a  tube  for  young  children,  particularly  infants.  If  this  is  done  it  may  be  very 
difficult  to  introduce  the  tube,  or  the  trachea  may  even  be  torn  in  the  attempt.  In 
operating,  an  incision  2. 5  to  3  cm.  long  is  to  be  made  in  the  median  line.  This 
may  cut  the  anterior  jugular  vein.  If  carried  near  to  the  sternum  it  will  certainly 
divide  the  communicating  branch  between  the  anterior  jugulars  at  that  point.  The 
top  of  the  incision  in  a  child  will  be  over  the  cricoid  cartilage,  and  as  soon  as  the  skin 
has  been  divided  the  finger  is  to  be  inserted  and  the  cricoid  cartilage  felt  and  recog- 
nized. This  will  show  how  deep  the  trachea  lies.  In  very  young  children  the 
isthmus  of  the  thyroid  gland  is  liable  to  come  up  to  the  cricoid  cartilage  and  the  dif- 
ficulty of  displacing  it  far  enough  down  to  allow  the  tube  to  be  inserted  is  such  that 
it  may  be  best  to  divide  it.  Therefore  after  the  skin  and  deep  fascia  have  been  divided 
and  the  cricoid  recognized  by  the  finger  the  soft  tissues  covering  the  trachea  imme- 
diately below  the  cricoid  are  grasped  on  each  side  with  a  haemostatic  forceps  and 
divided  between  them.  These  tissues  may  embrace  the  isthmus  of  the  thyroid  gland, 
the  edges  of  the  sternohyoid  muscles,  some  veins,  branches  from  the  superior  and 
inferior  thyroids,  and  the  fascia  covering  the  gland  and  overlying  the  trachea. 

The  trachea  should  be  cleared  before  opening  it.  A  sharp  hook  is  inserted  into 
the  cricoid  cartilage  to  steady  it  and  an  incision  is  made  into  the  trachea  from  below 
upward.     In  making  this  incision  the  utmost  care  must  be  taken  not  to  cut  through 


THE    NECK. 


163 


the  trachea  and  wound  the  oesophagus  behind.  The  trachea  of  a  child  is  not  the  hard 
resisting  structure  of  the  adult.  It  is  a  soft  tender  tube  easily  compressed  and  readily 
torn  by  roughness,  or  punctured  with  a  knife.  Forceps  do  not  readily  hold  in  it  and 
stitches  through  it  are  liable  to  tear  out.  Only  the  very  tip  of  the  point  of  the  knife 
should  be  allowed  to  enter  the  tube.  The  utmost  care  must  be  taken  to  keep  in  the 
median  line.  This  is  to  be  accomplished  by  using  the  cricoid  cartilage  as  a  guide 
and  by  seeing  that  the  position  of  the  head  is  straight.  Cutting  to  either  side  of  the 
trachea  will  cause  wounding  of  the  common  carotid  arteries.  Below  the  isthmus  of  the 
thyroid  gland  and  running  down  on  the  trachea  are  the  inferior  thyroid  veins.  The 
superior  and  middle  thyroid  veins  empty  into  the  internal  jugular  vein,  but  the 
inferior  thyroids  go  downward  to  empty  into  the  innominate.  These  veins  will  be  cut 
if  a  low  tracheotomy  is  done.  In  the  infant  the  innominate  artery  and  sometimes, 
though  rarely,  the  left  carotid  encroach  on  the  suprasternal  notch  and  may  be  wounded 
if  the  incision  is  carried  too  low.     The    left   innominate  vein  as  it  crosses  to  the 


Lingual  and  facial  veins 


Interna]  jugular  vein 


Middle  thyroid  veins 


Sternohyoid  muscle 
Sternomastoid  muscle 
Sternothyroid  muscle 
Anterior  jugular  vein 
Inferior  thyroid  vein 


drawn  back 


—  Hyoid  bone 

Thyroid  cartilage 

Cricothyroid  muscle 

Sternohyoid  muscle 

Sternothyroid  muscle 

Superior  thyroid  artery  and  vein 

Cricoid  cartilage 
_  Thyroid  gland 
^  Inferior  thyroid  artery 


Inferior  thyroid  vein 

Sternomastoid  muscle 

Trachea 

Communicating  branch  between  the 

anterior  jugular  veins 


Fig.  183. — Dissection  showing  the  parts  involved  in  operations  on  the  thyroid  gland  and  air-passages. 

right  side  is  liable,  especially  in  very  young  children,  to  show  quite  plainly  above  the 
sternum  and  would  certainly  be  cut  if  the  deep  incision  was  carried  as  far  down  as 
the  top  of  the  sternum.  An  anomalous  artery,  the  thyroidea  ima,  a  branch  of  the 
innominate,  sometimes  passes  upward  on  the  trachea.  On  account  of  the  presence 
of  all  these  vessels  it  is  not  allowable  to  do  any  cutting  of  the  deep  parts  just  above 
the  sternum;  they  are  simply  to  be  depressed  by  blunt  dissection  and  kept  out  of 
the  way  with  retractors  while  the  trachea  is  being  incised.  The  cricoid  cartilage  is 
never  to  be  incised.  It  is  far  more  firm  and  resistant  than  the  trachea  and  it  serves 
to  keep  the  trachea  from  collapsing.  The  proximity  of  the  tracheotomy  tube  to  the 
vocal  cords  would  result  in  interference  with  their  function. 

The  method  of  Bose  consists  in  dividing  the  fascia  OA^erlying  the  trachea  near 
the  cricoid  cartilage  and  pushing  it  down,  carrying  the  isthmus  and  veins  with  it, 
and  introducing  the  tube  into  the  space  so  cleared.  This  is  so  difficult  that  it  is 
better  to  divide  the  isthmus,   as  already  described. 


OPERATIONS  ON  THE  THYROID  GLAND. 

The  operations  which  are  done  on  the  thyroid  gland  are  ligation  of  its  arterial 
supply  and  complete  or  partial  removal.  These  necessitate  a  knowledge  particularly 
of  its  blood  supply  and  structure. 

The  thyroid  gland  cov&v&Vs,  of  an  isth?mis  and  two  lateral  lobes.      The  isthmus 


164 


APPLIED    ANATOMY. 


crosses  the  second,  third,  and  fourth  tracheal  rings  in  the  adult.      In  children  it  may' 
approach  nearer  to  the  cricoid  cartilage. 

The  lateral  lobes  lie  under  the  sternohyoid  and  the  sternothyroid  muscles. 
They  rise  as  high  as  the  oblique  line  on  the  sides  of  the  thyroid  cartilages  which 
marks  the  insertion  of  the  sternothyroid  muscles.  The  lobes  descend  to  the  level 
of  the  sixth  ring  of  the  trachea,  which  is  two  rings  below  the  isthmus,  about  two 
centimetres  above  the  sternum.  The  inferior  constrictor  of  the  pharynx  is  beneath 
the  gland.  The  thyroid  gland  is  covered  by  the  pretracheal  fascia  and  possesses 
a  capsule  of  its  own  besides.  This  fascia  envelops  the  gland  and  its  capsule,  and 
from   its   posterior  surface  is  prolonged  down   on  the  trachea   and  envelopes  the 


Omohyoid  muscle 
Sternothyroid  muscle 

Sternohyoid  muscle 


Sup.  parathyroid 

Inf.  parathyroid 
Trachea 
Sternothyroid  muscle 


Stemomas- 
toid  muscle 


CEsophagus 
Omohyoid  muscle 

Inferior  thyroid  artery 

Recurrent  laryngeal  nerve 
Middle  thyroid  vein 
Inferior  thyroid  veins 

Sternohyoid  muscle 


Fig.  184. — Excision  of  the  thyroid  gland. 


vessels  coming  to  and  leaving  the  gland.  Therefore  we  might  say  that  the  inferior 
thyroid  veins  are  in  the  pretracheal  fascia. 

As  the  fascia  leaves  the  gland  at  the  sides  one  portion  of  it  blends  with  and 
helps  to  form  the  sheath  of  the  vessels.  The  other  or  deeper  portion  continues 
around  the  pharynx  and  oesophagus,  forming  the  buccopharyngeal  fascia.  In  freeing 
the  gland  and  its  capsule  from  the  overlying  pretracheal  fascia  care  must  be  taken, 
as  pointed  out  by  James  Berry  ("  Diseases  of  the  Thyroid  Gland,"  p.  269),  not  to 
be  led  by  this  fascia  too  far  posteriorly  and  therefore  wound,  as  has  been  done,  the 
pharynx  or  trachea. 

The  veins  of  the  gland  are  more  prominent  and  dangerous  than  the  arteries. 
They  ramify  beneath  the  capsule  and  as  long  as  the  capsule  is  not  torn  the  bleeding 
is  slight.  The  arteries  of  the  thyroid  gland  are  the  superior  and  inferior  thyroids 
and  sometimes  the  thyroidea  ima.     The  superior  thyroid  comes  off  the  external 


THE   NECK.  165 

carotid  just  above  the  bifurcation.  It  rises  almost  to  the  greater  horn  of  the  hyoid 
bone  and  then  descends  to  the  thyroid  gland,  which  reaches  to  the  level  of  the  oblique 
line  on  the  thyroid  cartilage;  it  supplies  the  upper  portion  of  the  gland,  particularly 
the  anterior  portion,  but  also  sends  a  branch  down  the  posterior  surface.  The 
vessels  crossing  the  median  line,  contrary  to  what  is  often  the  case  in  the  arteries  of 
the  lip  and  even  the  scalp,  are  very  small.  The  superior  thyroid  is  superficial  and 
presents  no  special  difhculty  in  ligation.  The  vein  runs  beneath  it  on  its  course  to 
the  internal  jugular.  The  inferior  thyroid  artery,  a  branch  of  the  thyroid  axis, 
crosses  behind  the  common  carotid  artery  about  the  level  of  the  seventh  cervical 
vertebra,  about  on  a  line  with  the  lower  edge  of  the  isthmus.  It  enters  the  gland 
from  the  side  and  not  from  below  and  ramifies  on  its  posterior  surface  often  as  a 
single  large  trunk  beneath  the  capsule  giving  off  branches  to  the  parenchyma. 
Usually  it  is  in  front  of  the  recurrent  laryngeal  nerve,  but  the  middle  cervical  gan- 
glion of  the  sympathetic  lies  on  it.  Sometimes  the  artery  breaks  into  branches  before 
it  enters  the  gland.  In  such  cases  the  recurrent  laryngeal  nerve  may  run  between 
these  branches  and  so  be  injured  in  removing  the  gland. 

The  thvroidca  ima  artery  when  present  enters  the  gland  from  below,  coming  up 
on  the  trachea  usually  from  the  innominate,  in  which  case  the  innominate  is  apt  to 
come  of?  more  to  the  left  side  and  so  bring  the  common  carotid  closer  to  the  trachea 
than  usual.      It  may  also  spring  from  the  aorta  or  from  the  right  carotid  artery. 

The  Veins. — There  are  three  sets  of  veins,  a  superior,  a  middle,  and  an  inferior 
thyroid,  and,  as  Kocher  has  pointed  out,  an  accessory  thyroid  between  the  middle 
and  inferior  ones.  The  veins  ramify  under  the  capsule  and  form  a  plexus,  which 
in  goitre  is  much  enlarged  and  communicates  freely  across  the  median  line  at  the 
upper  and  lower  portions  of  the  isthmus.  The  superior  and  middle  thyroids  pass 
outward  to  empty  into  the  internal  jugular.  Still  lower  is  the  accessory  inferior  thy- 
roid, which  may  empty  into  the  internal  jugular,  as  do  the  two  above  it,  or  it  may  pass 
down,  as  does  the  inferior  thyroid  vein,  and  empty  into  the  innominate.  The  inferior 
thyroid  vein  does  not  follow  the  artery  of  the  same  name  but  with  its  fellow  of  the 
opposite  side  passes  directly  downward  in  front  of  the  trachea  to  empty  into  the 
innominate  vein.  Its  importance  in  operations  on  the  trachea  has  already  been  alluded 
to  in  speaking  of  tracheotomy. 

In  removing  the  gland  the  superior  thyroid  artery  is  found  at  the  upper  outer 
angle,  the  ligature  should  be  placed  sufficiently  far  out  to  include  the  branch  to  the 
posterior  surface  of  the  gland.  In  ligating  the  inferior  thyroid  arteries  they  are  to 
be  sought  at  the  lower  portion  of  the  sides  of  the  gland  and  are  to  be  ligated  either 
close  to  the  gland  or  isolated  by  pulling  the  carotid  artery  outward,  and  tied  as  they 
make  the  bend  at  the  edge  of  the  anterior  scalene  muscle.  Between  these  two 
points  lies  the  recurrent  laryngeal  nerve,  usually  behind  the  artery.  Halsted  advises 
that  each  separate  branch  be  ligated  as  it  enters  the  gland  to  avoid  those  supplying 
the  parathyroids.  The  gland  is  covered  by  the  omohyoid,  sternohyoid,  and  sterno- 
thyroid muscles.  If  these  cannot  be  drawn  aside  they  should  be  divided  near  their 
upper  ends  in  the  same  manner  as  already  advised  in  the  case  of  division  of  the 
sternomastoid  in  removing  tuberculous  nodes.  The  sternomastoid  muscle  will  have 
to  be  drawn  outward. 

The  internal  jugular  vein  often  overlaps  the  common  carotid  artery,  reaching 
sometimes  even  to  its  inner  side,  so  that  the  position  of  the  artery  is  not  a  sure  guide 
to  the  location  of  this  vein. 

When  a  goitre  dips  behind  the  sternum  the  presence  of  the  left  innominate 
vein  should  not  be  forgotten. 

THE  PARATHYROID  BODIES. 

The  parathyroid  bodies  are  usually  four  in  number,  but  rarely  there  may  be  five 
or  six.  They  are  6  to  7  mm.  long,  3  to  4  mm.  broad,  and  1.5  to  2  mm.  thick.  The 
most  constant  site  of  the  superior  parathyroid  is  at  the  middle  or  junction  of  the  upper 
and  middle  thirds  of  the  posterior  edge  of  the  thyroid  gland  opposite  the  cricoid  carti- 
lage. The  lower  parathyroid  is  near  the  lower  pole,  but  may  be  below  it.  They  are 
small  brownish  bodies  in  the  meshes  of  the  loose  connective  tissue  forming  the  outer 
capsule  of  the  gland.     Often  they  are  quite  distinct  from  the  gland,  but  sometimes 


i66 


APPLIED    ANATOMY. 


they  lie  in  a  cleft  in  the  gland  and  thereby  escape  recognition.  They  possess  a  separate" 
capsule.  They  are  supplied  by  a  separate  artery,  the  parathyroid,  a  branch  of  the 
inferior  thyroid.  This  latter  usually  gives  off  two  parathyroid  arteries,  one  to  each 
body.  Ginsburg  {Univ.  Pe?ma.  Med.  Bulletin,  Jan.,  1908)  has  demonstrated  a  free 
anastomosis  with  the  vessels  of  the  opposite  side.  In  many  cases  it  is  practically 
impossible  to  avoid  wounding  or  removing  the  parathyroids  in  operations — Halsted 
has  suggested  three  means  of  avoiding  their  removal,  viz. :  ( r )  slice  of?  and  leave  the 
piece  of  thyroid  gland  supposed  to  contain  the  parathyroids;  (2)  ligate  the  superior 


Inferior  constrictor 
Superior  thyroid  artery 

Cricothyroid  muscle 
Superior  parathyroid 
Inferior  thyroid  artery 

Thyroid  gland 

Inferior  parathyroid 

CEsophagus 

Recurrent  laryngeal  nerve 

Trachea 


Fig.  185. — Showing  the  parathyroid  bodies. 

and  inferior  thyroids,  and  a  week  or  two  later  perform  a  subcapsular  enucleation  of  the 
thyroid;  (3)  search  for  each  parathyroid  by  following  out  the  ramifications  of  the 
inferior  thyroid  artery — this  is  the  best  method  of  finding  them  in  post-mortem 
examinations. 

CESOPHAGUS— CERVICAL  PORTION. 

The  oesophagus  runs  from  the  level  of  the  cricoid  cartilage  to  the  stomach. 
The  cricoid  is  opposite  the  sixth  cervical  vertebra  and  the  cardiac  or  oesophageal  end 
of  the  stomach  is  opposite  the  lower  border  of  the  tenth  thoracic  vertebra.  It  is  in  the 
median  line  above,  then  curves  slightly  to  the  left  until  the  root  of  the  neck  is 
reached,  when  it  returns  to  the  median  line  opposite  the  fifth  thoracic  vertebra. 

It  is  in  front  of  the  spine  and  the  prevertebral  fascia.  The  layer  of  fascia  between 
its  anterior  surface  and  the  trachea  is  extremely  thin.  On  each  side  are  the  common 
carotid  arteries  and  the  sheath  of  the  vessels.  The  right  recurrent  laryngeal  nerve 
winds  around  the  commencement  of  the  first  portion  of  the  subclavian,  and  passes 


THE    NECK. 


167 


inward  and  upward  behind  the  common  carotid  artery  to  reach  the  groove  between 
the  trachea  and  oesophagus  in  which  it  ascends  to  the  larynx. 

On  the  left  side  the  recurrent  laryngeal  nerve  winds  around  the  arch  of  the  aorta 
and  ascends  in  the  groove  on  the  left  side  between  the  trachea  and  oesophagus.  The 
left  carotid  artery  is  closer  to  the  oesophagus  than  the  right.  The  narrowest  point  of 
the  lumen  is  at  the  cricoid  cartilage.  Its  next  narrow  point  is  where  it  crosses  the  aorta 
and  left  bronchus.  This  is  opposite  the  upper  part  of  the  second  piece  of  the  sternum 
or  the  upper  border  of  the  fifth  thoracic  vertebra.  The  third  narrow  portion  is  the 
cardiac  opening  into  the  stomach.  Mouton  (Tillaux,  "Anat.  Topograph.,"  p.  418) 
gives  the  diameter  of  the  oesophagus  at  each  of  these  three  points  as  14  mm. 

Foreign  Bodies. — Foreign  bodies  if  they  pass  the  cricoid  cartilage  are  most 
liable  to  stop  at  the  aorta  and  the  left  bronchus.     This  is  opposite  the  angle  of  Ludwig 


Left  common 
carotid  artery 

Vagus  nerve 

Internal  jugular 
vein' 

Inferior  thyroid 
artery 

Vertebral  artery 

Thoracic  duct 

Phrenic  nerve 
Recurrent  laryn- 
geal nerve 
Subclavian 
artery  ' 
Bronchial  artery 

Pulmonary  artery 

Left  vagus  nerve7 


Internal  jugular 
vein 

Vagus  nerve 
Common  carotid 
artery 

Inf.  thyroid  artery 
■Vertebral  artery 
Trachea 

Recurrent  laryn- 
geal nerve 
CEsophagus 
Vagus  nerve 
Phrenic  nerve 
Vena  azygos 
major 
■Right  bronchus 

Right  pulmonary 
artery 

Pulmonary  vein 


Fig.  186. — Relations  of  the  cervical  portion  of  the  oesophagus,  viewed  posteriorly. 

and  the  second  rib,  so  that  the  foreign  body  is  either  at  the  root  of  the  neck  or  just 
below  the  top  of  the  sternum.  If  it  passes  the  two  upper  constrictions  it  will  prob- 
ably pass  the  third,  because  the  cardiac  constriction  is  caused  by  the  diaphragm,  which 
relaxes  and  allows  the  body  to  enter  the  stomach. 

CEsophagotomy. — In  operating,  an  incision  is  made  along  the  anterior  border 
of  the  left  sternomastoid  muscle  from  the  sternoclavicular  joint  upward.  The  anterior 
jugular  vein  will  be  cut.  After  opening  the  deep  fascia  the  sternomastoid  is  to  be 
pulled  outward.  The  omohyoid  is  to  be  drawn  up  and  out  and  also  the  lower  por- 
tion of  the  sternohyoid  and  perhaps  the  sternothyroid. 

The  middle  thyroid  and  perhaps  an  accessory  thyroid  vein  are  divided  and  the 
thyroid  gland  and  trachea  drawn  inward.  The  trachea  is  to  be  identified  by  the 
sense  of  touch.  The  inferior  thyroid  artery  is  behind  the  sheath  of  the  vessels  and  is 
so  high  that  it  is  not  likely  to  be  injured.  The  recurrent  laryngeal  nerve  must  be 
looked  for  between  the  oesophagus  and  trachea,  and  avoided.  In  going  deep  down 
care  must  be  taken  not  to  injure  the  innominate  vein,  which  comes  well  up  towards  the 
top  of  the  sternum. 


i68 


APPLIED    ANATOMY. 


CUT  THROAT. 

The  most  frequent  site  of  the  incision  in  cases  of  cut  throat  is  between  the  hyoid ' 
bone  and  thyroid  cartilage.  If  above  the  hyoid  bone,  the  incision  will  divide  the 
mylohyoid,  geniohyoid,  geniohyoglossus,  and  hyoglossus  muscles,  and  perhaps  the 
digastric  and  stylohyoid.  If  it  goes  far  back  it  may  wound  the  submaxillary  gland 
or  duct,  the  facial  or  lingual  arteries  and  veins,  and  the  hypoglossal  nerve.  The 
commencement  of  the  anterior  jugular  will  certainly  be  divided  and  the  external 
jugular  may  also  be  wounded.  The  cut  passes  through  the  base  of  the  tongue  and  the 
upper  portion  of  the  epiglottis.  The  tip  of  the  epiglottis  is  sometimes  entirely  cut  of?. 
If  in  the  thyrohyoid  space,  the  incision  passes  a  short  distance  above  the  vocal  cords. 
The  sternohyoid,  omohyoid,  and  thyrohyoid  muscles  are  divided.  If  prolonged 
backward  the  pharynx  will  be  opened  and  perhaps  the  arytenoid  cartilages  wounded. 
The  superior  thyroid  artery  is  Hkely  to  be  cut.  This  is  the  vessel  most  often  divided 
in  suicidal  wounds.  The  carotid  arteries  and  internal  jugular  veins  are  deep  and  far 
back,  lying  under  the  edge  of  the  sternomastoid  muscle,  and  are  rarely  wounded. 


Sternohyoid  muscle 


Sternothyroid  muscle 


Thyroid  gland 


Recurrent  laryn- 
geal nerve 


Omohyoid  muscle 

,  Inferior  thyroid  artery 
Common  carotid  artery 

Sternomastoid  muscle 


(Esophagus 


Exposing  the  resophagus. 


If  these  are  cut,  death  usually  rapidly  ensues  from  hemorrhage.  The  superior 
laryngeal  nerve  may  be  injured  as  it  pierces  the  thyrohyoid  membrane.  This  nerve 
is  sensory  and  its  division  is  followed  by  anaesthesia  of  that  half  of  the  larynx  to 
which  it  is  distributed.  This  favors  the  entrance  of  food  and  liquids  into  the  larynx 
and  so  may  cause  a  fatal  septic  pneumonia.  If  through  the  thyroid  cartilage  the 
incision  may  wound  the  vocal  cords.  They  lie  just  beneath  the  most  prominent 
part  of  the  thyroid  cartilage  and  just  below  its  median  notch.  If  through  the  trachea, 
the  incision  may  wound  the  thyroid  gland,  which  reaches  from  about  the  sixth  ring 
of  the  trachea  to  the  oblique  line  on  the  thyroid  cartilage. 

Bleeding  from  the  wounded  thyroid,  if  the  gland  is  normal  in  size,  is  not  likely 
to  be  excessive.  Below  the  cricoid  cartilage  the  oesophagus  may  be  wounded,  above 
it  the  pharynx  may  be  opened.  The  two  large  sternomastoid  muscles  being  put  on 
the  stretch  tend  to  protect  the  large  vessels  beneath.  Suppuration  not  infrequently 
accompanies  these  wounds  of  the  neck  in  which  the  air  and  food  passages  are  in- 
volved and  may  give  rise  to  collections  of  pus  which  may  travel  between  the  fascias,  as 
previously  described.  In  treatment  it  is  customary  to  cleanse  the  wounds  and  approxi- 
mate the  various  injured  tissues  as  carefully  as  possible,  and  feed  by  a  stomach  tube. 


THE    NECK. 


169 


AFFECTIONS  OF  THE  NECK. 

Cervical  Cysts  and  Fistulae. — The  neck  is  the  seat  of  some  very  peculiar 
cystic  tumors  and  fistulae  which  are  connected  with  developmental  defects.     They 


first  arch 


Fig.  188. — Foetus,  2Sth  day  (after  His).    Showing  branchial  (visceral)  arches  and  clefts  or  furrows. 


are  either  lateral  or  median  in  location.  The  lateral  originate  from  the  visceral 
(branchial)  clefts,  while  the  median  are  connected  with  the  thyroglossal  duct.  The 
visceral  clefts  are  depressions  between  the  visceral  arches.  These  arches,  five  in 
number,  spring  forward  from  each  side  of  the  embryo  to  form  the  neck  region. 
Sometimes  these  arches  are  called  branchial  arches  from  the  fact  of  their  going  to 
form  the  branchiae  or  gills  of  fishes  and 
some  of  the  other  lower  orders  of  animals. 

The  first  visceral  arch  di\'ides  into 
two  parts,  a  maxillary  part  forming  the 
upper  jaw  and  a  mandibular  part  form- 
ing the  lower  jaw.  Defects  in  the  max- 
illary arch  producing  harelip  and  cleft 
palate  have  already  been  described. 
Two  of  the  ear  bones,  the  incus  and 
malleus,  are  also  formed  by  the  mandib- 
ular portion  of  the  first  visceral  arch. 

The  second  visceral  arch  forms  the 
stapes,  the  styloid  process,  the  stylo- 
hyoid ligament,  and  the  lesser  horn  of 
the  hyoid  bone. 

The  third  visceral  arch  becomes  the 
body  and  greater  horn  of  the  hyoid  bone. 

Thefotaih  snid  fifth  visceral  arches 
blend  and  form  the  soft  structures  of  the 
side  of  the  neck. 

The  first  visceral  cleft,  called  the 
hyomandibular  cleft  from  its  being  be- 
tween the  hyoid  bone  and  the  mandible, 
forms  the   middle   ear   and  Eustachian 

tubes  from  its  inner  portion  and  the  external  auditory  meatus  from  its  outer  portion. 
The  membrana  tympani  is  the  remains  of  the  membrane  which  stretched  across  from 
one  arch  to  the  other.  Cervical  fistulae  are  formed  by  the  persistence  of  a  visceral 
cleft.      As  the  first  visceral  cleft  persists  normally  in  the  structures  already  named,  it 


Fig.  189. — Points  of  opening  of  sinuses  originating 
from  the  thyroglossal  duct  and  branchial  clefts.  (Modi- 
fied from  Sutton.) 


170 


APPLIED    ANATOMY. 


in  itself  does  not  form  pathological  fistulae,  but  congenital  fistulae  are  sometimes 
encountered  in  the  external  ear  which  are  the  remains  of  the  clefts  between  the 
tubercles  of  which  the  ear  is  formed. 

Cervical  fistulae  or  sinuses  may  extend  either  completely  through,  from  the 
surface  to  the  pharynx,  or  may  open  internally  or  externally,  or  be  closed  at  both 
ends,  in  which  last  case  the  contents  accumulate  and  form  a  cervical  cyst. 

FistulcE  arising  from  the  second  visceral  cleft  open  externally  opposite  the  thyro- 
hyoid space  in  front  of  the  s'ternomastoid  muscle.  Internally  they  open  into  the 
recess  holding  the  tonsil. 

Fistula  arising  from  the  third  and  fourth  visceral  clefts  open  externally  lower 
down  nearer  the  sternoclavicular  articulation  in  front  of  the  sternomastoid  muscle  and 

internally  in  the  sinus  pyriformis.  The 
persistence  of  the  third  and  fourth 
visceral  clefts  internally  may  produce 
pharyngeal  diverticula,  as  already 
noted  in  discussing  that  region. 

In  attempting  the  cure  of  cysts 
and  fistulae  due  to  persistence  of  the 


Thyroglossal  duct 


Median  cervical, 
pouch  or  cyst 


Fig.  190. — Median  cervical  pouch  or  cyst  arising  from  the 
thyroglossal  duct. — Marshall's  case. 


Fig.  191. — Median  cervical  (thyroglossal) 
cyst. — Author's  case. 


visceral  clefts  it  is  evident  that  as  they  are  lined  with  a  secreting  epithelium  this  must 
be  destroyed  or  removed,  or  a  recurrence  will  take  place.  In  attempting  to  dissect 
them  out  one  must  be  prepared  to  follow  them  through  the  structures  of  the  neck 
to  the  pharynx  inside.    It  is  needless  to  say  this  may  be  a  serious  procedure. 

Hueter  (quoted  by  Sutton)  followed  one  between  the  two  carotid  arteries  into  the 
pharynx.     These  cysts  and  fistulae  may  be  noted  at  birth  or  may  develop  later  in  life. 

Hydrocele  of  the  Neck. — There  are  other  cystic  tumors  of  the  neck  which 
are  congenital,  being  noticed  at  birth,  and  which  grow  to  a  large  size.  They  are 
often  wide-spread,  extending  not  only  between  the  tissues  of  the  neck  below  the 
deep  fascia  but  even  into  the  axilla.  Their  walls  are  thin,  consisting  sometimes  only 
of  a  layer  of  lining  epithelium  and  the  surrounding  tissues.  On  this  account  it  is 
impossible  to  dissect  them  out.  The  use  of  injections  and  setons  has  been  aban- 
doned as  too  dangerous.  They  rarely  require  treatment,  as  they  tend  to  disappear 
spontaneously.  Mr.  J.  Bland  Sutton  ascribes  their  origin  first  to  congenitally  dilated 
lymph-spaces;  second  2iS>  resembling  the  cervical  air-sacs  that  exist  in  the  howling 
monkeys;  and  third  that  possibly  some  of  them  may  be  related  to  a  persistence  of 
some  portion  of  a  branchial  cleft. 

Median  cervical  fistulae  and  cysts  originate  in  connection  with  the  thyro- 
glossal duct.     This,  in  the  embryo,  leads  from  the  foramen  caecum  at  the  root  of  the 


THE   THORAX.  171 

tongue  through  to  the  posterior  surface  of  the  hyoid  bone  and  thence  downward  and 
forward  to  the  isthmus  of  the  thyroid  gland.  It  begins  to  atrophy  in  the  fifth  week 
and  is  obHterated  by  the  eighth.  According  to  Sutton  these  cysts  are  never  congen- 
ital but  occur  soon  after  birth  or  as  late  as  the  fourteenth  year.  They  appear  as 
rounded,  cystic  tumors  just  below  the  hyoid  bone  or  over  the  thyroid  cartilage.  They 
either  inflame  and  break  of  their  own  accord,  discharging  externally,  or  are  opened  by 
the  surgeon  and,  contrary  to  what  is  the  case  in  hydroceles  of  the  neck,  never  tend  to 
disappear,  but  a  sinus  remains.  At  times  it  almost  heals,  then  the  contents  accumulate 
and  a  cyst  forms,  this  again  breaks  and  a  sinus  results  as  before.  In  attempting  a  cure 
by  operation  the  sinus  should  be  followed  up  behind  the  hyoid  bone.  In  one  case  after 
two  failures  of  attempted  excision  a  cure  was  obtained  by  destroying  the  tract  by 
introducing  a  small  gahanocautery  point.  Unless  every  portion  of  the  lining  mem- 
brane be  completely  destroyed  the  cells  will  go  on  secreting  and  reproduce,  in  a 
short  time,  the  original  condition.  Failure  to  cure  these  sinuses  and  cysts  by  excision 
often  occurs,  notwithstanding  the  exercise  of  the  greatest  care. 

The  lower  portion  of  the  thyroglossal  duct  may  persist  in  the  form  of  the  pyramid 
or  third  lobe  of  the  thyroid  gland,  which  arises  from  the  isthmus  or  from  the  left  side 
and  ascends  as  far  as  the  hyoid  bone,  to  which  it  is  attached. 

THE  THORAX. 

The  thorax  or  chest  is  that  portion  of  the  trunk  which  lies  between  the  neck 
and  the  abdomen.  It  is  composed  of  a  bony  framework  reinforced  by  soft  parts, 
and  contains  the  main  organs  of  circulation  and  respiration.  The  oesophagus,  an 
organ  of  the  digestive  tract,  simply  passes  through  it  to  the  regions  below.  The 
chest-walls  as  well  as  the  parts  contained  within  them  are  affected  by  wounds  and 
disease,  especially  the  heart  and  its  associated  great  vessels,  and  the  lungs  and 
pleurae.  These  organs  are  essential  to  life,  like  the  brain  and  spinal  cord,  and  like 
them,  are  encased  in  a  bony  framework.  It  is  an  example  of  bones  performing  a 
protecting  function  in  addition  to  a  supporting  one. 

The  functions  of  the  heart  and  lungs  are  influenced  by  constitutional  diseases  in 
addition  to  their  own  local  affections,  hence  they  serve  as  guides  to  the  general  bodily 
condition,  and  the  condition  of  the  respiration  and  circulation  is  continually  being  exam- 
ined for  the  purposes  of  diagnosis,  prognosis,  and  treatment,  even  when  the  heart  and 
lungs  themselves  are  not  involved.  To  make  these  examinations  intelligently,  neces- 
sitates a  knowledge  of  the  organs  themselves  and  their  relation  to  one  another  and  the 
surrounding  parts.    This  is  essential  for  the  physician  even  more  than  the  surgeon. 

The  chest- walls  are  composed  of  a  bony  framework  joined  and  bound  together 
and  covered  by  soft  parts. 

The  bones  of  the  chest  consist  of  the  stermim,  ribs,  and  thoracic  vertebrce.  The 
clavicle  and  scapula  compose  the  shoulder-girdle  and  belong  to  the  upper  extremity. 
The  human  skeleton  is  divided  into  an  axial  portion  and  an  appendicular  portion.  The 
axial  portion  embraces  the  skull,  the  vertebral  column,  including  the  sacrum  and 
coccyx,  the  hyoid  bone,  the  sternum,  and  the  ribs.  The  appendicular  portion  con- 
sists of  the  shoulder-girdles  and  upper  extremities  and  the  pelvic  girdles  and  lower 
extremities. 

The  bony  chest  is  subject  to  disease  and  injury  as  well  as  to  defects  in  develop- 
ment, and  to  deformities  due  to  these  causes. 

Shape  of  the  Chest. — The  chest  is  conical  in  shape,  being  small  above  and 
large  below.  In  transverse  section  it  is  kidney-shaped,  the  hilus  of  the  kidney  being 
represented  by  the  vertebrae.  In  the  foetus  the  anteroposterior  diameter  is  greater 
than  the  transverse,  thus  resembling  the  thorax  in  the  lower  animals.  After  "birth 
and  in  infancy  the  two  diameters  are  nearly  equal,  hence  we  have  the  rounded  chest 
of  the  child.  As  growth  and  development  progress  the  transverse  diameter  increases 
more  than  the  anteroposterior,  so  that  at  about  the  second  year  the  chest  has  become 
oval  and  in  adults  the  transverse  diameter  is  one-fourth  greater  than  is  the  antero- 
posterior. 

Variations  in  the  shape  of  the  chest  are  mainly  the  result  of  disease.  In  child- 
hood, rachitic  disease  (rickets)  produces  a  lateral  flattening  and  a  projection  of  the 


172 


APPLIED    ANATOMY. 


sternum.  If  the  sternum  projects  markedly  it  constitutes  what  is  known  as  pigeon 
breast,  the  chest  in  such  a  condition  being-  longer  from  before  backward  than  from  side 
to  side.      In  this  disease  also  there  may  be  a  depression  on  each  side  of  the  sternum, 


Clavicular  articulation 
Manubrium 


Angulus  stemi  or 
angle  of  Ludwig 


Body  or  gladiolus 


•Xiphostemal  articulation 

Xiphoid  or  ensiform 
cartilage 


\,% 


Fig.  192. — The  bony  thorax. 

the  back  is  rounded  owing  to  the  bending  of  the  vertebral  column,  and  the  points  of 
junction  of  the  ribs  and  cartilages  are  enlarged,  this  latter  constituting  what  is  known 

as  beading  of  the  ribs.     These  beads  are 

felt  as  rounded  enlargements  at  the  sternal 

extremities   of    the   ribs   and  form    a    line 

parallel  to  the  sternum  above  and  sloping 

outward   below.     This   line   of  beads  has 

been  called  the  ''  rachitic  rosary.''     From 

the  level  of  the  ensiform  cartilage  a  groove 

passes   out    toward    the    sides ;    this   has 

been   called    ''  Harrison' s  groove"    (see 

Fig.    193).      Sometimes  the  lower  end  of 

^j|L,  •^  &-^^^"^^^^^^B        ^^^^  sternum  is  pressed  inward,  forming  a 

^BK^BT  ^^^^K        deep  funnel-shaped  depression  constituting 

^^^If  ^^^1        the  deformity  known  as  "" fimnel  chest" 

or  the  ''  Trichterbrust"  of  the  Germans. 
This  condition  of  the  chest,  with  the 
exception  of  the  beading,  is  also  produced 
in  children  by  obstruction  to  the  breathing 
from  enlargement  of  the  tonsils,  from  the 
presence  of  adenoid  growths  in  the  pharynx, 
and  from  hypertrophy  of  the  turbinate 
bones,  all  of  which  interfere  particularly 
with  nasal  respiration. 

Diseases  of  the  lungs  and  pleurae  alter 
the  shape  of  the  chest.  In  emphysema  and 
when  distended  by  plural  effusions,  the 
thorax  becomes  more  rounded  in  shape, 
forming  what  is  called  the  ' '  barrel-shaped 
chest."  In  phthisis  the  wasting  of  the  tissues  and  contraction  of  the  lungs  causes  the 
chest  to  collapse.     The  ribs  slope  more  sharply  downward  and  the  chest  becomes 


xH 


Fig 


-Child  showing  Harrison's  groove  opposite 
the  ensiform  cartilage. 


THE   THORAX. 


173 


longer  and  flatter,  the  anteroposterior  diameter  being  diminished.  The  angle  made 
by  the  lower  ribs  as  they  ascend  to  the  sternum  is  called  the  costal  angle ;  this 
becomes  decreased  in  phthisis.     This  form  of  chest  is  known  as  the  '  'phthisical  chest. 


/ 


Fig.  195. — Flat  chest  of  phthisis. 


Fig.  194. — Barrel  chest  of  emphysema. 

When  the  flatness  is  marked  it  is  sometimes  called  the  '  ''flat  chest. ' '  When  the  scapulae 
project  like  wings  it  is  called  ^'alar''  or  ''pterygoid  chest.' ^ 

In  Pott's  disease,  or  caries  of  the  spine,  as  the  kyphosis  develops  the  chest  falls  for- 


PiG.  196. — Kyphosis  from  Pott's  disease,  or  caries 
of  the  lower  thoracic  vertebrse.  The  curvature  is  an 
angular  anteroposterior  one. 


Fig.  197. — Scoliosis,  or  lateral  curvature  of  the  spine. 


ward  and  its  anteroposterior  diameter  is  increased.  The  abdominal  contents  are  crowded 
up  into  the  chest  and  push  the  sternum  and  lower  ribs  forward.  Associated  with  this 
deformity  is  oftentimes  a  lateral  deviation  of  the  parts  above  the  site  of  the  disease. 


174  ^m^  APPLIED   ANATOMY.  ^SKKKB^I^m 

In  scoliosis,  or  lateral  curvature  of  the  spine,  the  distortion  is  uneven,  being  a 
compression  of  the  thorax  from  above  downward  and  a  twisting  around  a  vertical 
axis.  The  deformity  is  frequently  so  severe  as  to  cause  the  lower  ribs  to  rest  on  the 
iliac  crests.  It  is  in  order  to  detect  these  diseases  in  their  early  stages  that  a  know- 
ledge of  the  shape  of  the  normal  chest  is  so  essential. 

THE   STERNUM.  "I 

The  sternum  consists  of  three  pieces:  the  niamibrium  ox  presternum,  gladiolus 
or  nicsosteruutn,  and  xiphoid  cartilage  or  metaster^ium.  It  is  developed  in  two 
lateral  halves.  Should  these  fail  to  unite  an  opening  is  left  in  the  bone  through  which 
the  pulsations  of  the  heart  have  been  seen  and  felt.  The  junction  of  the  first  and 
second  pieces  of  the  sternum  is  opposite  the  second  rib.  The  se\enth  is  the  last  rib 
to  articulate  with  the  sternum  directly. 

The  first  and  second  pieces  of  the  sternum  are  connected  by  a  joint  which  per- 
sists to  advanced  age.  The  projection  caused  by  this  joint  is  called  the  angulus  sterni 
or  angle  of  Ludwig.  Fractures  pass  either  through  this  joint,  opposite  the  second 
rib,  or  through  the  bone  just  below  it.  They  are  produced  by  both  direct  and 
indirect  force.  Usually  the  upper  fragment  is  beneath  the  lower  one.  It  is  however 
more  true  to  state  that  the  lower  fragment  is  displaced  anteriorly.  Any  marked  pos- 
terior displacement  of  the  upper  fragment  would  tend  to  press  on  the  trachea  and  in- 
terfere with  breathing;  the  trachea  bifurcates  opposite  the  joint.  As  the  pleurae  and 
lungs  of  the  two  sides  almost  or  quite  touch  behind  the  second  piece  of  the  sternum, 
they  may  be  wounded  and  emphysema  may  occur.  The  heart  also  maybe  wounded. 
Suppuration  has  followed  these  injuries,  in  which  case  it  will  be  necessary  to  trephine 
the  sternum  to  give  exit  to  the  pus.  The  necessity  of  avoiding  wounding  of  the 
pleurae  in  such  a  procedure  is  evident,  as  it  would  be  followed  by  collapse  of  the  lung 
and  empyema. 

THE   RIBS   AND   COSTAL    CARTILAGES. 

The  ribs  are  frequently  fractured,  sometimes  they  become  affected  with  caries, 
and  in  operating  the  chest  is  frequently  opened  between  them  or  portions  of  them 
are  excised.  They  are  both  elastic  and  movable,  and  difficult  to  break;  hence  frac- 
ture is  almost  always  due  to  direct  violence,  and  this  violence  may  be  so  great  as 
sometimes  to  cause  death.  Normally  there  are  twelve  ribs  on  each  side,  but  some- 
times there  is  an  extra  cervical  or  lumbar  rib.  These  are  both  rare,  the  latter  the 
more  so. 

The  seven  upper  ribs  are  called  true  ribs  because  they  articulate  with  the  sternum. 
The  remaining  five  are  called  y«/j'^  ribs,  the  eleventh  and  twelfth  hitxw^  floating  ribs. 
The  eighth,  ninth,  and  tenth  ribs  each  articulate  by  their  cartilages  with  the  rib  above. 
The  tenth  forms  the  lower  margin  of  the  thorax.  The  eleventh  and  twelfth  ribs  are 
attached  only  by  their  posterior  extremities,  their  anterior  portion  being  imbedded  in 
the  soft  parts;  hence  they  are  called  floating  ribs.  The  ribs  slope  downward  and 
forward.  This  obliquity  increases  until  the  ninth  rib,  after  which  it  decreases.  The 
first  rib  in  front  corresponds  to  the  fourth  behind,  the  second,  third,  fourth,  fifth, 
sixth,  and  seventh  in  front  correspond  each  to  the  fourth  rib  lower  behind.  The  first 
rib  is  the  nearest  horizontal  in  regard  to  its  surface  and,  being  well  protected  by  the 
clavicle,  is  rarely  broken.  The  intercostal  spaces  are  broader  in  front  than  behind 
and  broader  above  than  below.     The  third  is  the  largest. 

The  groove  on  the  lower  surface  of  the  ribs  holds  the  intercostal  artery,  but  only 
as  far  back  as  the  angle,  from  which  point  it  occupies  the  middle  of  the  space. 

The  extent  of  the  intercostal  spaces  is  considerably  influenced  by  position — flexion 
of  the  body  brings  the  ribs  together,  extension  and  bending  to  the  opposite  side 
separates  them.  This  point  is  of  importance  in  reference  to  the  operations  of  para- 
centesis and  empyema. 

The  first  costal  cartilage  unites  directly  with  the  sternum,  there  being  no  joint 
present.  The  second  and  sometimes  the  third  cartilage  is  joined  to  the  sternum  by 
a  ligament  with  a  synovial  joint  above  and  below  it.     The  other  costal  cartilages  are 


THE   THORAX. 


175 


united  by  a  joint  with  a  single  cavity.      These  joints  may  be  the  seat  of  metastatic 
abscesses  in  pyaemic  infections. 

Cervical  ribs  spring  from  the  body  and  transverse  process  of  the  seventh 
cervical  vertebra.  They  may  be  long  enough  to  reach  to  the  sternum,  but  usually 
are  much  shorter.  One  case  of  this  affection  was  seen  by  the  writer  in  a  man 
twenty-seven  years  of  age.  There  was  an  abnormal  fulness  above  the  scapula 
posteriorly,  and  above  the  clavicle  anteriorly,  just  to  the  inner  side  of  the  external 
jugular  vein,  a  distinct  bony  process  could  be  felt.  This  did  not  move  with  the 
scapula  or  clavicle  but  did  move  somewhat  with  respiration.  A  skiagraph  showed 
it  to  be  attached  to  the    spine.     The   patient   was    seen    again   live    years  later, 


Fig.  198. — A  cervical  rib  attached  to  the  right  side  of  the  seventh  cervical  vertebra. 


when  the  same  condition  of  affairs  existed,  with  the  exception  that  movement  on 
respiration  was  not  so  marked.  A  knowledge  of  the  possible  presence  of  a  cervical 
rib  is  important  in  diagnosis,  otherwise  it  may  be  thought  to  be  a  bony  or  malignant 
new  growth  and  treatment  advised  accordingly.  The  subclavian  artery  may  pass 
over  the  cervical  rib  above  and  may  have  its  circulation  seriously  interfered  with. 

Fracture  of  the  Ribs. — The  ribs  are  almost  always  broken  by  direct  violence; 
fractures  from  indirect  force,  as  from  coughing,  sneezing,  and  other  forms  of  muscular 
exertion,  are  rare.  Fracture  from  compression  of  the  chest  is  also  rare.  The  site  of 
the  fracture  is  most  frequentiy  on  the  anterior  portion  of  the  chest  and  not  the  sides 


Fig.  199. — Fractured  ribs;  fusion  of  callus. 


or  back.  The  fourth,  fifth,  sixth,  and  seventh  ribs  are  most  often  broken.  The  first 
rib  is  well  protected  from  direct  blows  by  the  clavicle.  Lane,  however,  has  shown 
that  it  can  be  broken  by  pressure  of  the  clavicle  when  the  shoulder  is  depressed. 
The  eleventh  and  twelfth,  being  floating  ribs,  are  rarely  broken.  The  twelfth  rib  is 
the  least  frequently  so.  In  one  case  we  saw  the  eighth,  ninth,  tenth,  eleventh,  and 
twelfth  all  broken  by  the  passage  of  a  wheel.  The  soft  parts  attached  to  the  frag- 
ments prevent  much  displacement,  but  there  is  always  some,  due  to  the  respiratory 
movements.  Hence  callus  is  always  present  and  it  may  be  so  abundant  as  to  join 
adjacent  ribs  (see  Fig.  199).  As  already  stated,  death  frequently  follows  fracture  of 
the  ribs  and  is  due  to  wounding  of  the  chest  contents.  Rarely  the  intercostal  arteries 
may  be  wounded  and  produce  haemothorax.     Wounding  of  the  lung  is  frequent. 


176  T^S^B^       APPLIED    ANATOMY.  IMBJJffjiy:  'JJUfJ 

Emphysema  of  the  surface  of  the  body  may  ensue,  but  is  not  dangerous.  Pneumo- 
thorax, which  may  be  accompanied  by  infiltration  of  air  into  the  lung  tissue,  is  more 
dangerous,  favoring  collapse  of  the  lung.  The  object  of  treatment  is  to  keep  the 
chest-walls  from  moving.  This  is  accomplished  by  strapping  the  chest  with  adhesive 
plaster,  which  is  usually  laid  on  almost  in  the  direction  of  the  ribs ;  but  as  the  chest 
moves  with  respiration,  the  ribs  rising,  and  as  they  slope  downward  and  forward,  I 
have  preferred  to  lay  the  straps  on  from  in  front  downward  and  backward,  this  tends 
to  prevent  the  ribs  from  rising  in  inspiration. 

THE  THORACIC   VERTEBRA.  m 

The  thoracic  or  dorsal  vertebrae  are  twelve  in  number  and  are  so  articulat^i 
with  one  another  as  to  form  a  single,  regular  curve  with  its  concavity  forwards  and 
convexity  backward.  Any  sudden  change  in  the  direction  of  the  curve  is  an  evidence 
of  disease;  this  is  seen  in  the  angular  curvature  of  Pott's  disease  or  caries  of  the 
spine.  The  ribs  are  connected  with  the  vertebrae  by  the  articulation  of  the  head  of 
the  rib  with  the  body  of  the  vertebra,  and  the  tubercle  of  the  rib  with  the  transverse 
process.  The  transverse  process  is  connected  with  the  body  by  the  pedicle  and  with 
the  spinous  process  by  the  lamina.  The  spinal  cord  is  exposed  in  operations  by 
removal  of  the  spinous  process  and  laminae,  hence  the  name  laminectomy. 

The  spinous  processes  are  the  guides  which  indicate  the  position  and  condition 
of  the  vertebrae.  Their  tips  are  not  covered  by  muscles  but  lie  close  beneath  the 
skin  and  are  readily  felt  and  any  abnormality  detected.  In  the  normal  body  the 
grooves  on  each  side  of  the  spinous  processes  are  filled  up  with  muscle,  but  in  certain 
diseases,  as  in  infantile  paralysis  and  lateral  curvature,  they  become  atrophied  and 
the  spine  becomes  twisted,  hence  on  the  convex  side  of  the  abnormal  lateral  curve, 
to  the  outer  side  of  the  spines,  the  projection  formed  by  the  transverse  processes  and 
tubercles  of  the  ribs  can  be  both  seen  and  felt. 

The  external  curve  formed  by  the  tips  of  the  spinous  processes  of  the  thoracic 
region  in  the  normal  person  is  not  so  great  as  is  the  curve  formed  by  the  anterior 
portion  of  the  bodies  of  the  thoracic  vertebrae.  This  is  because  the  spinous 
processes  at  the  upper  and  lower  portions  of  the  chest  project  out  almost  at  right 
angles  to  the  long  axis  of  the  body,  while  those  of  the  middle  portion  slope  down- 
ward. Hence  the  tips  of  the  spinous  processes  of  the  seventh  cervical,  first  dorsal, 
and  twelfth  dorsal  vertebrae  are  opposite  the  bodies  of  the  same  vertebrae,  while  the 
others  are  opposite  the  bodies  of  the  vertebrae  next  below.  (The  spine  will  be 
considered  more  at  length  in  the  section  devoted  to  the  Back. ) 

SOFT   PARTS. 

The  bony  thorax  is  lined  by  the  pleurae,  the  ribs  are  united  to  each  other  by 
the  intercostal  muscles,  and  over  all  are  muscles,  superficial  fascia,  and  skin.  In 
addition,  in  front  are  the  mammary  glands  and  behind  are  the  scapulae. 

The  Intercostal  Muscles  and  Arteries. 

The  intercostal  spaces  are  occupied  by  the  two  intercostal  muscles,  with  a  fascia 
above  them,  one  below,  and  one  between  them. 

The  external  intercostal  muscles  run  downward  and  forward.  They  begin  at 
the  tubercles  of  the  ribs  posteriorly  and  end  at  the  costal  cartilages  anteriorly. 
They  are  continued  forward  to  the  sternum  by  the  anterior  intercostal  membrane, 
formed  by  the  fusing  of  the  outer  and  middle  intercostal  fascias.  The  internal 
intercostal  muscles  go  downward  and  backward.  They  begin  at  the  sternum  and 
end  at  the  angles  of  the  ribs.  They  are  continued  to  the  spine  by  the  posterior 
intercostal  membrane,  formed  by  the  fusing  of  the  middle  and  internal  intercostal 
fascias.  The  intercostal  arteries  come  from  both  anteriorly  and  posteriorly.  The 
anterior  intercostals  come  from  the  internal  mammary  for  the  upper  five  or  six 
spaces  and  from  the  musculophrenic  artery  for  the  remainder.  They  arise  either 
as  a  single  trunk  or  as  separate  superior  and  inferior  branches.  At  first  they  are 
between  the  pleura  and  internal  intercostal  muscle,   but  they  soon  perforate  that 


THE   THORAX. 


177 


muscle  and  run  between  it  and  the  external  intercostal,  the  superior  branch  running 
along  the  lower  edge  of  the  rib  and  the  inferior  branch  running  along  the  upper 
edge  of  the  rib  below.  The  aortic  or  posterior  intercostal  arises  as  a  single  trunk 
which  passes  between  the  external  intercostal  muscle  and  the  pleura.  Arriving  op- 
posite the  angle  of  the  ribs  it  divides  into  superior  and  inferior  branches  which 
unite  with  those  from  the  internal  mammary  {arteria  inamviaria  interna). 

From  the  vertebrae  out  to  the  angle  of  the  ribs  the  intercostal  artery  lies  about 
midway  between  the  ribs,  hence  it  is  liable  to  be  wounded  in  paracentesis  if  the 
puncture  is  made  too  far  back.  It  is  for  this  reason  that  operations  for  draining  the 
pleurae  are  performed  anterior  to  the  costal  angles.  The  superior  intercostal 
branches  are  larger  than  the  inferior  ones.  They  run  under  the  lower  edge  of  the 
rib  above  the  space  and  are  therefore  protected  from  injury,  particularly  stab-wounds. 

In  opening  the  chest  for  empyema  it  is  best  to  go  about  midway  in  the  intercosal 
space  and  not  too  close  to  the  lower  edge  of  the  rib  on  account  of  the  liability  of  wound- 
ing the  superior  intercostal.  The  inferior  branch  is  usually  quite  small  and  causes 
no  serious  hemorrhage.     Intercostal  bleeding  may  cause  a  hsemothorax  if  the  wound  is 


Anterior  perfor- 
ating arteries 


Thoracic  aorta 

Posterior  intercostal  arteries 


Anterior  intercos- 
tal arteries 


Internal  mammary  arteries 

Fig.  200. — Course  and  distribution  of  the  intercostal  arteries. 

small.  It  may  be  controlled,  if  the  vessel  is  cut  in  performing  the  operation  of 
paracentesis  for  empyema,  by  clamping  with  haemostatic  forceps.  If  these  are 
allowed  to  remain  on  a  few  minutes  the  bleeding  often  does  not  recur  on  their 
removal.  If  desired  a  ligature  can  be  applied.  If  it  is  undesirable  to  rely  on  the 
clamp  or  ligature  then  the  wound  may  be  hrmly  packed  with  gauze  or  a  piece  of  gauze 
may  be  depressed  through  the  wound  into  the  pleural  cavity  and  then  stuffed  with 
more  gauze,  after  which  the  tampon  so  formed  is  pulled  firmly  outward  against  the 
bleeding:  tissues. 


MUSCLES. 

Covering  the  chest  anteriorly  are  the  pedoralis  major  and  pedoralis  minor 
Tnusclcs.  The  serrattis  anterior  {magnns)  winds  around  its  side  and  posteriorly,  above 
is  the  trapezius  and  below  the  latissinuis  dorsi.  Beneath  them  are  the  erector  spitice 
(^sacro spinalis)  miisdes  on  each  side  of  the  spinous  processes. 

The  pectoralis  major  muscle  arises  from  the  sternal  half  of  the  clavicle,  from 
the  sternum  and  costal  cartilages  as  low  as  the  sixth  or  seventh  rib,  and  from  the 

\7 


178 


APPLIED    ANATOMY. 


aponeurosis  of  the  external  oblique  muscle  and  sheath  of  the  rectus  muscle.  It 
inserts  into  the  outer  lip  of  the  bicipital  groove.  It  is  to  be  noted  in  regard  to  this 
muscle  that  it  is  attached  only  to  the  inner  half  of  the  clavicle  and  that  the  clavicular 


Acromial  branch 

Humeral  branch     \ 

Cephalic  vein    \     \ 

Coracoid  process 

Deltoid 

Clavi pectoral  fascia 


Costocoracold 
membrane 


Superior 
'thoracic  vessels 
and  nerves 


\  Thoracic  branch 

Acromial  thoracic  artery 

Pectoralis  major  Pectoralis  minor 

Fig.  20 1. — The  clavipectoral  fascia. 

and  sternal  parts  are  separated  by  a  cleft.     When  removing  it  in  excision  of  the 
breast  for  carcinoma  one  separates  the  muscle  by  passing  through  this   cleft  and 

detaching  the  part  below.      It  forms  the  anterior 
/j  fold  of  the  axilla  and  by  following  this  fold  to  the 

chest- wall  it  leads  to  the  fifth  rib,  as  it  is  at  that 
rib  that  the  muscle  leaves  the  chest-wall. 

The  pectoralis  major  is  covered  by  the  pec- 
toral fascia.  When  in  removal  of  the 
female  breast  for  nonma- 
lignant  growths  the  breast 
is  raised,  the  muscle  be- 
neath is  seen  to  be  covered 
with  a  thin  fascia  continu- 
ous with  the  fascia  of  the 
axilla.  Beneath  the  pec- 
toralis major  is  the  clavi- 
pectoral fascia  continuous 
with  the  costocoracold 
membrane  above  and  the 
axillary  fascia  at  the  sides. 
The  pectoralis 
minor  passes  from  the 
third,  fourth,  and  fifth  ribs 
to  the  coracoid  process.  Its 
origin  is  well  forward  to- 
ward the  anterior  extremi- 
ties of  the  ribs  and,  as  it  is 
not  attached  so  low  on  the 
chest  as  is  the  pectoralis 
major,  it  is  hidden  by  the  latter  and  does  not  aid  in  forming  the  anterior  axillary  fold. 
This  muscle  is  frequently  removed  in  operations  for  carcinoma  of  the  mammary  gland. 


*^, 


Fi 


202. — The  serratus  anterior  muscle  arising 
nine  upper  ribs. 


by  ten  digitations  from  the 


THE   THORAX. 


179 


The  serratus  anterior  (magnus)  muscle  (Fig.  202)  passes  from  the  side  of 
the  chest  to  the  vertebral  or  posterior  border  of  the  scapula,  arising  by  nine  or  ten 
digitations  from  the  eight  or  nine  upper  ribs,  the  second  having  two.  The  slip  arising 
from  the  sixth  rib  is  the  one  most  prominently  seen  on  raising  the  arm  away  from 
the  side,  it  passes  the  farthest  forward.  The  slips  into  the  fifth,  seventh,  and  eighth 
ribs  may  also  be  seen.      This  muscle  passes  across  the  axilla  from  in  front  backward, 


Stemomastoid 

Splenius 

Levator  (anguli)  scapulae 

Scalenus  medius 


Infraspinatii 


Latissimus  dorsi 


External  obliqui 


Internal  oblique' 


Petit's  triangl 


Fig.  203. — Muscles  of  the  back. 


lying  on  the  chest-wall, 
fifth,   sixth,    and   seventh 
respiratory  nerve  of  Bell. 


It  is  supplied  by  the  posterior  thoracic  nerve  from  the 
cervicals.      This  nerve   is  also   called   the   long  external 
The  interrial  'respiratory  nerve  is  the  phrenic,  which  comes 
from  the  third,  fourth,  and  fifth  cervical  nerves.     One  of  the  main  functions  of  this 
muscle  is  to  keep  the  scapula  applied  to  the  chest  and  to  aid  in  rotating  it  in  elevation 


i8o  APPLIED    x\X ATOMY. 

of  the  arm.  When  it  is  paralyzed  the  arm  cannot  be  raised  beyond  a  right  angle 
and  the  scapula  projects,  particularly  at  its  lower  angle  and  posterior  edge.  This 
condition  is  called  ' '  winged  scapula. ' ' 

The  trapezius  muscle  (Fig. 203)  has  the  shape  of  a  triangle,  its  apex  being  out 
on  the  acromion  process  and  its  base  in  the  median  line.  It  arises  posteriorly  from 
the  inner  third  of  the  superior  curved  line  of  the  occiput,  the  occipital  protuberance, 
ligamentum  nuchse,  and  the  spines  of  the  se\'enth  cervical  and  all  the  thoracic  vertebrae. 

It  inserts  into  the  outer  third  of  the  clavicle  and  the  acromion  and  spinous  proc- 
esses of  the  scapula.  It  aids  in  rotating  the  scapula  and  elevating  the  shoulder;  its 
paralysis  is  followed  by  marked  dropping  of  the  shoulder.  It  is  supplied  by  the 
spiiial  accessory  nerve.,  which  is  sometimes  injured  in  operations  for  tumors  involving 
the  posterior  cerxical  triangle. 

The  latissimus  dorsi  muscle  arises  from  the  spinous  processes  of  the  lower  six 
thoracic  vertebrae,  from  the  posterior  layer  of  the  lumbar  fascia,  the  outer  lip  of  the 
posterior  third  of  the  iliac  crest  and  by  digitations  from  the  lower  three  or  four  ribs. 
Sometimes  it  is  attached  to  the  angle  of  the  scapula.  It  unites  with  the  tendon  of  the 
teres  major  muscle  to  be  inserted  into  the  bottom  of  the  bicipital  groove  and  extends 
somewhat  higher  than  the  tendon  of  the  pectoralis  major.  A  bursa,  which  may 
become  inflamed,  sometimes  lies  betw^een  the  muscle  and  the  inferior  angle  of  the 
scapula.     The  latissimus  dorsi  and  teres  major  muscles  form  the  posterior  axillary  fold. 

The  erector  spinae  (sacrospinalis)  muscle  fills  up  the  hollows  on  each  side  of 
the  spinous  processes.  As  the  various  muscular  bundles  are  inserted  into  the  vertebrae 
by  innumerable  small  tendinous  slips,  in  exposing  the  vertebrae  in  performing  lamin- 
ectomy it  is  necessary  to  cut  them  w^ith  a  knife  or  scissors.  One  should  not  attempt 
to  separate  them  by  blunt  dissection.  These  muscles  become  atrophied  in  cases  in 
which  the  spine  becomes  distorted. 

SURFACE  ANATOMY  OF  THE  THORAX. 

On  looking  at  the  chest  one  should  note  whether  or  not  it  appears  normal.  It 
may  show  the  rounded  form  of  emphysema  or  the  flat  form  of  phthisis.  One  side 
may  be  larger  than  the  other,  suggesting  pleural  effusion.  The  intercostal  spaces 
may  be  obliterated,  indicating  the  same  condition.  This  may  be  local  instead  of  over 
the  whole  chest.  Note  whether  Harrison's  groove,  funnel  and  pigeon  breast,  or 
beading  of  the  ribs,  already  described,  are  present.  Aneurism  affecting  the  great 
vessels  may  cause  a  bulging  in  the  upper  anterior  portion,  and  cardiac  disease  may 
produce  marked  changes  in  the  apex  beat.  This  may  be  displaced  to  the  right  side 
by  pleural  effusion. 

The  clavicle  belongs  to  the  shoulder-girdle  and  hence  will  be  described  with  the 
upper  extremity.  Both  it  and  the  sternum  are  subcutaneous  and  can  readily  be  felt 
beneath  the  skin.  The  point  of  junction  of  the  first  and  second  pieces  of  the  sternum 
is  opposite  the  second  costal  cartilage.  It  forms  a  distinct  prominence,  which  is 
readily  felt  and  is  a  most  valuable  landmark.  It  is  called  the  angulns  sterni  or  angle 
of  Louis.  There  is  usually  a  palpable  depression  at  the  junction  of  the  second 
piece  of  the  sternum  and  xiphoid  cartilage. 

The  tip  of  the  xiphoid  or  ensiform  cartilage  can  be  felt  about  4  cm.  below  the 
joint  between  it  and  the  second  piece  of  the  sternum.  The  top  of  the  sternum  is  oppo- 
site the  lower  edge  of  the  second  thoracic  vertebra.  The  angulus  sterni  is  opposite 
the  fifth  vertebra,  the  lower  end  of  the  second  piece  of  the  sternum  is  opposite  the 
tenth,  and  the  tip  of  the  ensiform  cartilage  is  opposite  the  eleventh  thoracic  ver- 
tebra. There  is  usually  comparatively  little  fat  over  the  sternum,  so  that  in  fat  and 
muscular  people  its  level  is  below  that  of  the  chest  on  each  side.  Above  its  upper 
end  is  the  suprasternal  notch  or  depressio7i,  below  its  lower  end  is  the  infrastertial 
depression  or  epigastric  fossa.,  sometimes  called  the  scrobicuhis  cordis. 

With  the  upper  end  of  the  sternum  articulate  the  clavicles.  The  sternoclavicular 
joint  possesses  an  interarticular  cartilage  between  the  clavicle  and  the  sternum.  This 
separates  them  sufficiently  to  allow  the  formation  of  a  distinct  depression,  which  can 
readily  be  felt.  From  the  sternum  to  the  acromion  process  the  clavicle  is  subcuta- 
neous.   Below  the  inner  end  of  the  clavicle  the  first  rib  can  be  often  seen  and  felt.    At 


THE   THORAX. 


i8i 


the  middle  of  the  cla\'icle  it  is  so  deep  from  the  surface  as  not  to  be  accessible  and 
here  the  second  rib  is  the  one  which  shows  just  below  the  clavicle.  In  children  the 
point  of  junction  of  the  cartilages  and  ribs  can  often  be  distinguished;  this  is  par- 
ticularly so  in  cases  of  rachitis. 

The  line  of  junction  between  the  body  of  the  sternum  and  the  ensiform  cartilage 
can  be  distinguished,  and  to  each  side  of  it  is  felt  the  cartilage  of  the  seventh  rib, 
the  last  that  articulates  with  the  sternum.  The  tenth  rib  is  the  lowest  which  is 
attached  anteriorly,  the  eleventh  and  twelfth  being  shorter  and  floating  ribs.  The 
intercostal  spaces  are  wider  anteriorly  than  posteriorly  and  the  third  is  the  widest. 

The  nipple  is  usually  in  the  fourth  interspace  or  on  the  lower  border  of  the  fourth 
rib  and  on  a  line  a  little  to  the  outer  side  of  the  middle  of  the  clavicle.  In  women  its 
position  is  variable,  o  .ving  to  the  breasts  being  pendulous.  The  mammary  gland 
reaches  from  the  third  to  the  seventh  rib.  As  the  pectoralis  major  muscle  does  not 
arise  lower  than  the  sixth  rib  it  is  seen  that  the  mammary  gland  projects  beyond  it,  an 
important  fact  to  be  remembered  in  operations  for  remox-al  of  the  breast. 

Immediately  to  the  outer  side  of  the  upper  edge  of  the  pectoralis  major,  beginning 
at  the  middle  of  the  clavicle  and  below  it,  is  a  hollow.  This  is  the  interval  between 
the  pectoralis  major  and  deltoid  muscles.     At  its  upper  end  it  is  equal  in  width  to  one- 


Suprastemal  notch 
Sternal  end  of  first 
Second  rib 


Angle  of  sternum 
opposite  second  rib 


Xiphostemal 
articulation 


Serrations  of  serratus 
anterior  muscle 

Tip  of  ensiform  process 
Infrastemal  depression 


Space  between  deltoid  and  pectoralis  major 
Outer  end  of  clavicle 
Coracoid  process 

Acromioclavicular  joint 
Acromion  process 


Fig.  204. — Surface  anatomy  of  the  thorax. 


sixth  the  length  of  the  clavicle,  because  the  deltoid  is  attached  only  to  the  outer 
third  of  the  clavicle.  Immediately  beneath  the  edge  of  the  deltoid  muscle  and  about 
2.5  cm.  below  the  clavicle  is  the  coracoid  process.  On  abducting  the  arm  the  scapula 
is  rotated  and  the  serratus  anterior  muscle  is  put  on  the  stretch;  this  makes  its  four 
lower  serrations  visible.  The  serration  attached  to  the  fifth  rib  is  the  highest,  the 
sixth  is  the  most  prominent  and  extends  farthest  forward,  while  below  are  the  last 
two  attached  to  the  seventh  and  eighth  ribs.  The  operation  of  paracentesis,  or  tapping 
for  pleural  effusion,  is  most  often  done  in  the  sixth  interspace  in  the  midaxillary  line. 
This  will  be  about  on  a  level  with  the  nipple.  The  apex  beat  of  the  heart  is  felt  in 
the  fifth  interspace,  about  2. 5  cm.  ( i  in. )  to  the  inner  side  of  the  line  of  the  nipple. 

Running  down  behind  the  costal  cartilages  and  crossing  the  intercostal  spaces 
about  a  centimetre  from  the  edge  of  the  sternum  is  the  internal  mammary  artery. 
When  it  reaches  the  sixth  interspace  it  divides  into  the  superior  epigastric,  which 
goes  downward  in  the  abdominal  walls,  and  the  musculophrenic,  which  passes  to  the 
attachment  of  the  diaphragm  along  the  edge  of  the  chest. 

(  The  relations  of  the  organs  of  the  chest  to  the  surface  will  be  discussed  later. 
The  nervous  supply  to  the  surface  of  the  chest  is  of  interest  mainly  as  indicating  the 
probable  location  of  the  lesion  in  cases  of  fracture  of  the  spine,  and  it  will  be  described 
in  the  section  devoted  to  the  Back.) 


182 


APPLIED    ANATOMY. 


THE  MAMMA  OR  BREAST. 

The  name  mammary  gland  is  often  gi\'en  to  the  breast,  yet  the  latter  is  composed 
not  only  of  glandular  tissue  but  also  of  fibrous  and  fatty  tissue,  with  the  usual  vessels, 
nerves,  and  lymphatics.  In  the  male  the  glandular  portion  is  undeveloped,  the  fat  is 
relatively  scanty,  and  the  breast  as  a  whole  is  insignificant  and  flat.  In  the  virgin 
female  adult  it  is  more  spheroidal.  Above  the  nipple  it  is  flattened  and  below  it  is 
rounded.  Its  general  shape  is  circular  and  it  covers  the  chest-wall  from  the  upper 
border  of  the  third  rib  to  the  sixth  interspace.  Laterally  it  reaches  internally  almost 
to  the  sternum  and  externally  it  overlaps  the  edge  of  the  pectoralis  major.  It  lies 
imbedded  in  the  superficial  fascia.  In  its  development  it  is  simply  a  modified  seba- 
ceous gland.  Beginning  by  a  finger-like  growth  from  the  skin  it  burrows  its  way  into 
the  superficial  fascia.  It  becomes  compound  and  sends  its  branches  in  various  direc- 
tions, especially  does  it  extend  deeper  until  finally  it  pushes  away  most  of  the  fat  and 


^i- 


Areola 


Areolar  glands 


Nipple 


Lobule  of  gland-tissues 


Excretory  duct 


Ampulla 
Lactiferous  duct 
Fig.  205. — The  secreting  structure  of  the  breast.   (Piersol.) 

rests  on  the  fascia  covering  the  pectoralis  major  muscle.  This  is  wh)-  we  find  almost  no 
adipose  tissue  beneath  the  gland  but  mostly  between  the  glandular  structure  and  the 
skin  and  around  its  edges.  The  shape  of  the  virgin  breast  is  due  mainly  to  its  adipose 
tissue  and  not  to  its  glandular  structure.  In  those  who  have  borne  children  the  breasts 
become  enlarged,  lax,  and  pendulous.  After  lactation  is  completed  they  again 
retract  but  rarely  regain  their  former  shape.  During  lactation  the  fatty  portion  of  the 
breast  may  disappear  and  lea\'e  it  apparently  in  a  shriveled  condition,  yet  such  a  breast 
may  be  functionally  quite  active.  Therefore  the  size  of  the  breast  is  no  criterion  of  its 
milk-producing  powers. 

The  secreting  structure,  racemose  in  character,  is  divided  into  ten  to 
sixteen  lobules  each  of  which  has  its  duct.  These  lactiferous  ducts  begin  in  the 
acini  and  end  in  the  nipple.  Beneath  the  nipple  they  are  dilated,  each  forming  a 
sinus  or  ampulla.  While  the  shape  of  the  breast  is  regular  in  its  outline  the 
glandular  tissue  is  not  so.  It  possesses  three  projections  or  cusps.  One  of  these 
projects  inward  nearly  or  quite  to  the  sternum,  while  the  other  two  project  toward 
the  axilla  and  side,  one  being  lower  than  the  other.     These  are  the  most  common 


THE    MAMMA   OR   BREAST. 


183 


Suspensory  band- 


Pectoral  muscle 


directions  in  which  the  glandular  tissue  is  prolonged,  but  it  may  extend  farther 
than  usual  in  any  direction ;  hence  the  wide  incisions  made  in  cases  of  carcinoma. 

According  to  H.  J.  Stiles  {Ed.  Med.  Joicrn.,  1892,  p.  1099),  the  secreting 
structure  may  extend  posteriorly  into  the  retromammary  tissue  between  the  layers 
of  the  pectoral  fascia.  Anteriorly  it  is  prolonged  with  the  fibrous  tissue  (^ligaments 
of  Cooper)  almost  to  the  skin. 

The  nipple,  located  below  and  to  the  inner  side  of  the  centre  of  the  gland, 
has  connected  with  it  some  circular  and  longitudinal  unstriped  muscular  fibres. 
The  longitudinal  ones  are  attached  to  the  lactiferous  ducts  and  serve  to  retract 
the  nipple,  the  circular  ones  to  erect  it.  Surrounding  the  nipple  is  the  areola. 
It  is  pink  in  the  virgin  and  about  2,5  cm.  in  diameter.  After  pregnancy  its  hue 
becomes  brownish.  The  tubercles  of  AIontgo7nery  are  the  numerous  elevations 
found  on  the  areola.  They  are  more  or  less 
modified  sebaceous  glands  and  enlarge  during 
pregnancy.  As  they  secrete  a  milky  fluid,  they 
are  often  regarded  as  accessory  milk  ducts. 
There  is  no  fat  in  the  nipple  or  areola. 

The  fibrous  structure  of  the  gland 
envelops  the  adipose  and  glandular  tissue. 
It  is  simply  a  continuation  of  the  fibrous  septa 
of  the  superficial  fascia.  These  septa  are  at- 
tached to  the  skin  above,  envelop  and  pass 
between  the  fatty  and  glandular  lobules,  and 
form  a  thin  co\'ering  for  the  under  surface  of 
the  gland.  The  breast  is  sometimes  spoken  of 
as  having  a  capsule,  but  that  simply  refers  to 
the  fibrous  tissue  just  described.  This  fibrous 
tissue  follows  largely  the  ducts,  hence  when 
affected  with  carcinoma  it  contracts  and  draws 
the  nipple  in.  This  forms  the  retracted  nipple 
of  that  disease.  The  fibres  that  go  to  the  skin 
have  been  named  the  ligaments  of  Cooper. 
The  fibrous  tissue  forms  a  net-work  in  the 
meshes  of  which  are  packed  the  glandular 
structure  and  fat-lobules.  It  is  this  which 
gives  the  firmness  and  shape  to  the  virgin 
breast.  In  lactation,  the  fibrous  tissue  softens 
and  stretches  to  accommodate  the  increase  in 
the  glandular  structure  and  this,  with  the  loss 
of  fat,  causes  the  breast  to  become  lax  and 
pendulous.  In  palpating  a  normal  breast  be- 
tween the  fingers  and  the  thumb,  this  firm- 
ness may  feel  like  a  foreign  growth;  hence 
this  method  of  examination  is  not  to  be  relied 
on.  A  better  way  is  to  have  the  patient  re- 
cline, and  lay  the  fingers  flat  on  the  breast, 
compressing  it  on  the  chest-wall  beneath. 
This  flattens  the  glandular  structure  and  any  mass  can  be  more  surely  detected. 

The  fibrous  tissue  between  the  glandular  structure  and  the  pectoralis  beneath 
is  quite  thin  and  loose,  with  large  spaces  in  it  which  have  been  called  the  sjtb- 
mammary  bursa.  Pus  readily  spreads  in  this  loose  submammary  tissue,  but  in  the 
gland  itself  only  with  dilticulty. 

Blood  Supply. — The  breast  is  supplied  with  blood  from  above  by  th&  pectoral 
bra7ich  of  the  acromial  thoracic  artery,  which  leaves  the  axillary  artery  at  the  inner 
border  of  the  pectoralis  minor  muscle.  The  pectoral  branch  descends  between  the 
pectoralis  major  and  minor  and  anastomoses  with  the  intercostals  and  long  thoracic. 
It  sends  branches  through  the  pectoralis  major  muscle,  and  in  carcinoma  of  the  gland 
it  may  be  seen  much  enlarged  running  downward  on  the  chest-wall  beneath  the 
muscle.      From  the  inner  side  come  \\\q.  perforating  brayiches  of  the  internal  mammary 


Gland- 
tissue 


Fascial  envelope 


Fig.  206. — Sagittal  section  of  mamma  of  young 
woman  who  had  never  borne  children;  hardened 
in  formalin.     (Piersol.) 


i84 


APPLIED    ANATOMY. 


artery  from  the  second  to  the  sixth  rib;  the  second,  third,  and  fourth  are  the  largest 
and  may  bleed  freely  in  detaching  the  pectoralis  major.  To  the  outer  side  and 
below  is  the  lo7ig  thoracic  artery,  also  called  the  external  mammary;  it  descends 
along  the  outer  edge  of  the  pectoralis  minor,  sending  branches  inward  around  the 
edge  of  the  pectoralis  major  to  the  mammary  gland.  The  intercostal  arteries  also 
contribute  somewhat  to  the  blood  supply  of  the  gland. 

Lrymphatics. — The  breast  is  exceedingly  well  supplied  with  lymphatics. 
They  are  composed  of  a  deep  set  around  the  lobules  and  ducts,  and  a  superficial  set 
which  together  with  the  deep  lymphatics  forms  a  plexus  around  the  nipple  called  the 
subareolar  plexus.  They  drain  mainly  toward  the  axilla  into  the  lymph-nodes  along 
the  edge  of  the  pectoralis  major  but  also  communicate  with  the  nodes  around  the 
subclavian  artery  and  those  in  the  anterior  mediastinum  which  accompany  the  inter- 
nal mammary  artery. 

The  axillary  nodes  are  in  three  sets:  one  along  the  edge  of  the  pectoralis 
major  muscle  {pectoral  nodes),  another  further  back  along  the  anterior  edge  of  the 
scapula  (^scapular  nodes),   and  a  third  following  the  course  of  the  axillary  artery 


Delto-pectoral  node 


Brachial  node 


Subscapular  node 


Anterior  pectoral  node 

Vessel  passing  to  anterior 

pectoral  node 


Inferior  pectoral  node 


Subclavian  node 


Vessel  passing  to 
subclavian  node 


Intermediate  node 


Subareolar  plexus 
over  mammary 
gland 


Fig.  207. — Lymphatics  of  the  breast.     (Poirier  and  Cun^o.) 

{humeral  nodes).  In  addition  to  these  there  are  some  ififraclavicular  or  subclavian 
nodes  between  the  deltoid  and  pectoralis  major  and  at  the  inner  edge  of  the  pectoralis 
minor  muscles;  these  are  comparatively  rarely  involved  primarily.  The  axillary 
nodes  are  continuous  and  communicate  with  the  subclavian  and  supraclavicular  nodes, 
and  these  latter  are  frequently  enlarged  subsequent  to  the  axillary  infection.  The 
anastomosis  of  the  lymphatics  across  the  median  line  has  been  thought  to  account 
for  the  occurrence  of  the  disease  in  the  opposite  breast  or  axilla.  As  shown  by 
Sappey,  some  if  not  all  of  the  lymphatics  of  even  the  sternal  portion  of  the  breast 
drain  into  the  axilla  and  not  into  the  anterior  mediastinum,  thus  accounting  for  the 
axillary  in\'olvement  when  the  inner  portion  of  the  breast  is  affected.  These  five 
sets  of  nodes  communicate  with  each  other,  and  any  one  may  be  alone  involved. 
The  supraclavicular  set  do  not  become  involved  primarily  because  no  vessels  run 
directly  from  the  breast  to  them;  they  are  affected  secondarily  to  involvement  of  the 
axillary  or  subclavian  sets. 

The  deep  lymphatics  of  the  breast,  according  to  Sappey,  follow  the  ducts  to  the 
areola,  there  anastomosing  with  the  superficial  lymphatics  to  form  what  he  called  the 
subareolar  plexus,  which  drains  by  two  trunks  into  the  axilla.     The  lymphatics  of  the 


THE    MAMMA   OR    BREAST  185 

breast  anastomose  with  those  of  the  surrounding  structures;  hence  in  certain  cases  the 
pectoralis  muscles  and  even  the  pleura  may  be  affected,  and  when  the  disease  is  widely 
disseminated  by  the  lymph-channels  on  the  chest-walls  there  is  produced  the  thick- 
ened, brawny,  infiltrated  condition  known  as  the  cancer  "'en  cuirasse''  of  Velpeau. 
Nerves. — The  breast  and  the  skin  over  it  are  supplied  from  the  descending 
branches  of  the  cervical  plexus,  by  thoracic  branches  from  the  brachial  plexus,  and 
by  the  second,  third,  fourth,  fifth,  and  sixth  intercostals.  These  are  not  of  so  much 
practical  importance  as  the  lateral  branches  of  the  second  and  third  intercostal 
nerves.  That  of  the  second  is  called  the  intercostobt'achialis  (^humeral)  nerve ;  it 
crosses  the  axilla,  anastomoses  with  the  medial  brachial  {^lesser  internal)  cutaneous 
nerve,  and  supplies  the  skin  of  the  inner  and  upper  portion  of  the  arm.  The  third 
intercostal  anastomoses  with  the  second  and  gives  a  branch  to  the  arm  and  to  the 
dorsum  of  the  scapula.  These  nerves  are  certain  to  be  seen  in  clearing  out  the  axilla. 
Their  division  is  accompanied  by  no  paralysis,  but  disturbance  of  them  accounts  for 
some  of  the  pain  and  discomfort  following  the  operation. 

Abscess  of  the  Breast. 

Suppuration  in  the  mammary  gland  is  usually  due  to  infection  which  has 
entered  the  gland  either  through  the  lymphatics  or  the  lactiferous  ducts.  The 
starting  point  of  the  infection  is  thought  to  be  an  ulcerated  crack  or  fissure  of  the 
nipple.  Infection  travelling  into  the  gland  by  way  of  the  lymphatics  would  cause 
pus  primarily  in  the  pericanalicular  tissue  but  it  would  soon  involve  the  lactiferous 
ducts  and  then  pus  might  exude  from  the  nipple.  Infection  travelling  up  the  ducts 
might  reach  the  ultimate  lobules  and  therefore  give  rise  to  widespread  and  multiple 
abscesses.  Suppuration  in  this  gland  resembles  that  in  the  parotid  gland,  already 
described.  When  the  body  of  the  gland  is  involved  it  is  apt  to  be  so  in  more  than 
one  spot.  The  infection  follows  the  branching  of  the  ducts  and  usually  there  are 
several  small  abscesses  instead  of  one  large  one.  If  there  is  a  large  collection  of  pus 
it  is  not  contained  in  one  cavity  but  more  likely  in  several.  This  is  so  often  the  case 
that  in  treating  these  abscesses  it  is  advised  that  they  should  not  only  be  incised  but 
the  finger  should  then  be  introduced  and  the  partitions  separating  the  various  abscess 
cavities  broken  through. 

In  its  incipiency  a  lymphatic  infection  may  cause  a  single  collection  of  pus,  but 
this  soon  breaks  through  into  the  canaliculi  and  infects  and  involves  the  glandular 
structure.  In  an  early  stage  of  duct  infection  several  inflammatory  areas  may  start 
up  about  the  same  time.  The  pus  soon  breaks  through  the  canaliculi  and  involves 
the  periglandular  tissue  so  that  in  each  mode  of  infection  the  condition  soon  becomes 
the  same.  It  is  for  this  reason  that  it  is  difficult  to  say  whether  the  infection  origi- 
nated in  the  lymphatics  or  the  ducts. 

When  the  ducts  are  inflamed  the  pus  often  finds  a  vent  at  the  nipple.  The  fre- 
quency of  this  is  the  reason  why  direct  infection  of  the  ducts  is  regarded  as  the  more 
common  mode.  In  incising  a  mammary  abscess  the  incisions  should  follow  the  course 
of  the  ducts,  that  is,  they  should  be  made  in  a  direction  radiating  from  the  nipple  towards 
the  circumference  and  not  transversely,  otherwise  healthy  ducts  will  be  divided. 

Submammary  Abscess  (for  subpectoral  abscess  see  page  264). — As  has  been 
pointed  out  some  of  the  glandular  tissue  dips  down  to  the  pectoral  fascia,  hence 
when  some  of  these  deepest  lying  lobules  are  inflamed  the  pus  instead  of  breaking 
laterally  into  the  adjoining  lobules  or  tissue  breaks  into  the  submammary  tissue  and 
bursa.  Here  it  spreads  rapidly  beneath  the  gland  and  raises  the  gland  above  it. 
As  the  pus  accumulates  it  sinks  downward  and  works  its  way  outward  to  the  lower 
outer  quadrant  along  the  ^i}^^Q.  of  the  anterior  axillary  fold.  Here  is  where  it  should 
be  opened.      As  the  cavity  is  single  one  incision  is  sufficient  to  drain  it. 

Tumors   of  the   Mammary   Gland. 

Benign  Tumors. — There  are  two  main  kinds  of  benign  mammary  growths, 
cystic  and  adenomatous  or  fibro-adenomatous. 

Cystic  growths  due  to  retention  of  secretion  of  the  ducts  occur  as  small,  rounded 
tumors,  painful  and  tender  to  the  touch,  and  are  seen  between  the  ages  of  25  and  35 


1 86  APPLIED    ANATOMY. 

years.  They  are  not  in  any  way  dangerous.  They  are  composed  of  a  number  of 
dilated  acini.  Another  form  is  degenerati\'e  in  character,  occurring  in  the  decline  of 
life,  and  consists  of  a  large  number  of  various  sized,  usually  small,  cysts  located 
mostly  toward  the  deep  surface  of  the  gland.  They  contain  mucoid  and  degenerated 
material  produced  by  the  lining  membrane  of  the  acini.  The  whole  breast  is  apt  to 
be  studded  with  small  shot-like  cysts  and  both  breasts  are  visually  involved.  This 
affection  in  itself  is  not  malignant,  but  it  may  become  so  by  intracanalicular  growths 
springing  up  from  the  walls  of  the  cysts. 

Adenomatous  growths  are  encapsulated,  usually  single,  and  are  composed  of 
three  distinct  elements.  These  are  glandular  tissue  more  or  less  normal  in  character, 
glandular  tissue  cystic  in  character,  and  fibrous  tissue.  The  fibrous  tissue  forms  the 
capsule  as  well  as  the  stroma  in  the  meshes  of  which  latter  glandular  tissue,  nearly 
normal,  occurs.  These  are  called  fibro-adenoniata  and  if  the  glandular  tissue  is 
quite  abundant  they  may  be  called  adenomata.  If  the  glandular  acini  are  dilated 
so  as  to  overshadow  the  fibrous  portion,  then  it  is  called  a  cystic  adenoma.  These 
cystic  growths  may  be  quite  large. 

Malignant  Tumors. — The  malignant  growths  of  the  breast  are  either  sarco- 
mata or  carcinomata. 

Sarcomata  originate  from  the  fibrous  stroma  of  the  breast  surrounding  the  ducts 
and  acini.  As  it  increases  in  size  it  may  irritate  the  glandular  structure  and  obstruct 
the  ducts,  thus  forming  cysts  which  may  be  quite  large.  Such  a  growth  has  been 
called  a  cystic  sarcoma.  It  also  shows  itself  as  a  single  tumor,  which  may  be  large 
but  solid.  The  lymph- nodes  are  rarely  affected.  The  disease  when  it  wanders 
from  the  seat  of  the  primary  growth  shows  itself  in  some  of  the  internal  organs.  It 
is  disseminated  by  the  blood  and  not  by  the  lymphatics. 

Carciyiomata  originate  from  the  epithelium  lining  the  ducts  and  acini.  For  our 
purposes  we  may  divide  them  into  two  classes,  those  that  grow  into  the  ducts  {intra- 
canalicular^ and  those  that  break  through  the  ducts  and  invade  the  surrounding 
tissues,  of  these  scirrhus  is  the  type. 

Intraca7ialicular growths  have  by  many  authors  been  considered  nonmalignant  on 
account  of  the  rarity  of  their  producing  general  infection.  They  grow  at  times  rapidly 
and  produce  tumors  of  considerable  size.  On  section  they  contain  many  cysts  and 
into  these  cysts,  which  are  derived  from  the  dilated  milk-ducts,  protrude  outgrowths 
from  the  walls.  Sometimes  the  cavity  of  the  cyst  has  its  liquid  contents  replaced  by 
the  solid  tumor  which  has  grown  into  it.  A  discharge  of  bloody  serum  from  the 
nipple  is  common  in  these  growths. 

Scirrhus  is  the  ordinary  form  of  cancer  of  the  breast.  It  starts  in  the  epithelial 
structures  of  the  gland,  breaks  through  the  basement  membrane  and  in\olves  the 
structures  immediately  adjacent  to  it,  and  is  disseminated  more  widely  by  the  lym- 
phatics. Paget  s  disease  is  a  true  carcinoma  which  begins  as  an  eczema  or  ulceration 
around  the  nipple  and  later  becomes  disseminated. 

Carcinoma  follows  the  gland  structure,  and  readily  involves  the  pectoral  fascia 
covering  the  pectoralis  major  muscle.  Anteriorly,  the  gland  structure  in  places 
follows  the  ligaments  of  Cooper  to  the  skin  above,  hence  the  frequency  with  which 
the  skin  is  involved. 

The  scirrhus  variety  does  not  involve  the  ducts  in  the  same  manner  as  does  the 
intracanalicular  variety,  hence  bloody  discharges  from  the  nipple  are  not  so  common 
as  in  that  affection.  The  disease,  when  affecting  the  region  of  the  nipple,  has  been 
considered  more  dangerous  because  of  the  greater  development  of  the  lymphatics, 
particularly  the  subareolar  plexus  of  Sappey,  at  that  point. 

Carcinomatous  disease  extends  especially  by  way  of  the  lymphatics.  These 
follow  the  fibrous  and  canalicular  structure,  therefore  on  section  the  cancerous  tissue 
can  be  seen  extending  like  roots  into  the  surrounding  gland.  This  tissue  shrinks, 
contracts,  and  becomes  harder  as  the  disease  progresses,  that  is  why  retraction  of  the 
nipple  and  dimpling  of  the  skin  occurs.  The  most  free  lymphatic  drainage  occurs 
toward  the  axilla,  not  toward  the  mediastinal  nodes.  The  first  nodes  to  show  infec- 
tion are  those  lying  along  the  edge  of  the  pectoralis  major  muscle  about  the  level  of 
the  third  rib.  Later,  the  nodes  at  the  anterior  edge  of  the  scapula  accompanying  the 
subscapular  artery  become  involved,  or  those  along  the  axillary  vessels.      Still  later 


THE   MEDIASTINUM.  187 

those  along  the  subcla\'ian  vessels  may  be  enlarged  and  may  be  felt  abo\e  the  clavicle 
and  farther  inward  behind  the  sternomastoid  muscle  low  down. 

In  rare  instances  the  disease  may  be  carried  superficially  to  the  subclavian  nodes 
in  the  infraclavicular  triangle  between  the  deltoid  and  pectoralis  major  muscles. 
Should  the  disease  spread,  it  may  be  carried  by  the  lymphatics  to  the  opposite  breast 
directly  across  the  median  line.  If  it  involves  the  lymphatics  of  the  chest-wall  gen- 
erally there  is  produced  the  brawny  condition  of  the  skin  called  cancer  '  V«  C7d?-asse'' 
of  Velpeau  already  alluded  to.  A  cancerous  nodule  beyond  the  edge  of  the  pectoralis 
major  muscle  is  not  necessarily  an  enlarged  node,  but  may  be  due  to  the  involvement 
of  one  of  the  cusps  of  the  gland,  which  sometimes  extend  even  into  the  axilla. 

Removal  of  the  Cancerous  Breast. — The  origin  of  cancer  is  now  believed 
to  be  local  and  not  general  and  the  more  complete  its  removal  the  greater  is  the 
likelihood  of  cure.  Therefore  every  effort  is  made  to  excise  every  possible  infected 
tissue.      This  has  led  to  the  performance  of  very  extensive  operations. 

The  incision  is  made  so  large  as  to  include  nearly  or  quite  all  of  the  skin 
covering  the  glandular  tissue;  this  is  because  of  the  intimate  connection  of  the 
two,  as  already  pointed  out.  It  is  carried  out  to  the  arm;  this  is  to  facilitate 
clearing  out  the  axilla  and  all  its  contents.  The  incision  is  kept  close  to  the  skin; 
this  is  to  avoid  any  glandular  structure  which  may  possibly  be  beneath.  The 
pectoral  fascia  covering  the  pectoral  muscle  is  always  removed. 

Often  both  the  pectoralis  major  and  minor  muscles  are  removed.  In  excising 
them  the  slight  interspace  between  the  clavicular  and  sternal  fibres  of  the  pectoralis 
major  muscle  is  entered  and  the  muscle  detached  from  the  anterior  extremities 
of  the  ribs  and  sternum.  In  so  doing  the  anterior  intercostal  arteries,  particularly 
those  of  the  second,  third,  and  fourth  spaces,  are  liable  to  bleed  freely.  As  the 
pectoralis  major  is  detached  and  turned  outward,  the  acromial  thoracic  artery  is 
seen  at  the  inner  edge  of  the  pectoralis  minor  muscle  with  its  pectoral  branch 
running  down  the  surface  of  the  chest.  This  may  be  ligated,  the  finger  slipped 
beneath  the  pectoralis  minor,  and  this  muscle  cut  loose  from  the  coracoid  process 
above  and  the  third,  fourth,  and  fifth  ribs  below.  At  this  stage  some  operators 
clear  the  subclavian  and  axillary  vessels  of  all  loose  tissues  and  lymph-nodes. 

The  vessels  are  followed  out  on  the  arm.  When  the  insertion  of  the  pecto- 
ralis major  is  reached  it  is  detached  and  the  whole  mass  turned  outward  and  pared 
loose  along  the  anterior  edge  of  the  scapula.  Thus  it  is  removed  in  one  piece. 
The  part  of  the  chest-wall  which  has  been  cleared  off  embraces  from  the  middle 
or  edge  of  the  sternum  to  the  anterior  edge  of  the  scapula  and  from  near  the 
lower  edge  of  the  chest  below  to  the  clavicle  above.  The  vessels  ha\'e  been 
cleared  off  from  the  insertion  of  the  axillary  folds  on  the  arm  to  underneath  the 
clavicle.  Many  operators  make  an  additional  incision  above  the  clavicle  and  clear 
out  the  supraclavicular  fossa  even  if  no  enlarged  glands  can  there  be  detected. 
Sometimes  the  long  thoracic  artery  and  thoracicalis  longus  (long  external  thoracic) 
nerve  may  be  wounded,  but  they  need  not  be.  (See  note,  page  191.) 

Two  nerves  will  be  seen  crossing  the  axilla  from  the  chest  to  the  arm.  They 
are  the  lateral  branches  of  the  second  and  third  intercostal  nerves.  The  second  is 
called  the  intercostobrachialis  (humeral)  nerve.  If  they  can  conveniently  be  spared 
it  is  to  be  done,  otherwise  they  are  divided.  In  clearing  the  axillary  vessels,  small 
veins  and  even  arteries  may  be  divided  close  to  the  main  trunks.  These  may 
be  expected  to  bleed  freely  but  are  usually  readily  secured.  Care  should  be  taken 
not  to  wound  unnecessarily  the  subscapular  artery  and  particularly  the  vein  as  they 
wind  around  the  anterior  edge  of  the  scapula  2  to  3  cm.  below  its  neck.  Some  operators 
prefer  to  detach  the  breast  from  without  in  instead  of  from  within  out  as  described. 

THE  MEDIASTINUM. 

The  mediastinum  is  the  middle  space  of  the  chest  between  the  spine  behind,  the 
sternum  in  front,  and  the  pleurae  to  each  side.  It  is  subdivided  into  a  superior 
inediastin?i))i,  which  is  the  part  above  Ludwig's  angle,  between  the  first  piece  of  the 
sternum  in  front  and  the  vertebrcE  from  the  first  thoracic  to  the  upper  portion  of  the 
fifth  behind.  The  part  below  is  divided  into  the  anterior  mediastinum,  the  middle 
-mediastinutn,  and  ihe. posterior  mediastinum. 


i88 


APPLIED   ANATOMY. 


Superior  Mediastinum. — The  upper  level  of  the  superior  mediastinum  is 
oblique,  as  it  runs  from  the  upper  edge  of  the  sternum  to  the  first  thoracic  vertebra. 
The  lower  level  of  the  superior  mediastinum  runs  from  the  junction  of  the  first  and 
second  pieces  of  the  sternum  to  the  upper  border  of  the  fifth  (or  lower  border  of  the 
fourth  )  thoracic  vertebra.    Laterally  it  is  bounded  by  the  pleurae  and  apices  of  the  lungs. 

The  distance  from  the  anterior  surface  of  the  spine  to  the  posterior  surface  of  the 
sternum  is  quite  small,  being  only  5  to  6  cm.  (2  to  2^  in.).  Through  this  pass 
most  important  structures.  The  trachea  and  oesophagiis  are  in  the  median  line  as  well  as 
the  remains  of  the  thymus  gland.  To  each  side  are  the  great  vessels,  the  innomi7iate 
artery  being  on  the  right  and  the  subclavian  and  carotid  on  the  left.  The  left  innomi- 
nate vein  crosses  transversely  just  below  the  top  of  the  sternum  to  meet  the  innomiyiate 
vein  of  the  right  side  and  form  the  siiperior  vena  cava.  Into  the  innominate  veins 
empty  the  irferior  thyroid^  vertebral,  superior  intercostal,   iiiternal  mammary,  and 


CEsophagus — } 

Innominate  arten,' 
Left  innominate  vein — /-  -4' 
Arch  of  aorta 


Sternum 
Ascending  aorta 

Right  ventricle 
Right  auricle. 

Diaphragm 


— Trachea 


'IV  thoracic  vertebra 


Right  pulmonary 
artery 


.Left  auricle 


—CEsophagus 


Inferior  vena  cava 


Liver 


Spigelian  lobe 


Fig.  208. — The  superior  (red),  anterior  (blue),  middle  (yellow),  and  posterior  (green),  mediastina. 

(Modified  from  Piersol.) 

pericardial  veins  ;  and  into  the  descending  vena  cava  empties  the  vejia  azygos  major. 
On  the  posterior  surface  of  the  oesophagus  and  afterwards  to  its  left  side  passes  the 
thoracic  duct.  The  trachea  bifurcates  opposite  the  junction  of  the  first  and  second 
pieces  of  the  sternum,  and  the  transverse  portion  of  the  arch  of  the  aorta  rises  as  high 
as  the  middle  of  the  manubrium.  The  phrenic  nerves  lie  against  the  pleura,  the 
right  having  the  vena  cava  to  its  inner  side. 

The  right  vagus  {p7ie7imogastric^  7ierve  comes  down  between  the  innominate 
artery  and  vein  and  passes  downward  on  the  posterior  surface  of  the  oesophagus.  It 
gives  its  recurrent  laryngeal  branch  off  at  about  the  right  sternoclavicular  joint. 
The  left  vagus  nerve  comes  down  to  the  outer  side  of  the  left  carotid  artery  and 
goes  over  the  arch  of  the  aorta,  giving  ofT  its  recurrent  laryngeal  branch,  and  thence 
proceeds  to  the  anterior  surface  of  the  oesophagus.     The  presence  of  the  trachea  in 


THE    MEDIASTINUM. 


189 


the  median  line  and  the  edges  of  the  lungs  which  meet  opposite  the  second  rib  give 
a  resonant  percussion  note  to  the  first  piece  of  the  sternum.  With  all  these 
important  structures  crowded  in  the  small  space  between  the  vertebrae  and  sternum 
it  is  easy  to  see  why  tumors  in  this  region  should  cause  serious  symptoms. 

Aneurism  involving  the  arch  of  the  aorta  and  the  great  vessels  is  common. 
Tumors,  such  as  sarcoma,  carcinoma,  and  glandular,  though  rare,  do  occur. 
Abscess  from  high  dorsal  Pott' s  disease  has  been  known  to  cause  serious  effects. 

The  symptoms  of  all  these  affections  resemble  one  another  to  a  considerable 
extent.  Interference  with  the  blood-current,  usually  in  the  veins,  almost  never  in 
the  arteries,  is  marked.  Alteration  in  the  voice  is  produced  by  pressure  on  the 
recurrent  laryngeal  nerves.  Dyspnoea  from  the  pressure  on  the  trachea  and  diffi- 
culty in  swallowing  also  occur,  as  well  as  interference  with  the  circulation  and  the 


Descending 

vena  cava 
Left  pulmonary 

artery 

Left  bronchus 

Left  pulmonary 
veins 


Right  atrium 
(auricle) 


Vagus  nerve 

Internal  jugular  vein 

Common  carotid  artery 

Subclavian  vein 

Left  innominate 
vein 

Phrenic  nerve 

Subclavian  artery 

Vagus  nerve 

Aorta 


Trachea 

Bronchial 

lymph-node 

Pulmonary 

artery 

Pulmonary 

veins 


Right  ventricle 


Fig.  209. — Contents  of  the  mediastina  viewed  from  the  front. 

action  of  the  heart.     The  presence  of  growths  in  this  region  is  indicated  also  by  the 
presence  of  dulness  o\'er  the  region  of  the  manubrium. 

Anterior  Mediastinum. — This  is  the  space  below  the  second  costal  cartilages, 
between  the  sternum  in  front,  the  pericardium  behind,  and  the  two  pleurae  on  the 
sides.  It  is  only  a  narrow  slit  in  the  median  line  above  from  the  second  to  the 
fourth  costal  cartilage;  from  here  the  right  pleura  is  prolonged  obliquely  down  and 
outward  to  the  seventh  costal  cartilage,  which  it  follows.  On  the  left  side  the  pleura 
leaves  the  median  line  about  the  fourth  cartilage  and  passes  out  about  2  cm.  to  the 
left  of  the  sternum  and  then  down  to  the  seventh  costal  cartilage,  which  it  follows. 
The  triangularis  sterni  muscle  arises  from  the  under  surface  of  the  lower  third  of  the 
sternum  and  from  the  xiphoid  cartilage  and  passes  upward  and  outward  to  insert 
into  the  costal  cartilages  of  the  second  to  the  sixth  ribs  inclusive.  The  muscle  lies 
in  front  of  the  anterior  mediastinum  and  the  internal  mammary  artery  runs  down 
between  it  and  the  bone  about  i  cm.  distant  from  the  edge  of  the  sternum.  There 
are  a  few  lymphatic  nodes  in  the  anterior  mediastinum  on  the  diaphragm  below  and 


I  go 


APPLIED    ANATOMY. 


in  the  superior  mediastinum  on  the  arch  of  the  aorta  and  left  innominate  vein  above. 
A  chain  of  nodes  also  accompanies  the  internal  mammary  artery  along  the  edge  of 
the  sternum  between  the  pleura  and  chest  wall. 

Abscess  of  the  anterior  inediastiriiim  may  result  from  infection  due  to  injury  or 
punctured  wounds.  It  may  break  into  the  pleurae  on  the  sides,  into  the  pericar- 
dium posteriorly,  work  its  way  down  toward  the  abdomen,  or  point  in  the  intercostal 
spaces  at  the  edge  of  the  sternum. 

Paracentesis  pericardii  is  performed  in  the  sixth  interspace  close  to  the  sternum; 
also,  the  fifth  and  sixth  cartilages  may  be  resected,  the  internal  mammary  artery 
ligated,  and  the  pericardium  opened  and  even  drained. 

If  one  attempts  to  pass  a  trochar  into  the  pericardium  by  a  puncture  through 
the  fifth  or  sixth  interspace  sufficiently  far  out  to  avoid  wounding  the  internal 
mammary  artery  the  pleura  is  apt  to  be  wounded,  as  it  passes  farther  toward  the 
median  line  than  does  the  lung. 

The  Middle  Mediastinum. — The  middle  mediastinum  is  limited  in  front  by 
the  anterior  wall  of  the  pericardium  and  behind  by  the  posterior  wall  of  the  pericar- 
dium and  roots  of  the  lungs.  It  contains  the  heart  with  the  lower  half  of  the  desce?id- 
ing  vena  cava  and  the  vena  azygos  major  emptying  into  it,  and  the  asce?iding  aorta; 


Thoracic  duct- 
Phrenic  nerve 
Recurrent  laryngeal  nerve 
Common  carotid  artery. 

Bronchial  artery. 
Pulmonary  artery- 


""CEsophagus 
Vagus  nerve 
Phrenic  nerve 

Vena  azygos  major 
■Right  bronchus 

•Right  pulmonary  artery 
Pulmonary  vein 


Left  vagus  nervi 
Left  bronchu: 

Pulmonary  vein 
Aorta- 
Thoracic  duct- 
Vena  azygos  major- 

FiG.  2IO. — Contents  of  the  mediastina  viewed  from  the  rear. 

also  the  structures  forming  the  roots  of  the  lungs,  viz.,  the  right  and  left  bronchi, 
and  \.\\e pnhnonary  arteries  and  veins."^  T\\g phrejiic  nerves  lie  between  the  pericar- 
dium and  pleurae  anteriorly. 

The  bronchial  lymphatic  nodes  are  numerous  between  the  structures  forming  the 
roots  of  the  lungs.  It  is  these  nodes  that  are  so  often  enlarged  in  diseases  of  the 
lungs.  They  are  affected  in  malignant  disease  as  well  as  in  tuberculosis,  etc.  Enlarge- 
ments of  the  heart  pressing  on  the  vessels,  particularly  the  vena  azygos  major,  are 
sometimes  thought  to  cause  pleural  effusions,  especially  if  one-sided. 

When  the  pericardium  is  distended  with  fluid  it  enlarges  more  in  an  up  and  down 
direction,  but  when  the  heart  is  enlarged  its  size  increases  mainly  laterally — from  side 
to  side. 

Posterior  Mediastinum. — The  posterior  mediastinum  extends  from  the  peri- 
cardium and  roots  of  the  lungs  anteriorly  to  the  vertebrae  posteriorly.  The  pleurae 
are  on  each  side.  Behind  the  pericardium  runs  the  oesophagjcs,  lying  in  front  of  the 
aorta,  which  rests  on  the  vertebrae.  In  the  chink  between  the  aorta  and  bodies  of 
the  vertebrae  lies  the  thoracic  duct  and  immediately  to  its  right  side  is  the  vena  azygos 

*  The  mediastina  are  arbitrary  divisions,  and  it  is  a  question  as  to  whether  the  roots  of  the 
kings  should  not  be  included  in  the  posterior  instead  of  the  middle  mediastinum. 


THE    MEDIASTINUM.  191 

major.  The  vena  azygos  minor  is  on  the  left  side  of  the  vertebrae  and  crosses  the 
sixth  to  join  the  vena  azygos  major.  The  descending  thoracic  aorta  is  not  infrequently 
the  seat  of  aneurism. 

Mediastinal  Tumors. — Cancer  is  the  most  frequent  malignant  new  growth,  then 
sarcoma  and  lymphoma.  Great  enlargement  of  the  lymph-nodes  occurs  in  Hodgkiii'' s 
disease  and  is  probably  a  factor  in  causing  a  fatal  issue.  Enlargements  also  result 
from  tuberculosis  and  other  diseases.  They  give  rise  to  pressure  symptoms.  Dyspnoea 
may  be  due  to  pressure  on  the  trachea  or  heart  and  great  vessels.  The  circulation 
may  be  so  much  impeded  that  the  enlargement  of  the  collateral  veins,  especially  those 
of  the  surface,  may  be  \ery  marked.  There  may  also  be  difficulty  of  swallowing  due 
to  pressure  on  the  oesophagus. 

Pleural  Effusions. — Serous  effusions  into  the  pleurae  are  also  known  to  accom- 
pany heart  disease  and  have  been  attributed  in  some  instances  to  obstruction  of  the 
circulation.  They  are  apt  to  be  unilateral  and  are  most  often  found  affecting  the 
right  pleural  cavity.  Baccelli  attributed  the  effusion  to  obstruction  of  the  blood 
current  through  the  vena  azygos  major  ;  the  enlarged  heart  pulling  the  superior  vena 
cava  down  drew  the  vena  azygos  major  tightly  over  the  right  bronchus,  as  is  well 
shown  in  Fig.  210.  Steele  (  Univ.  Med.  Mag.,  1897  ;  Jonrn.  Am.  Med.  Asso.^  1904) 
and  Stengel  (  Univ.  Penna.  Med.  Bulletin,  1901  )  held  that  the  dilated  right  heart  by 
extension  upward  exerts  pressure  on  the  root  of  the  right  lung  and  indirectly  pinches 
the  azygos  major  vein  as  it  curves  over  the  right  bronchus  to  enter  the  superior 
vena  cava.  Fetterolf  and  Landis  (^Am.  Journ.  Med.  Sciences,  1909)  believe  that 
the  fluid  comes  from  the  visceral  pleura  and  not  from  the  parietal  pleura,  and  that  the 
outpouring,  so  far  as  the  pressure  factor  is  concerned,  is  caused  by  dilated  portions 
of  the  heart  pressing  on  and  partly  occluding  the  pulmonary  veins.  They  point  out 
that  Miller  {Am.  Journ.  of  Anat.,  vii)  has  shown  that  the  veins  draining  the  visceral 
pleura  empty  into  the  pulmonary  veins  ;  therefore,  if  these  latter  are  obstructed, 
transudation  may  ensue  ;  this  may  occur  on  either  side.  They  point  out  that  if  the 
right  atrium  (auricle)  dilates,  it  expands  upward  and  backward  and  compresses  the 
left  auricle  and  root  of  the  right  lung;  and  of  the  parts  composing  the  root  the 
pulmonary  veins  are  the  most  anterior,  and,  therefore,  the  ones  most  liable  to  be 
compressed.  Left-sided  effusions  are  accounted  for  by  compression  of  the  left 
pulmonary  vein  by  the  dilated  left  atrium  (which  is  the  most  posterior  of  the  four 
chambers)  and  its  appendix.  The  greater  frequency  of  right-sided  effusions  is  due 
to  the  more  common  occurrence  of  dilatation  of  the  right  side  of  the  heart. 

[VV.  S.  Handley  {Brit.  Med.  Jonrn.,  Oct.  i,  1904)  claims  that  the  principal 
method  of  dissemination  of  carcinoma  of  the  breast  is  not  by  the  lymph  stream  or 
blood  current  but  by  spreading  peripherally  along  the  coarser  meshes  of  the  lym- 
phatic channels  which  exist  in  the  deep  pectoral  fascia.  These  are  continuous  down- 
ward with  the  surface  of  the  recti  muscles. 

He  therefore  advises  that  the  lower  end  of  the  usual  skin  incision  be  prolonged 
downward  and  inward  so  "  that  every  particle  of  the  origin  of  the  great  pectoral  from 
the  rectus  sheath,  and  the  surface  of  the  latter,  on  both  sides  of  the  middle  line, 
should  be  most  carefully  cleared"  as  far  as  two  to  three  inches  below  the  tip  of  the 
ensiform  cartilage.] 


192 


APPLIED    ANATOMY. 


THE  CHEST  CONTENTS. 

For  the  sakt  of  convenience   in  description   and   record,  the   chest  has   been 
divided  into  various  regions  and  marked  by  certain  longitudinal  lines. 

The   Longitudinal   Lines. 

Seven  longitudinal  lines  are  used.    They  run  parallel  with  the  long  axis  of  the  body. 

1.  The  median  line  means  the  midline  of   the  body.     This  runs  down  trie 
middle  of  the  sternum  anteriorly  and  the  middle  of  the  back  posteriorly. 

2.  The  parasternal  line  runs  parallel  to  the  edge  of  the  sternum  and  midway 
between  it  and  the  midclavicular  line. 

3.  The  midclavicular  line,  also  called  the  mammary  line,  is  a  longitudinal 


Fig.  211, — The  longitudinal  lines  of  the  chest  used  in  physical  diagnosis. 

line  passing  through  the  middle  of  the  clavicle.     This  usually  passes  i  to  2  cm. 
internal  to  the  nipple. 

4.  The  anterior  axillary  line  passes  through  the  anterior  fold  of  the  axilla. 

5.  The  midaxillary  line  passes  through  the  middle  of  the  axilla. 

6.  The  posterior  axillary  line  passes  through  the  posterior  fold  of  the  axilla. 

7.  The  scapular  line  passes  longitudinally  through  the  lower  angle  of  the  scapula. 

The   Regions   of   the   Chest. 

In  the  middle  of  the  surface  of  the  chest  anteriorly  there  are  three  regions: 
I.   The  suprasternal  region  is  the  part  above  the  sternum  between  the  sterno- 
mastoid  muscles.      It  is  the  suprasternal  notch. 


THE   CHEST   CONTENTS. 


193 


2.  The  upper  sternal  region  extends  from  the  suprasternal  notch  to  a  line 
drawn  opposite  the  third  costal  cartilages. 

3.  The  lower  sternal  region  is  behind  the  second  piece  of  the  sternum  from 
the  third  costal  cartilages  down. 

Anteriorly  on  the  chest  there  are  four  regions  (Fig.  212)  : 

1.  The  supraclavicular  region,  above  the  clavicle.  This  includes  the  supra- 
clavicular fossa. 

2.  The  infraclavicular  region,  below  the  clavicle  down  to  the  upper  edge  of 
the  third  rib. 

3.  The  mammary  region,  from  the  upper  edge  of  the  third  to  the  upper 
margin  of  the  sixth  rib.  This  extends  from  the  edge  of  the  sternum  to  the  anterior 
axillary  fold  and  has  the  nipple  nearly  in  its  centre. 


-The 


4.   The  inframammary  region  extends  from  the  upper  margin  of  the  sixth 
rib  to  the  lower  margin  of  the  thorax. 

Laterally  on  the  chest  between  the  folds  of  the  axilla  there  are  two  regions: 

1.  The  upper  axillary  region  extends  down  to  the  upper  border  of  the  sixth  rib. 

2.  The  lower  axillary  region  extends  from  the  upper  border  of  the  sixth  rib 
to  the  lower  edge  of  the  thorax. 

Posteriorly  there  are  four  scapular  regions  (Fig.  213)  : 

1.  The  suprascapular  region  is  above  the  spine  of  the  scapula. 

2.  The  scapular  region  is  the  part  covered  by  the  body  of  the  scapula  below 
its  spine. 

3.  The  infrascapular  region  is  the  part  of  the  chest  below  the  scapula  between 
its  angle  and  the  lower  edge  of  the  chest. 

4.  The  interscapular  region  is  the  part  between  the  posterior  edge  of  the 
scapula  and  the  median  line. 

13 


194 


APPLIED    ANATOMY. 


THE   PLEUR/E. 

The  pleurae  form  closed  sacs  which  line  the  thorax  (parietal  pleura)  and  cover 
the  surface  of  the  lungs  (visceral  pleura).  As  the  lungs  expand  and  contract,  the 
pleurae  are  only  completely  in  contact  with  the  lungs  when  the  latter  are  fully  dis- 
tended. In  ordinary  breathing  the  lungs  are  not  completely  expanded,  hence  the 
edges  of  the  pleurae  fall  together  and  so  prevent  the  formation  of  a  cavity.  This 
collapsing  of  the  pleurae  takes  place  mainly  along  its  anterior  and  lower  edges.  The 
apex  of  the  pleura  is  prevented  from  collapsing  by  its  attachment  to  the  first  rib,  and 
also,  as  pointed  out  by  Sibson,  by  the  attachment  to  it  of  an  expansion  of  the  deep 
cervical  fascia  and  some  fibres  of  the  scalenus  anticus  muscle.  Posteriorly  the  chest 
wall  is  unyielding.  Anteriorly  when  the  lungs  are  collapsed  they  fill  out  the  pleurae 
as  low  down   as  the   fourth    costal   cartilage ;   below  that,    in    front   of   the   heart. 


'SUP^^/.^ 


"    /NFRA 
■^       SCAPULAR 
REGION 


a  space  or  sinus  is  left  unoccupied  by  lung.  It  is  called  the  costomediastinal  sinus. 
Likewise  between  the  diaphragm  and  chest-walls  is  another  space,  in  which  the 
parietal  or  costal  and  visceral  layers  of  the  pleura  are  in  contact,^  called  the  costo- 
phrenic  simis  or  complemental  space  of  Gerhardt.  From  these  facts  it  follows  that  the 
outlines  of  the  pleurae  and  lungs  are  identical  posteriorly,  superiorly,  and  anteriorly, 
as  low  as  the  fourth  costal  cartilage.  Here  they  diverge,  the  pleurae  descending 
lower  than  the  lungs. 

The  top  of  the  pleura  is  about  on  a  plane  with  the  upper  surface  of  the  first 
rib.  This  makes  its  posterior  portion  at  the  head  of  the  first  rib  5  cm.  higher 
than  its  anterior  portion  at  the  anterior  end  of  the  first  rib.  The  upper  border 
of  the  clavicle  is  level  with  a  point  midway  between  the  anterior  and  posterior 
ends  of  the  first  rib.  This,  therefore,  shows  the  pleura  to  extend  2.5  cm.  (i  in.) 
above  the  level  of  the  upper  surface  of  the  clavicle. 


THE    PLEURA. 


195 


The  top  of  the  pleura  does  not  project  into  the  neck  in  the  form  of  a  cone,  but 
resembles  a  drum-head,  being  stretched  in  the  form  of  a  plane  almost  or  quite 
level  with  the  top  of  the  first  rib.  Its  upper  surface  is  strengthened  by  fibres  from 
the  deep  fascias  of  the  neck  and,  according  to  Sibson,  by  some  fibres  from  the 
scalene  muscle. 

The  pleura  then  slopes  forward  behind  the  sternoclavicular  joint  to  meet  the 
pleura  of  the  opposite  side  at  the  level  of  the  second  costal  cartilage,  a  little  to  the  left 
of  the  median  line.  They  then  descend  until  opposite  or  a  little  below  the  fourth 
costal  cartilage,  when  they  each  diverge  toward  the  side,  reaching  the  upper  border 
of  the  seventh  costal  cartilage  near  its  sternal  junction.  They  then  slope  down  and 
Out,  reaching  the  lower  border  of  the  seventh  rib  in  the  mammary  line,  the  ninth  rib 


Fig.  214. — .interior  surface  relations  of  the  lungs  and  pleurse. 


in  the  a.xillary  line,  and  the  twelfth  rib  posteriorly  (Joessel  and  Waldeyer,  page  51). 
The  scajDular  line  intersects  the  lower  edge  of  the  pleura  at  about  the  eleventh  rib. 

In  operations  involving  the  lumbar  region,  if  the  incision  is  carried  high  up 
posteriorly  the  pleura  may  be  opened  along  the  lower  border  of  the  posterior 
portion  of  the  twelfth  rib.  It  soon  recedes  from  the  costal  margin  and  in  the 
axillary  line  is  about  6  cm.  (2f  in.)  above  it. 

A  heavy  body,  as  a  bullet,  gravitates  to  the  lowest  portion  of  the  pleural  cavity, 
hence  it  can  be  removed  through  an  incision  in  the  eleventh  interspace  posteriorly. 

(Paracentesis  and  empyema  will  be  alluded  to  after  the  lungs  have  been 
described,  see  p.  200). 


196 


APPLIED    ANATOMY. 


THE   LUNGS 

The  lungs  entirely  fill  the  pleural  sacs  when  completely  distended,  but  only 
partly  so  in  quiet,  ordinary  respiration.  They  are  encased  in  a  bony  cage  that  is 
open  below,  on  account  of  which,  when  the  lungs  distend,  they  expand  mostly 
downward.  To  a  less  extent  they  expand,  in  forced  respiration,  both  laterally 
and  anteroposteriorly,  due  to  the  elevation  of  the  ribs  owing  to  the  traction  of  the 
muscles  upon  them.  Ordinary  breathing  is  performed  mainly  by  the  diaphragm. 
It  acts  like  the  piston  of  a  cylinder  and  as  it  descends  the  air  is  drawn  into  the 
trachea  and  lungs.  As  the  diaphragm  falls  a  negative  pressure  is  produced  within 
the  chest  and  were  it  not  for  its  bony  framework,  it  would  collapse.  The  framework 
is  sufficiently  strong  to  retain  its  shape  in  spite  of  this  pressure  if  the  breathing  is 


Fig.  215. — Posterior  surface  relations  of  the  lungs  and  pleurae. 

normal  and  the  chest-walls  are  healthy.  When,  however,  obstruction  of  the  air- 
passages  is  present,  perhaps  from  enlarged  pharyngeal  or  faucial  tonsils  or  nasal 
hypertrophies,  then  the  deformities  known  as  funnel-breast,  pigeon-breast,  etc., 
already  described,  arise.  They  are  also  produced  if  there  is  no  obstruction  to  the 
breathing  but  only  a  weakness  in  the  bony  thorax,  as  occurs  in  rickets. 

Two  of  the  most  common  of  the  diseases  of  the  lungs  produce  changes  in  the 
shape  of  the  thorax ;  they  are  emphysema  and  phthisis.  Pneumonia,  though  a  frequent 
enough  disease,  does  not  produce  any  changes,  as  it  is  too  short  in  its  duration. 

In  emphysema  the  lungs  are  in  a  state  of  hyperdistention,  hence  they  fill  the 
chest  to  its  greatest  capacity  and  tend  to  make  the  soft  parts  bulge  between  the  ribs. 
In  phthisis  the  lungs  are  contracted,  hence  the  intrathoracic  pressure  becomes  a 
negative  one  and  the  soft  parts  sink  in  between  their  bony  support.  In  emphysema 
the  anteroposterior  diameter  increases  and  the  chest  assumes  the  barrel-form  already 
described.      In  phthisis  it  becomes  lessened  in  its  anteroposterior  diameter  and  we 


THE    LUNGS. 


197 


have  the  flat  chest.  Enlargement  of  the  chest  posteriorly  is  impossible  on  account  of 
the  support  of  the  ribs,  vertebrae,  and  strong  back  muscles.  Enlargement  downward 
is  allowed  by  a  descent  of  the  diaphragm ;  hence  the  fulness  of  the  abdomen  in  those 
affected  with  emphysema  and  conversely  the  flatness  of  the  abdomen  in  those  having 
phthisis.  In  the  region  of  the  apices  the  thorax  is  closed  by  the  deep  fascia,  which 
spreads  from  the  trachea,  oesophagus,  muscles,  and  great  vessels  and  blends  with  the 
pleura  to  be  attached  to  the  first  rib.  In  the  normal  condition  this  is  level  with  the 
plane  of  the  first  rib  and  rises  little  if  at  all  above  it.  Even  in  disease  it  is  not 
materially  altered.  This  is  certainly  so  in  phthisis  and  probably  so  in  emphysema. 
The  apparent  fulness  of  the  supraclavicular  fossae  and  intercostal  spaces  in  emphysema 
and  the  increased  depth  of  these  hollows  in  phthisis  are  not  due  so  much  to  a  bulging 
or  to  a  retraction  of  the  lungs  at  these  points  as  to  the  atrophy  of  the  fatty  and 
muscular  tissue  in  phthisis  and  to  the  muscular  tension  in  emphysema. 

In  coughing,  the  apex  of  the  lung  does  not  jump  up  into  the  neck  above  the 
clavicle  as  it  appears  to  do,  but  remains  nearly  or  quite  below  the  plane  of  the  top  of 
the  first  rib.  The  appearance  of  bulging  is  caused  by  the  movements  of  the  trachea 
in  the  median  line  and  the  muscles  laterally.      This  is  noticeable  particularly  in  the 

Sternothyroid  muscle 

Carotid  artery 

Sternohyoid  muscle 

Subclavian  artery 
Vagus  nerve 


Carotid  artery 


Vagus  nerve 


avian  vein 


First  rib 

Scalenus  anticus 

muscle 

Subclavian  vein 

Subclavian  artery 


Pleura 


First  rib 


Pleura 


Fig.  216. — Upper  end  of  the  thorax,  at  the  level  of  the  first  rib. 

case  of  the  platysma  and  omohyoid  muscles.  In  quiet  breathing  the  posterior  belly 
of  the  omohyoid  lies  about  level  with  the  clavicle,  but  in  coughing  it  rises  i  or  2  cm. 
above  it.  The  intercostal  membranes  and  muscles  are  kept  tense  by  the  constant 
elevation  of  the  ribs  due  to  the  muscular  tension. 


OUTLINE  OF  THE  LUNGS. 

Apex. — The  apex  of  the  lung  has  its  highest  point  opposite  the  posterior 
extremity  of  the  first  rib.  It  then  follows  the  plane  of  the  top  of  the  first  rib  down 
to  the  sternoclavicular  joint,  immediately  above  the  junction  of  the  cartilage  of  the 
first  rib  with  the  sternum.  The  anterior  end  of  the  first  rib  is  5  cm.  lower  than  the 
posterior.  The  upper  edge  of  the  clavicle  is  2. 5  cm.  or  one  inch,  above  the  anterior 
end  of  the  first  rib  and  2.5  cm.  below  the  head  of  the  first  rib,  hence  the  apex  of  the 
lung  rises  2.5  cm.  (i  in.)  above  the  clavicle,  and  it  lies  behind  its  inner  fourth. 
This  distance  will  vary  in  different  individuals  with  the  obliquity  of  the  ribs.  The 
more  oblique  the  ribs  the  greater  will  be  the  distance  between  the  level  of  the  top  of 
the  clavicle  and  that  of  the  neck  of  the  first  rib. 

Anterior  Border. — From  the  sternoclavicular  joint  the  borders  of  the  lungs 
pass  downward  and  inward  until  they  almost  or  quite  touch  in  the  median  line  at  the 
angle  of  Ludwig  opposite  the  second  costal   cartilage.     They  continue  downward 


198  APPLIED    ANATOMY. 

almost  in  a  straight  line  until  opposite  the  fourth  costal  cartilage,  where  they  begin  to 
diverge.  The  border  of  the  right  lung  proceeds  downward  and  begins  to  turn  out- 
ward opposite  the  sixth  cartilage. 

The  left  lung  on  reaching  the  level  of  the  fourth  costal  cartilage  curves  outward 
and  downward  across  the  fourth  interspace  to  a  point  about  2.5  cm.  to  the  inner 
side  of  the  nipple  in  the  fourth  interspace.  From  this  point  it  goes  downward  and 
inward  across  the  fifth  rib  and  interspace  to  the  top  of  the  sixth  rib  about  3  cm.  to 
the  inner  side  of  the  nipple  line.  This  isolated  tip  of  lung  just  above  the  sixth  rib 
over  the  apex  beat  of  the  heart  is  called  the  lingula. 

Lower  Border. — The  lower  edge  of  the  lung  varies  in  different  individuals 
and  in  the  same  individual  according  to  the  amount  of  inflation.  In  quiet  respi- 
ration it  is  about  opposite  the  sixth  cartilage  and  rib  from  the  sternum  to  the  mam- 
mary line,  opposite  the  eighth  in  the  midaxillary  line,  the  tenth  in  the  scapular  line, 
and  the  eleventh  near  the  vertebrae. 

The  Fissures  and  Lobes  of  the  Lungs. — The  left  lung  has  one  fissure  and 
two  lobes,  an  upper  and  a  lower. 

The  right  lung  has  two  fissures  and  three  lobes,  an  upper,  a  middle,  and  a  lower. 

The  fissure  of  the  left  lung  begins  above  and  posteriorly  opposite  the  root  of  the 
spine  of  the  scapula;  this  is  level  with  the  fourth  rib  and  third  dorsal  spine.  It  passes 
downward  and  forward,  ending  at  the  sixth  rib  in  the  parasternal  line.  It  crosses  the 
fourth  in  the  midaxillary  line.  The  lower  lobe  of  the  right  lung  is  of  the  same  size 
as  that  of  the  left  side.  The  lung  above  it  is  divided  into  a  middle  and  upper  lobe. 
The  main  fissure  of  the  right  lung  corresponds  in  its  course  almost'exactly  with  that 
of  the  left  lung.  It  begins  above  and  posteriorly  at  the  root  of  the  spine  of  the 
scapula  and  passing  downward  crosses  the  fourth  rib  in  the  midaxillary  line  and  ends  at 
the  sixth  rib  in  the  mammary  line  (instead  of  the  parasternal  line  as  in  the  left). 

The  subsidiary  fissure  of  the  right  lung  leaves  the  main  fissure  at  the  posterior 
axillary  line  opposite  the  fourth  rib  arid  follows  this  rib  in  an  almost  horizontal  direc- 
tion to  its  junction  with  the  sternum. 

In  order  to  recognize  and  appreciate  the  changes  which  occur  in  the  lungs  in 
lobar  pyieimionia  it  is  necessary  to  know  the  outlines  and  limits  of  the  various  lobes  of 
the  lungs.  A  knowledge  of  the  exact  course  of  the  fissures  of  the  lungs  is  not  only 
necessary  to  outline  the  lobes,  but  it  is  of  service  in  the  diagnosis  of  pleural  effusions. 
These  effusions  often  are  limited  to  certain  localized  areas  instead  of  being  general. 

Pleurisy  may  affect  the  lung  bordering  the  fissures.  When  such  is  the  case,  the 
effusion,  serous  or  purulent,  may  be  in  the  fissure  itself  and  embrace  but  little  of  the  gen- 
eral pleural  cavity.  Dry  taps  from  failure  to  hit  the  purulent  or  serous  collection  are 
not  infrequent,  and  the  possibility  of  its  being  interlobar  should  be  borne  in  mind. 

GENERAL   CONSIDERATIONS. 

From  what  has  been  said  it  follows  that  a  knowledge  of  the  extent  and  outlines 
of  the  lungs  and  of  the  location  and  course  of  the  fissures  is  essential  to  the  proper 
diagnosis  and  treatment  of  affections  of  both  the  lungs  and  pleurae. 

The  extent  of  the  lungs  is  determined  in  the  living  by  percussion.  The  apex  of 
the  lungs  forms  an  oblique  plane  running  upward  and  backward  from  just  below  the 
lower  edge  of  the  inner  extremity  of  the  clavicle  to  the  neck  of  the  first  rib  above 
and  posteriorly.  The  level  of  these  two  points  will  vary  according  to  the  inclination 
of  the  ribs,  which  in  turn  is  influenced  by  the  direction  (vertical)  of  the  spine.  Ordi- 
narily the  distance  is  5  cm.  (2  in.).  It  may  be  even  as  much  as  7  or  8  cm.  The 
top  edge  of  the  clavicle  passes  across  the  middle  of  this  distance  so  that  the  top  of 
the  lung  is  about  2.5  cm.  (i  in.)  above  the  clavicle.  The  highest  point  of  the  lung 
is  not  in  the  middle  of  the  space  enclosed  by  the  first  rib,  but  is  at  its  posterior 
border,  at  the  neck  of  the  first  rib. 

In  percussing,  one  should  not  strike  directly  backward  but  both  downward  and 
backward. 

If  the  patient  is  standing  erect  the  first  rib  will  slope  downward  and  forward  at  an 
angle  of  65  degrees,  or  more,  with  a  vertical  line.  The  spine  will  slope  downward  and 
backward  from  the  same  vertical  line  in  a  normally  straight  back  about  20  degrees. 


THE   LUNGS. 


199 


In  people  with  straight  backs  and  flat  chests  (often  seen  in  phthisis),  the  sloping 
downward  of  the  ribs  is  marked;  in  those  with  rounded  backs  the  chest  is  apt  to  be 
round,  as  in  emphysema,  and  then  the  ribs  are  more  horizontal. 

Another  point  to  be  noticed  is  the  lateral  extent  of  the  apex  of  the  lung  in 
relation  to  the  length  of  the  clavicle.  The  lung  does  not  extend  farther  out  on  the 
clavicle  than  one-fourth  its  length.  The  clavicular  origin  of  the  sternomastoid 
muscle  extends  out  one-third  of  the  length  of  the  clavicle,  so  that  the  lung  is  behind 
the  clavicular  origin  of  the  sternomastoid  and  care  should  be  taken  not  to  percuss 
too  far  out.  If  the  finger  is  laid  in  the  supraclavicular  fossa  in  percussion  it  should 
be  pressed  downward  and  inward,  not  backward. 

Posteriorly  the  scapula  rises  to  the  second  rib  and  its  spine  has  its  root  opposite 
the  fourth  rib  or  spinous  process  of  the  third  thoracic  vertebra.  Therefore  a  small 
portion  of  the  lung  is  above  the  upper  edge  of  the  scapula  and  percussion  in  the 
supraspinous  fossa  gives  a  clear  resonant  note. 

Behind  the  middle  of  the  first  piece  of  the  sternum  passes  the  trachea,  crossed 
by  the  left  innominate  vein.     The  trachea  of  course  contains  air;  the  lungs  slope 


JJ. Normal  lung 


Heart 


Fig.  217. — Formalin-hardened  body,  showing  the  right  lung  collapsed  and  compressed  by  a  large 

pleural  effusion. 

inward  from  the  sternoclavicular  joints  to  meet  nearly  or  quite  in  the  median  line 
and  so  continue  to  the  level  of  the  fourth  rib;  hence  it  follows  that  the  percussion 
note  on  the  sternum  nearly  down  to  this  point  is  resonant  and  if  it  be  found  to  be 
dull  one  should  look  for  an  aneurismal  or  other  tumor  which  is  displacing  or 
covering  the  lungs  and  trachea  at  this  point  and  thereby  subduing  their  resonance. 

Below  the  fourth  rib  the  area  of  the  absolute  heart  dulness  becomes  evident. 
(This  will  be  alluded  to  in  describing  that  organ  later  on. ) 

In  performing  abdominal  operations,  as  those  involving  the  gall-bladder  and 
kidney,  the  surgeon  may  be  tempted  to  prolong  his  incision  upward  into  the  lower 
edge  of  the  chest-walls,  and  it  is  necessary  to  know  how  far  he  can  proceed  without 
opening  the  pleural  cavity.  This  necessitates  his  knowing  how  far  from  the  lower 
edge  of  the  chest  the  pleura  lies.  It  reaches  to  the  seventh  rib  in  the  mammary  line, 
the  ninth  in  the  axillary  line,  and  the  twelfth  posteriorly,  extending  to  its  extreme 
lower  edge. 

In  the  axillary  line  the  pleura  is  about  6  cm.  (2|  in.)  away  from  the  edge  of 
the  thorax.  This  distance  gets  less  as  one  proceeds  forward  to  the  sternum  and 
backward  toward  the  spine. 


200  APPLIED    ANATOMY. 

In  emphysema  the  lung,  being  distended,  occupies  more  nearly  the  outlines  of  the 
pleura  and  its  area  of  resonance  is  increased.  In  pleural  effusion  it  is  compressed  and  even 
sometimes  collapsed.  As  it  shrinks  it  recedes  inward  and  backward  and  is  pushed 
from  the  chest-wall  by  the  layer  of  fluid  (Fig.  217).  The  pressure  of  the  fluid  within 
causes  the  intercostal  spaces  to  be  obliterated  and  sometimes  even  to  bulge  instead  of 
being  depressed.  As  the  expansion  of  the  lung  is  prevented,  the  chest  does  not  move 
on  the  affected  side,  or  expand  with  the  respiration,  as  it  does  on  the  healthy  side. 
This  can  be  demonstrated  by  measuring  the  two  sides  of  the  chest.  At  the  end 
of  expiration  the  affected  side  will  be  from  i  to  3  cm.  greater  in  circumference  than  the 
healthy  one.  If  the  pleural  effusion  is  on  the  right  side  it  may  push  the  heart  to  the 
left  and  raise  its  apex  beat  and  cause  it  to  pulsate  beyond  the  nipple  line  and  even  in 
the  axilla.  If  it  is  on  the  left  side  the  costomediastinal  sinus  (page  196)  becomes 
distended  with  fluid  or  plastic  lymph  and  this  obscures  or  conceals  the  heart's  impulse. 
If  the  effusion  is  very  large  the  heart  is  pushed  over  toward  the  right  and  its  apex 
beat  is  seen  in  the  third  or  fourth  interspace  on  the  right  side  even  so  far  over  as 
the  mammary  line. 

Should  the  effusion  be  purulent  it  may  perforate  the  chest- wall,  or  open  into  the 
pericardium  anteriorly,  the  oesophagus  posteriorly,  and  into  the  stomach  or  peritoneal 
cavity  below.  If  it  perforates  the  chest-wall  it  usually  does  so  anteriorly  between  the 
third  and  sixth  interspaces,  most  often  in  the  fifth. 

Paracentesis. — Where  the  pleural  effusion  is  serous  it  is  usually  drawn  off  by 
an  aspirating  needle  or  trocar. 

For  diagnostic  purposes  a  hypodermic  syringe  needle  is  often  used,  as  the  chest- 
walls  are  usually  thin  enough  to  allow  this  to  be  done,  particularly  if  a  suitable  spot 
is  chosen  and  the  patient  is  a  cnild.  Care  should  be  exercised  not  to  strike  a  rib. 
The  spot  chosen  for  puncture  may  be  indicated  by  dulness  on  percussion.  It  may 
be  anywhere,  but  when  a  choice  is  permissible  the  puncture  should  be  made  in  the 
sixth  interspace  about  in  the  middle  or  postaxillary  line.  Another  preferred  spot  is 
in  the  eighth  interspace,  below  the  angle  of  the  scapula.  The  sixth  interspace  may  be 
determined  in  several  ways,  viz. : 

1.  Begin  at  the  angulus  sterni  (angle  of  Ludwig)  and  follow  out  the  second  rib 
to  the  parasternal  or  midclavicular  line,  thence  count  down  to  the  sixth  rib  and 
follow  it  to  the  midaxillary  line. 

2.  The  nipple  is  in  the  fourth  interspace,  follow  it  to  the  axillary  line  and  count 
two  spaces  down. 

3.  The  apex  beat  of  the  heart  is  in  the  fifth  interspace,  follow  it  around  to  the 
axillary  line  and  take  the  next  space  below. 

4.  Find  the  last  rib  that  articulates  with  the  sternum — it  is  the  seventh ;  follow  it 
around  and  take  the  space  above. 

5.  With  the  arm  to  the  side  the  inferior  angle  of  the  scapula  marks  the  seventh 
interspace;  take  the  interspace  next  above. 

6.  A  horizontal  line  at  the  level  of  the  nipple  cuts  the  midaxillary  line  in  about 
the  sixth  interspace. 

7.  The  lower  edge  of  the  pectoralis  major  touches  the  side  of  the  chest  at  the 
fifth  rib.      Follow  it  to  the  axillary  line  and  go  two  spaces  lower. 

8.  By  raising  the  arm  the  serrations  of  the  serratus  anterior  muscle  attached  to 
the  fifth,  sixth,  seventh,  and  eighth  ribs  become  visible;  that  attached  to  the  sixth  rib 
is  the  most  prominent  and  is  attached  farthest  forward. 

Empyema. — When  the  pleural  effusion  is  purulent,  tapping  is  not  sufficient, 
and  drainage  is  resorted  to.  It  is  not  considered  necessary  to  open  the  pleural 
cavity  at  its  lowest  part  but  the  sites  chosen  are  usually  the  sixth  or  seventh  inter- 
space in  the  mid-  or  postaxillary  line.  The  movements  of  the  scapula  are  apt  to 
interfere  with  drainage  immediately  below  its  angle,  hence  the  opening  is  usually 
made  farther  forward.     The  surgeon  may  or  may  not  resect  a  rib. 

The  ribs  may  lie  so  close  together  as  to  compress  the  drainage-tube;  in  such 
case  a  resection  is  done  if  the  patient's  condition  permits. 

hicision  for  Empye^na. —  In  certain  cases  the  condition  of  the  patient  may 
demand  that  as  little  as  possible  be  done,  and  that  quickly.  The  point  of  operation 
is  selected  by  one  of  the  guides  already  given,  perhaps  the  level  of  the  nipple. 


THE    PERICARDIUM.  201 

While  the  finger  of  one  hand  marks  the  interspace,  an  incision  4  cm.  {i}^  in.) 
long  is  made  along  the  upper  edge  of  the  rib,  this  is  deepened  by  a  couple  of 
strokes  which  detach  the  intercostal  muscles  and  carefully  penetrate  the  pleura. 
As  the  pus  makes  its  appearance  the  knife  is  withdrawn  and  the  finger  is  laid  on 
the  opening.  A  drainage-tube  held  in  a  curved  forceps  is  then  slid  along  the  finger 
into  the  chest.  Sometimes  a  rubber  tracheotomy  tube  is  used  for  drainage  purposes. 
Any  bleeding  will  be  from  the  small  intercostal  branches  and  can  readily  be  stopped 
by  gauze  packing. 

The  incision  is  made  along  the  upper  edge  of  the  rib  because  the  intercostal 
artery  running  along  the  lower  edge  of  the  rib  is  the  larger. 

Resection  of  a  Rib  for  Empyema. — For  the  removal  of  a  part  of  a  rib  a  more 
formal  operation  is  necessary.  The  incision  is  made  directly  on  the  rib  down  to 
the  bone  and  five  or  more  centimetres  in  length.  The  skin  being  retracted,  the 
periosteum  is  incised  and  detached  from  the  rib  with  a  periosteal  elevator  which  is 
passed  down  its  posterior  surface,  pushing  the  pleura  away  from  the  rib.  When 
the  elevator  reaches  the  lower  border  of  the  rib  an  incision  is  made  down  on  it 
through  the  intercostal  muscles,  keeping  as  close  to  the  rib  as  possible  to  avoid 
wounding  the  intercostal  artery,  which  lies  close  to  its  lower  edge.  The  rib  is 
then  divided  either  with  a  cutting  forceps  like  Estlander's,  or  a  Gigli  saw.  The 
rib,  having  been  divided  at  one  end  of  the  incision,  is  then  lifted  up,  the  pleura 
stripped  off,  and  divided  at  the  opposite  end. 

Should  the  intercostal  artery  bleed,  and  it  is  often  sufficiently  large  to  spurt 
quite  actively,  it  can  be  caught  with  a  haemostatic  forceps  and  secured  with  a 
ligature  if  necessary.  This  is  safer  than  to  trust  to  packing,  on  account  of  the 
lack  of  support  due  to  the  removal  of  the  rib.  After  the  incision  is  completed, 
the  pleura  is  incised  and  the  tube  introduced.  In  ligating  the  intercostal  artery, 
care  should  be  taken  not  to  include  the  nerve  which  lies  close  to  but  below  it;  that 
is,  farther  away  from  the  rib. 

THE   PERICARDIUM. 

The  pericardium  is  composed  of  fibrous  tissue  lined  with  a  serous  membrane. 

When  affected  by  inflammation  the  amount  of  fluid  contained  in  it  becomes 
increased  and  it  becomes  distended  and  may  interfere  with  the  functions  of  the  heart 
and  adjacent  structures. 

If  the  efiusion  is  serous  it  is  sometimes  drawn  off  by  puncture;  if  it  is  purulent 
drainage  is  instituted. 

The  pericardium  in  shape  is  somewhat  conical.  Its  base  rests  on  the  central 
tendon  of  the  diaphragm  and  its  apex  envelops  the  great  vessels,  as  they  emerge 
from  the  base  of  the  heart,  for  a  distance  of  4  to  5  cm.  The  attachment  to  the 
diaphragm  is  most  firm  at  the  opening  of  the  inferior  vena  cava.  As  the  fibrous 
layer  of  the  pericardium  proceeds  upward  it  becomes  lost  in  the  fibrous  tissue 
(sheath)  covering  the  great  vessels.  This  is  continuous  above  with  the  deep  cervical 
fascia,  especially  with  its  pretracheal  layer.  Anteriorly  the  pericardium  is  attached 
above  and  below  to  the  sternum  by  the  so-called  sternopericardiac  ligaments  (Fig.  218). 

In  front  of  it  above  are  the  remains  of  the  thymus  gland  and  triangularis  sterni 
muscle  of  the  left  side  from  the  third  to  the  seventh  costal  cartilages.  The  internal 
mammaiy  arteries,  running  down  behind  the  costal  cartilages  about  a  centimetre 
from  the  edge  of  the  sternum  above  and  somewhat  more  below,  are  separated  from 
the  pericardium  by  the  edges  of  the  lungs  and  pleurae,  these  latter  reaching  nearly  or 
quite  to  the  median  line.  The  triangularis  sterni  muscle  also  lies  beneath  the  artery 
and  farther  from  the  surface.  As  the  left  pleura  slopes  more  rapidly  toward  the  side 
than  does  the  right  there  is  a  small  portion  of  the  pericardium  uncovered  by  the  pleura 
at  about  the  sixth  intercostal  space  close  to  the  sternum.  The  incisura  of  the  left 
lung  leaves  a  space  where  the  pericardium  is  separated  from  the  chest-walls  only  by 
the  pleura. 

On  each  side  the  pleura  and  pericardium  are  in  contact,  with  the  phrenic  nerves 
between  them.  Posteriorly  the  pericardium  lies  on  the  bronchi,  the  oesophagus,  and 
the  thoracic  aorta. 


202 


APPLIED    ANATOMY. 


Owing  to  the  fibrous  nature  of  the  pericardium  it  will  not  expand  suddenly. 
While  only  about  a  pint  of  liquid  can  be  injected  into  the  normal  pericardia]  cavity 
after  death,  if  a  chronic  effusion  exists  in  a  living  person  as  much  as  three  pints  may 
be  present. 

Sudden  effusion  occurring  in  the  living  patient  will  cause  obstruction  of  the  cir- 
culation at  the  base  of  the  heart;  it  may  by  pressure  on  the  bronchi  at  the  bifurcation 
produce  suffocative  symptoms  and  by  pressure  on  the  oesophagus  difficulty  in  swallow- 
ing. The  lungs  are  displaced  laterally,  and  the  stomach  and  liver  downward.  The 
largest  effusions  are  slow  in  their  formation. 

Pressure  on  the  left  recurrent  laryngeal  nerve  as  it  winds  around  the  aorta 
sometimes  produces  alteration  or  loss  of  the  voice. 

In  children,  according  to  Osier,  the  praecordia  bulges  and  the  anterolateral  region 
of  the  left  chest  becomes  enlarged  as  does  also  the  area  of  the  cardiac  dulness. 

Paracentesis  of  the  Pericardium. — Tapping  the  pericardium  by  means  of  a 
trocar  or  aspirating  needle  must  be  carefully  done,  or  the  pleura  may  be  punctured. 


Fig.  2i8. —  View  of  the  pericardium,  slightly  distended,  and  its  relations  to  the  bony  thorax. 


The  part  of  the  pericardium  in  contact  with  the  chest-wall  which  is  never  covered 
by  pleura  is  small.  It  embraces  the  space  between  the  two  pleurae  from  the  fourth 
to  the  seventh  ribs.  This  may  be  defined  by  three  lines,  one  in  the  midline,  another 
from  the  middle  of  the  sternum  opposite  the  fourth  rib  to  the  costosternal  junction 
of  the  seventh  rib,  and  a  third  joining  these  two  passing  through  the  articulation  of 
the  xiphoid  cartilage  (Fig.  219). 

The  left  pleural  sac  may  be  i  cm.  distant  from  the  left  edge  of  the  sternum. 
Thus  it  is  seen  that  there  is  hardly  a  point  where  a  needle  can  be  introduced 
with  the  certainty  of  avoiding  the  pleura.  The  safest  point  is  probably  close  to  the 
left  edge  of  the  sternum  in  the  sixth  interspace.  This  interspace  may  not  extend 
to  the  sternum,  but  even  if  the  cartilages  are  in  contact  a  needle  could  probably  be 
introduced  at  this  point.  As  the  pericardium  is  distended  it  carries  the  lungs  and  to 
a  less  extent  the  pleura  outwards  and  increases  the  area  available  for  puncture  both 


THE    PERICARDIUM. 


203 


upward  and  downward  as  well  as  to  the  sides.  When  greatly  distended  the  peri- 
cardium may  reach  to  the  first  interspace  above,  2.5  cm.  (i  in.)  to  the  right  of  the 
sternum,  to  the  seventh  cartilage  below,  and  to  the  left  nipple  line  or  even  beyond. 
The  arching  of  the  diaphragm  causes  a  sternophrenic  sinus  behind  the  sternum  anal- 
ogous to  the  costophrenic  sinus  at  the  lower  edge  of  the  chest.  This  becomes  dis- 
tended by  pericardial  effusions  in  the  same  manner  as  does  the  costophrenic  sinus  in 
pleural  effusions.  A  puncture  in  the  sixth  space  close  to  the  left  edge  of  the  sternum 
enters  this  sinus.  The  increased  area  in  cases  of  distention  from  pericardial  effusions 
has  led  Osier  to  advise  tapping  in  the  fourth  interspace,  either  at  the  left  sternal 
margin  or  2.5  cm.  from  it,  or  at  the  fifth  interspace  4  cm.  (i}4  in.)  from  the  sternal 
margin ;  or  bv  thrusting  the  needle  upward  and  backward  close  to  the  costal  margin 
in  the  left  costoxiphoid  angle. 

It  is  important  to  avoid  wounding  the  internal  mammary  artery,  which  is  usually 


Fig.  219. — Paracentesis  of  the  pericardium. 


nearer  to  the  sternum  above  (0.5  to  i  cm.  to  its  outer  side)  and  farther  from  it  (2  to 
3  cm. )  below. 

The  danger  of  wounding  the  pleura  in  aspirating  with  a  needle  has  probably 
been  overestimated,  but  when  drainage  is  to  be  employed  the  danger  is  certain. 

Drainage  of  the  Pericardium. — To  drain  the  pericardium  requires  the 
removal  usually  of  at  least  one  of  the  costal  cartilages.  A  drainage-tube  can  some- 
times be  introduced  by  first  making  a  short  incision  in  the  fifth  or  sixth  interspace 
close  to  the  left  edge  of  the  sternum,  then  puncturing  the  pericardium,  dilating  the 
puncture  with  forceps,  and  introducing  the  tube.  The  costal  cartilages  usually  lie  so 
close  together  as  to  interfere  with  the  proper  introduction  of  a  tube,  hence  the  neces- 
sity of  resection.  A  flap  may  be  made  or  a  straight  incision.  The  latter  is  some- 
times made  over  the  fifth  costal  cartilage,  which  is  then  resected.  If  desired  the 
sixth  and  seventh  cartilages  are  also  removed  and  even  a  piece  of  the  left  edge  of  the 
sternum.      The  intercostal  muscles  having  been  raised,  the  cartilages  are  removed. 


204  APPLIED    ANATOMY. 

When  the  internal  mammary  artery  is  seen  lying  beneath,  it  is  to  be  either  ligated 
or  drawn  to  one  side.  The  triangularis  sterni  muscle  is  either  incised  or  drawn  to 
the  outer  side  along  with  the  edge  of  the  left  pleura.  The  pericardium  can  then  be 
lifted  with  forceps  and  incised  and  the  drainage-tube  introduced. 

THE  HEART. 

In  size  the  heart  is  somewhat  larger  than  the  clenched  fist.  It  measures  12.5 
cm.  (5  in.)  in  length,  7.75  cm.  (3>^  in.)  in  width,  and  6.25  cm.  (2>^  in.)  in  thick- 
ness. Its  weight  in  the  adult  male  is  250  to  300  Gm.  (8  to  10  oz. ),  in  the  female 
it  is  60  Gm.  (2  oz. )  less. 

It  lies  enclosed  in  its  pericardium  in  the  middle  mediastinum  between  the 
sternum  (from  the  upper  edge  of  the  third  costal  cartilage  to  the  sternoxiphoid  artic- 
ulation) in  front,  and  the  bodies  of  the  fifth,  sixth,  seventh,  and  eighth  thoracic  ver- 
tebrae behind.  Laterally  it  reaches  from  two  centimetres  to  the  right  of  the  sternum 
nearly  to  the  left  nipple  line.  On  each  side  of  it  are  the  lungs,  from  which  it  is 
separated  by  the  pleurae  and  pericardium  with  the  phrenic  nerves  between.  Above 
are  the  great  vessels  and  below  it  rests  on  the  central  tendon  of  the  diaphragm. 

In  shape  the  heart  resembles  an  acorn,  the  atria  {aiiricles),  forming  the  upper 
right  portion  and  the  ventricles  the  lower  left  portion.  It  lies  with  its  right  side 
resting  on  the  diaphragm  and  its  apex  pointing  forward  and  to  the  left. 

For  convenience  one  speaks  of  a  base,  an  apex,  a  right  border,  a  lower  border, 
and  a  left  border. 

OUTLINES  OF  THE   HEART. 

The  base  of  the  heart  is  opposite  the  upper  border  of  the  third  costal  cartilage. 
It  is  here  that  the  superior  vena  cava  ends  and  the  aorta  begins.  It  extends  from 
1.25  cm.  {%  in.)  to  the  right  of  the  sternum  to  2.5  cm.  (i  in.)  to  the  left  of  the 
sternum. 

The  right  border  of  the  heart  extends  from  1.25  cm.  (^  in.)  to  the  right  of  the 
sternum  at  the  upper  border  of  the  third  costal  cartilage  in  an  outwardly  curved  line 
to  the  junction  of  the  seventh  rib  and  the  sternum.  In  the  fourth  interspace  it  may 
reach  2.5  cm,  (i  in. )  beyond  the  right  edge  of  the  sternum. 

The  lower  border  passes  from  the  seventh  right  chondrosternal  junction  across 
the  sternoxiphoid  joint  outward  in  the  fifth  interspace  to  the  apex  beat,  which  is  4 
to  5  cm.  {i}4.  in.  to  i ^  in. )  below  and  to  the  inner  side  of  the  nipple  and  about 
8.75  cm.  {2>%  in.)  to  the  left  of  the  median  line.  This  marks  the  extreme  left  limit 
of  the  heart.  In  children  the  apex  is  higher — it  is  in  the  fourth  interspace.  In  old 
people  it  is  lower. 

The  left  border  arches  upward  from  the  apex  beat,  as  just  given,  in  an  inward 
and  upward  direction  to  2.5  cm.  (i  in.)  to  the  left  of  the  sternum  at  the  upper  border 
of  the  third  costal  cartilage. 

The  atrio-  (auriculo-)  ventricular  groove  or  line  of  junction  between  the  atria 
(auricles)  and  ventricles  runs  from  the  sixth  right  chondrosternal  junction  upward 
and  to  the  left  to  the  third  left  chondrosternal  junction.  The  atria  lie  above  and  to 
the  right  of  this  line  and  the  ventricles  below  and  to  the  left. 

The  right  atrium  (auricle)  and  right  ventricle  lie  anteriorly  and  the  left  atrium 
and  left  ventricle  lie  posteriorly.  In  the  right  atrioventricular  groove  runs  the  right 
coronary  artery.  As  it  lies  on  the  anterior  portion  of  the  heart  it  is  liable  to  be  injured 
in  stab-wounds  and  give  rise  to  fatal  bleeding,  as  may  also  the  interventricular 
branch  of  the  left  coronary  artery  as  it  passes  down  near  the  left  border  of  the  heart 
between  the  right  and  left  ventricles. 

The  Portio7t  of  the  Heart  Uncovered  by  Lung-tisstce. — When  the  lungs  are 
distended  the  right  lung  covers  the  heart  to  the  median  line.  The  left  lung  leaves 
the  median  line  at  the  level  of  the  fourth  costal  cartilage  and  curves  outward  and 
downward  to  about  the  apex  beat  in  the  fifth  interspace,  2.5  cm.  to  the  inner  side  of 
the  nipple  line.  At  this  point  a  small  piece  of  the  lung,  the  lingula,  sometimes 
curves  around  in  front  of  and  below  the  extreme  tip  of  the  heart.  As  the  air  leaves 
the  lungs  they  retract  and  their  anterior  borders  hardly  reach  the  edges  of  the  sternum. 


THE    HEART. 


205 


Area  of  Cardiac  Dulness.— The  area  of  cardiac  dulness  corresponds  to  the 
area  uncovered  by  king  and  in  contact  with  the  chest-wall.  This  is  the  area  of  abso- 
lute dulness.  It  begins  opposite  the  fourth  costal  cartilage  and  extends  down  the 
sternum,  between  the  median  line  and  left  edge,  to  the  liver  dulness  below  opposite 
the  sixth  costal  cartilage.  Toward  the  left  side  it  arches  from  the  fourth  left  costo- 
sternal  junction  to  the  apex  beat.  The  area  of  so-called  relative  dulness  caused  by 
overlapping  of  the  lungs  extends  along  the  right  edge  of  the  sternum  to  opposite  the 
upper  border  of  the  third  rib  above,  and  to  the  left  follows  parallel  to  the  left  border  of 
the  heart  to  the  tip  of  its  apex.     Below  it  blends  with  the  liver  dulness  (Fig.  221). 

The  area  of  cardiac  dulness  may  be  increased  not  only  by  the  enlargement  of  the 
heart  itself  but  by  pericardial  effusions  and  disease  such  as  aneurism  of  the  great  vessels. 

In  an  early  stage  of  pericardial  effusion  and  also  in  aneurism  there  may  be  an 


Fig.  220. — Relations  of  the  heart,  its  valves,  and  the  great  blood-vessels  to  the  surface  of  the  chest. 

extension  of  the  area  of  dulness  upward.      In  a  later  stage  of  pericarditis  the  lateral 
area  of  dulness  becomes  increased. 

Cardiohepatic  Angle  (Ebstein).— This  is  the  angle  formed  by  the  right 
border  of  the  heart  as  it  meets  the  liver.  It  is  a  more  or  less  resonant  area  in  the 
fifth  right  intercostal  space.  Below  it  is  the  liver  dulness  and  above  and  towards 
the  median  line  is  the  heart. 


VALVES  OF  THE   HEART. 

There  are  two  types  of  valves  in  the  heart:  the  bicuspid  {mitral^  and  tricuspid 
between  the  atria  (auricles)  and  ventricles,  and  the  two  sets  of  semilunar  valves  at 
the  entrance  of  the  pulmonary  artery  and  aorta.      (See  Fig.  220.) 

The  bicuspid  valve  is  the  most  important  and  is  the  deepest  seated.  It  lies 
at  the  edge  of  the  left  border  of  the  sternum  opposite  the  fourth  costal  cartilage. 
It  separates  the  left  atrium  and  ventricle  and  lies  nearly  transversely. 


2o6  APPLIED   ANATOMY. 

The  tricuspid  valve  lies  in  the  middle  of  the  sternum  opposite  the  fourth 
intercostal  space.  It  runs  obliquely  downward  and  to  the  right  from  the  third  left 
intercostal  space  to  the  fifth  right  costal  cartilage.  It  separates  the  right  atrium  and 
ventricle. 

The  pulmonary  semilunar  valve  lies  opposite  the  sternal  end  of  the  third  left 
costal  cartilage.  It  is  the  most  superficial  valve  and  the  one  highest  up  on  the  ster- 
num.     It  prevents  regurgitation  of  the  blood  into  the  right  ventricle  from  the  lungs. 

The  aortic  semilunar  valve  lies  under  the  left  side  of  the  sternum  about  level 
with  the  lower  edge  of  the  third  costal  cartilage.  It  is  just  below  and  to  the  right  of 
the  pulmonary  valve,  and  above  and  to  the  left  of  the  bicuspid  valve. 

Location   of   Valvular   Sounds. 

The  sounds  produced  by  the  closure  of  the  valves  do  not  correspond  with  the 
position  of  the  valves,  but  are  as  follows. 

The  bicuspid  sound  is  heard  most  distinctly  at  the  apex  of  the  heart  as  far 
inward  as  the  parasternal  line  and  as  high  as  the  third  interspace.  It  is  transmitted 
around  the  chest  toward  the  axilla. 

The  tricuspid  sound  is  best  heard  at  the  left  sternal  border  between  the  fifth 
and  sixth  costal  cartilages  (Tyson). 

The  pulmonary  sound  is  best  heard  in  the  second  interspace  to  the  left  of  the 
sternum;  the  cartilage  above  is  called  the  pulmonary  cartilage. 

The  aortic  sound  is  best  heard  in  the  second  right  intercostal  space  and  the 
cartilage  above  is  called  the  aortic  cartilage.  The  aortic  sounds  are  transmitted  up 
the  neck  in  the  direction  of  the  great  blood-vessels. 

VARIATION  IN  SIZE  AND  POSITION  OF  THE  HEART. 

The  heart  becomes  enlarged  both  by  being  dilated  and  by  being  hypertrophied, 
usually  both  conditions  are  present;  and  its  position  is  often  changed  by  disease  both 
of  itself  and  of  adjacent  organs.  It  is  apt  to  enlarge  unequally.  In  emphysema  and 
bicuspid  regurgitation  the  right  side  becomes  enlarged,  the  pulmonary  circulation 
being  impeded.  In  aortic  disease,  arteriosclerosis,  muscular  exertion,  or  any  cause 
impeding  the  course  of  the  blood  through  the  arteries  there  is  produced  an  enlarge- 
ment of  the  left  side  of  the  heart. 

The  average  weight  of  the  healthy  heart  is  in  the  male  280  Gm.  (9  oz. ),  and  in 
the  female  250  Gm.  (8  oz. ).  These  may  be  doubled  in  cases  of  enlargement. 
When  the  heart  is  enlarged  the  apex  beat  changes  its  position;  it  may  occupy  the 
sixth,  seventh,  or  eighth  interspace  instead  of  the  fifth,  and  may  be  as  far  as  5  to  7.5 
cm.  (2  to  3  in. )  to  the  left  of  the  nipple  line. 

When  it  enlarges  upward,  instead  of  the  absolute  dulness  beginning  opposite  the 
fourth  costal  cartilage,  it  is  opposite  the  third  or  even  the  second  interspace.  Toward 
the  right  side  the  absolute  dulness  may  extend  a  couple  of  centimetres  beyond  the 
right  edge  of  the  sternum,  instead  of  being  near  its  left  edge  as  is  normal. 

The  heart  is  readily  displaced  by  pressure  from  the  surrounding  structures.  If 
there  is  abdominal  distention  by  gas  or  ascites,  or  if  the  liver  or  spleen  is  enlarged, 
the  heart  is  pushed  upward.  Enlargement  of  the  liver  may  likewise  depress  the 
heart,  if  the  patient  is  in  an  upright  position,  by  the  weight  of  the  liver  dragging  it 
down.  Aneurisms  of  the  arch  of  the  aorta,  tumors,  or  emphysema  may  also  depress 
it.      In  the  aged  the  apex  beat  may  be  normally  in  the  sixth  interspace. 

Lateral  displacement  occurs  in  cases  of  pleural  effusion.  Osier  says  ("  Pract.  of 
Med.,"  p.  594),  this  is  not  due  to  a  twisting  of  the  heart  on  its  axis  but  to  a  positive 
lateral  dislocation  of  the  heart  and  pericardium.  Pneumothorax  or  tumors  on  one  side 
may  also  push  the  heart  toward  the  opposite  side.  It  may  be  pulled  to  one  side  by 
pleural  adhesions  and  in  those  cases  of  fibroid  phthisis  in  which  the  lung  becomes 
markedly  retracted.     Abscess  or  tumors  of  the  mediastinum  also  displace  it. 

The  position  of  the  pulsation  of  the  heart  is  not  always  an  indication  of  the  posi- 
tion of  the  apex.  In  pleural  effusion  the  pulsation  may  be  one,  two,  or  three  inter- 
spaces higher  than  normal,  while  the  apex  itself  may  not  be  elevated. 


THE   HEART. 


207 


WOUNDS   OF  THE   HEART. 

Wounds  of  the  heart  are  usually  immediately  fatal,  but  sometimes  they  are  not 
so.  The  pleurae  are  very  liable  to  be  wounded  at  the  same  time.  The  right  ven- 
tricle, on  account  of  Iving  anteriorly,  is  the  part  most  often  involved.  The  atria  lie 
more  posteriorly  and  are  most  apt  to  be  wounded  in  stabs  through  the  back.  Not 
only  may  the  substance  of  the  heart  itself  be  injured  but  also  its  blood-vessels.  The 
right  coronary  artery  lying  in  the  atrioventricular  groove  and  the  anterior  interven- 
tricular branch  of  the  left  coronary  running  between  the  two  ventricles  anteriorly  are 
the  vessels  most  liable  to  injury.  Owing  to  the  heart  being  enclosed  in  the  peri- 
cardium,— a  closed  sac, — if  blood  accumulates  in  it  the  action  of  the  heart  is  inter- 


FiG.  221. — Percussion  area  of  the  liver  and  heart.    The  light  shaded  area  represents  the  extent  of  deep  or  relative 
dulness  and  the  dark  snaded  area  that  of  superficial  or  absolute  dulness. 

fered  with.  To  avoid  this  occurrence,  wounds  bleeding  externally  should  not  be 
closed,  or  distention  of  the  pericardium  may  ensue. 

Wounds  of  the  heart  have  been  sutured  successfully.  In  order  to  reach  the 
heart,  a  portion  of  the  chest-wall  would  have  to  be  resected  and  turned  to  one  side 
as  a  flap.  This  will  probably  require  the  opening  of  the  pleural  cavity.  The  pleurae 
will  in  all  likelihood  already  have  been  involved  and  found  to  be  filled  with  blood,  as 
has  occurred  in  at  least  one  case. 

A  knowledge  of  the  exact  outlines  of  the  heart  as  already  given  will  often 
enable  one  to  decide  as  to  whether  a  wound  involves  the  heart  or  not. 


2o8  APPLIED   ANATOMY. 


THE  AORTA. 

The  aorta,  as  it  leaves  the  left  ventricle,  begins  under  the  left  portion  of  the 
sternum  opposite  the  lower  border  of  the  third  left  costal  cartilage.  This  is  the 
location  of  the  aortic  semilunar  valves  as  already  given.  It  passes  upward  toward 
the  right  for  5  cm.  and  then  forms  an  arch,  extending  backward  toward  the  left,  to 
reach  the  spine  on  the  left  side  of  the  body  of  the  fourth  thoracic  vertebra.  The 
arch  is  continued  down  in  front  of  the  spine  as  the  thoracic  aorta  and  pierces  the 
diaphragm  in  the  median  line,  between  the  two  crura  of  the  diaphragm,  opposite  the 
twelfth  thoracic  vertebra. 

The  ascending  aorta  begins  behind  the  left  half  of  the  sternum  on  a  level 
with  the  lower  border  of  the  third  costal  cartilage.  It  proceeds  upward  toward  the 
right  until  it  reaches  the  level  of  the  lower  border  of  the  right  second  costal  cartilage, 
where  the  arch  begins. 

Immediately  above  its  commencement  it  has  three  enlargements,  called  the 
sinuses  of  the  aorta  (Valsalva),  which  correspond  to  the  semilunar  valves.  Of 
the  three  semilunar  valves  two  are  anterior  and  one  is  posterior.  From  behind  the 
two  anterior  valves  come  the  right  and  left  coronary  arteries. 

Beyond  the  valves,  in  the  upper  right  portion  of  the  arch,  the  aorta  is  again 
dilated,  forming  the  great  sinus  of  the  arch  of  the  aorta. 

The  right  limit  of  the  aorta  is  about  even  with  the  right  edge  of  the  sternum; 
sometimes  it  projects  slightly  beyond.  When  it  does  so  it  is  liable  to  be  wounded  by 
a  stab  in  the  second  interspace  close  to  the  edge  of  the  sternum.  On  account  of  the 
proximity  of  the  aorta  to  the  second  interspace,  it  is  here  that  the  stethoscope  is  placed 
to  hear  aortic  murmurs.  The  aorta  at  this  point  is  covered  only  by  the  thin  border  of 
the  right  lung  and  pleura  and  the  slight  remains  of  the  thymus  gland.  Below,  its  com- 
mencement is  overlapped  on  the  right  by  the  auricula  dextra  (right  auricular  appendix) 
of  the  atrium  and  on  the  left  by  the  commencement  of  the  pulmonary  artery. 

The  ascending  aorta  is  liable  to  be  the  seat  of  aneurism.  It  may  involve  either 
the  lower  portion  in  the  region  of  the  sinuses  or  the  region  of  the  great  sinus  at  its 
upper  right  anterior  portion. 

If  the  aneurism  enlarges  anteriorly  it  will  show  itself  first  in  the  second  or  third 
interspace.  It  will  bulge  the  ribs  outward  in  this  region.  The  right  lung  will  be 
pushed  outward  and  the  two  layers  of  the  pleura  pressed  together.  It  may  break 
externally  through  the  surface  or  open  into  the  pleural  cavity.  If  it  tends  to  the 
right  it  presses  on  the  descending  cava  and  right  atrium,  thus  interfering  with  the 
return  of  the  blood  from  the  head  and  neck  and  both  upper  extremities.  If  it  en- 
larges to  the  left  or  backward  it  may  press  on  the  right  pulmonary  artery  and 
interfere  with  the  free  access  of  blood  to  the  lungs. 

The  first  portion  of  the  aorta  is  not  united  with  the  pericardium,  but  simply 
loosely  covered  by  it,  so  that  this  portion  of  the  arch  is  weaker  than  the  other  por- 
tions, and  rupture,  with  extravasation  of  blood  into  the  pericardial  sac,  is  not  uncom- 
mon.     An  aneurism  may  also  rupture  into  the  superior  vena  cava. 

The  arch  of  the  aorta  passes  anteroposteriorly  from  the  upper  border  of  the 
second  right  costal  cartilage  in  front  to  the  left  side  of  the  body  of  the  fourth  thoracic 
vertebra  behind.  It  is  about  5  cm.  (2  in.)  long.  Its  under  surface  is  level  with  the 
angle  of  the  sternum  (angle  of  Ludwig),  opposite  the  second  costal  cartilage.  Its 
upper  surface  rises  as  high  as  the  middle  of  the  first  piece  of  the  sternum,  which  is 
opposite  the  middle  of  the  first  costal  cartilage,  about  2.5  cm.  (i  in.)  below  the  top 
of  the  sternum. 

Relations. — In  front  of  the  arch  the  right  lung  and  pleura  cover  it  slightly,  but 
the  left  more  so;  the  remains  of  the  thymus  gland  is  between  them.  The  left  superior 
intercostal  vein  crosses  its  upper  portion  to  empty  into  the  left  innominate  vein.  The 
left  phrenic  and  vagus  nerves  also  cross  it,  the  phrenic  being  the  farther  forward  and 
the  vagus  crossing  almost  in  front  of  the  point  of  origin  of  the  left  subclavian  artery. 
Behind  lie  the  trachea,  oesophagus,  and  thoracic  duct,  also  the  left  recurrent  laryn- 
geal nerve.  The  bifurcation  of  the  trachea  is  directly  behind  and  below  the  lower 
portion  of  the  arch  and  the  left  bronchus  passes  beneath  it.     The  oesophagus  lies 


THE   AORTA. 


209 


compressed  between  the  trachea  and  vertebroe  with  the  thoracic  duct  immediately  to 
the  left.  The  left  recurrent  laryngeal  leaves  the  pneumogastric  on  the  front  of  the 
arch,  then  winds  around  it  and  ascends  between  the  trachea  and  oesophagus  to  reach 
the  larynx  above.  Above,  from  the  upper  surface  of  the  aorta,  are  given  ol?  the 
innominate,  left  carotid,  and  left  subclavian  arteries.  The  left  innominate  vein  crosses 
above  its  upper  edge  to  unite  with  the  right  innominate  to  form  the  superior  cava. 
Below  is  the  left  bronchus  coming  of?  from  the  bifurcation  of  the  trachea,  and  wind- 
ing around  the  arch  is  the  left  recurrent  laryngeal  nerve.  Beneath  the  arch  and 
in  front  of  the  bronchi  are  the  right  and  left  pulmonary  arteries.  From  the  latter  the 
ductus  arteriosus  goes  to  the  arch.  The  cardiac  branches  of  the  pneumogastric  and 
sympathetic  nerves  lie  on  the  anterior,  inferior,  and  posterior  sides  of  the  arch 


Vagus  nerve. 

Common  carotid 

artery 

Internal  jugular  vein 

Subclavian  vein 

Innominate  artery 

Right  recurrent 

laryngeal  nerve 

Right  innominate 

vein 

Phrenic  nerve 


Descending  vena 
cava 


Aorta 


Right  auricle 
(atrium) 


Right  coronary 
artery 


Vagus  nerve 
■Common  carotid  artery 
Internal  jugular  vein 
Subclavian  vein 

Left  innominate  vein 
Phrenic  nerve 


eft  recurrent 
laryngeal  nerve 

Ductus  arteriosus 
Pulmonary  artery 
Left  bronchus 
Pulmonary  veins 


Left  coronary  artery 
Left  ventricle 


Right  ventricle 


Fig.  222. — Heart  and  great  blood-vessels. 

The  ductus  arteriosus  at  birth  is  about  i  cm.  long  and  runs  from  the  pulmo- 
nary artery  to  the  arch  of  the  aorta  below  the  left  subclavian  artery.  It  serves  in  the 
fcetus  to  carry  the  blood  from  the  trunk  of  the  pulmonary  artery  direct  to  the  aorta 
instead  of  passing  into  the  lungs.  When,  after  birth,  the  lungs  are  used  the  ductus 
arteriosus  becomes  obliterated  and  is  found  later  in  life  as  a  cord  running  to  the 
under  side  of  the  arch  of  the  aorta.  Congenital  defects  in  the  heart  are  a  frequent 
cause  of  death  at  birth  and  in  infancy  and  childhood.  They  cause  an  undue  mixture 
of  the  venous  and  arterial  blood  and  give  the  surface  a  dusky,  bluish  hue,  hence  the 
term  "  blue  baby  "  as  applied  to  this  condition.  It  is  due  to  an  absence  of  a  part 
14 


2IO  APPLIED    ANATOMY. 

or  the  whole  of  the  septa  between  the  atria  and  ventricles;  to  a  patulous  condition  of 
the  foramen  ovale  of  the  right  atrium  ;  and  also  to  a  jjersistent  patulous  condition  of 
the  ductus  arteriosus.  Children  so  affected,  if  they  outlive  infancy,  usually  die  before 
reaching  adult  age. 

Aneurism. — This  portion  of  the  aorta  is  also  a  favorite  seat  of  aneurism.  The 
symptoms  produced  will  depend  of  course  on  the  direction  which  the  tumor  takes. 
If  it  tends  anteriorly  it  would  involve  the  lungs  and  pleurae  and  the  phrenic  and  vagus 
nerves,  also  the  sympathetic.  The  displacement  of  the  left  lung  would  be  the  more 
marked.  Involvement  of  the  recurrent  laryngeal  nerve  might  make  a  change  in  the 
voice,  or  there  might  be  disturbances  of  the  pupil  of  the  eye  due  to  implication  of 
the  sympathetic. 

Should  the  tumor  enlarge  posteriorly  the  pressure  on  the  trachea  would  inter- 
fere with  the  breathing.  If  the  tumor  is  large  this  pressure  would  involve  the  oesoph- 
agus and  there  might  be  difficulty  in  swallowing.  Compression  of  the  thoracic  duct 
is  said  to  have  led  to  rapid  wasting. 

If  the  aneurism  bulges  downward  it  impinges  on  the  left  bronchus,  which  may 
lead  to  its  dilation  and  cause  bronchorrhcca.  A  large  tumor  could  also  interfere  with 
the  flow  of  blood  through  the  pulmonary  arteries  and  so  give  rise  to  congestion  and 
dyspnoea. 

An  enlargement  upward  would  involve  the  innominate  and  left  carotid  and 
subclavian  arteries  and  also  the  left  innominate  vein.  Interference  with  the  arteries 
and  veins  of  the  neck  and  upper  extremity  frequently  gives  rise  to  changes  in  the 
pulse  on  the  affected  side  and  also  to  venous  congestion  or  even  oedema.  Changes 
in  the  voice  or  even  its  loss  also  occur.  The  sac  as  it  passes  upward  may  show 
itself  in  the  suprasternal  notch. 

In  all  aneurisms  of  the  arch  cough  is  apt  to  be  a  prominent  symptom.  It  is 
often  paroxysmal.  It  is  to  be  accounted  for  by  pressure  on  the  trachea  or  laryngeal 
nerves.  Difficulty  in  breathing  and  swallowing  may  arise  in  deep-seated  small  tumors 
growing  backward  and  downward.  This  may  be  somewhat  relieved  by  sitting  up  or 
leaning  forward,  while  reclining  or  lying  on  the  back  may  be  unendurable. 

The  great  amount  of  distress  which  these  aneurisms  of  the  arch  of  the  aorta  may 
give  rise  to  is  readily  appreciated  when  one  recalls  that  there  is  only  a  distance  of  5 
or  6  cm.  (2^^  in.)  between  the  upper  edge  of  the  sternum  and  the  anterior  surface 
of  the  vertebral  column,  a  space  already  filled  with  important  structures. 

The  Descending  Aorta. — The  remaining  portion  of  the  aorta,  from  the  lower 
border  of  the  fourth  thoracic  vertebra  down,  is  called  the  desceyiding  aorta.  It  is 
divided  into  the  thoracic  and  abdominal  portions.  The  thoracic  aorta  begins  at  the 
lower  border  of  the  fourth  and  ends  at  the  lower  border  of  the  twelfth  thoracic 
vertebra.  At  its  beginning  it  lies  on  the  left  side  of  the  vertebral  column,  but  as  it 
descends  it  comes  somewhat  forward  but  does  not  reach  the  middle  line.  It  lies  in 
the  posterior  mediastinum  more  toward  the  left  side  than  toward  the  right. 

Relations. — In  front  above  are  the  pericardium,  the  pulmonary  artery,  left  bron- 
chus, left  pulmonary  veins,  and  oesophagus.  Behind  is  the  vertebral  column.  To 
the  right  are  the  oesophagus  above,  the  vena  azygos  major,  and  the  thoracic  duct. 
To  the  left  are  the  left  lung  and  the  pleura,  which  it  grooves,  and  a  quite  small 
portion  of  oesophagus  below. 

Aneurism.,  when  involving  the  thoracic  aorta,  tends  to  cause  absorption  of  the 
vertebrae  and  ribs,  and  to  present  posteriorly;  as  the  space  is  not  so  restricted  as  is 
the  case  higher  up  the  tumor  has  a  freer  opportunity  to  expand  and  the  suffering  is 
not  so  great  nor  are  the  symptoms  so  marked.  It  may  rupture  into  the  left  pleura  or 
oesophagus  and  may  erode  through  the  bodies  of  the  vertebrae  into  the  spinal  canal. 

These  aneurisms  may  exist  many  years  and  attain  a  large  size. 


THE    CESOPHAGUS. 


THE  OESOPHAGUS. 

The  oesophagus  begins  at  the  lower  edge  of  the  cricoid  cartilage,  opposite  the 
lower  border  of  the  sixth  cervical  vertebra,  and  ends  at  the  cardiac  opening  of  the 
stomach,  opposite  the  eleventh  thoracic  vertebra. 

It  is  25  cm.  (10  in.)  long  and  begins  15  cm.  (6  in.)  distant  from  the  teeth.  In 
the  neck  it  inclines  to  the  left,  hence  oesophagotomy  is  performed  on  that  side.  It 
reaches  the  farthest  point  to  the  left  at  the  level  of  the  top  of  the  sternum  or  oppo- 
site the  second  thoracic  vertebra.  It  then  inclines  to  the  right,  reaching  the  median 
line  opposite  the  fifth  thoracic  vertebra.  It  then  again  inclines  to  the  left,  to  pierce 
the  diaphragm  in  front  of  the  aortic  opening  and  to  the  left  of  the  median  line  opposite 
the  tenth  thoracic  vertebra,  and  ends  in  the  cardiac  opening  of  the  stomach  entirely 
to  the  left  of  the  median  line  and  opposite  the  eleventh  thoracic  vertebra  or  tenth 
dorsal  spine.  In  its  passage  through  the  diaphragm  it  is  accompanied  by  the  con- 
tinuation of  the  two  vagi  nerves.  At  its  termination  it  grooves  the  posterior  surface 
of  the  liver. 

Lumen. — The  lumen  of  the  oesophagus  is  narrowed  at  three  points,  (i)  its  com- 
mencement; (2)  where  it  crosses  the  aorta  and  left  bronchus;  and  (3)  near  its  end 
as  it  passes  through  the  diaphragm. 

The  average  diameter  of  the  lumen  is  2  cm.,  which  at  the  upper  and  lower 
constrictions  is  reduced  to  1.5  cm.  The  middle  constriction  is  not  quite  so  marked. 
The  lower  constriction  is  most  marked  at  the  point  of  the  passage  of  the  oesophagus 
through  the  diaphragm;  it  enlarges  slightly  as  it  enters  the  stomach.  This  part  of 
the  oesophagus  is  quite  distensible.  The  next  most  distensible  part  is  opposite  the 
left  bronchus.  This  is  on  a  level  with  the  middle  of  the  first  piece  of  the  sternum  and 
the  third  thoracic  vertebra.  The  upper  constriction  at  the  cricoid  cartilage  is  the 
least  distensible  part  of  the  tube,  so  that  a  body  passing  it  may  pass  entirely  down. 

In  both  living  and  dead  bodies  the  lumen  of  the  oesophagus  is  sometimes  open 
and  sometimes  closed.  In  the  neck  the  pressure  of  the  soft  parts  usually  keeps  it 
closed,  but  frozen  sections  of  the  dead  body  show  it  sometimes  closed  and  sometimes 
open.  Mikulicz  in  using  the  oesophagoscope  has  found  the  lumen  open  in  the  living 
patient  and  been  able  to  see  down  the  remainder  of  the  tube  when  the  instrument  has 
only  been  passed  beyond  the  second  constriction. 

In  passing  an  oesophageal  bougie,  one  should  not  be  used  of  a  larger  diameter 
than  18  mm.  (^  in.).  It  will  enter  the  oesophagus  opposite  the  lower  border  of  the 
cricoid  cartilage  about  15  cm.  (6  in.)  from  the  teeth.  It  will  pass  the  second  con- 
striction 7  cm.  (2^  in.)  farther  on,  opposite  the  middle  of  the  first  piece  of  the 
sternum  or  2. 5  cm.  ( i  in. )  below  its  upper  border,  and  meet  the  third  constriction 
15  cm.  (6  in.)  lower  down,  or  37  cm.  (14.4  in.)  from  the  teeth,  and  enter  the  stomach 
3  cm.  below,  or  40  cm.  (16  inches)  from  the  teeth  and  opposite  the  eleventh  dorsal 
vertebra. 

Relations. — In  the  neck  the  oesophagus  rests  on  the  longus  colli  muscle  and 
vertebrae  behind  and  has  the  trachea  in  front.  On  the  left  side  it  lies  close  to  the 
carotid  sheath,  the  lobe  of  the  thyroid  gland,  and  the  thoracic  duct.  The  left  recurrent 
laryngeal  nerve  is  in  closer  relation  to  it  than  the  right  on  account  of  the  latter 
coming  over  from  the  right  subclavian  artery.  The  left  nerve  lies  on  its  anterior 
surface  near  the  left  edge.  The  right  carotid  artery  lies  farther  from  it  than  does 
the  left.  The  left  inferior  thyroid  artery  is  also  in  closer  relation  to  it  than  the  right 
on  account  of  the  inclination  of  the  oesophagus  to  the  left  side. 

In  the  thorax  it  passes  through  the  superior  mediastinum  between  the  trachea  and 
its  bifurcation  in  front  and  the  aorta  behind. 

In  front  it  has  the  bifurcation  of  the  trachea  and  encroaches  more  on  the  left 
than  on  the  right  bronchus.  The  arch  of  the  aorta  and  the  left  carotid  and  subclavian 
arteries  also  pass  in  front  of  it  and  in  the  posterior  mediastinum  the  pericardium  and 
diaphragm  are  anterior  to  it. 

Posteriorly,  above  it  rests  on  the  spinal  column,  but  below  the  bifurcation  of 
the  trachea  the  aorta  intervenes. 


212 


APPLIED   ANATOMY. 


Vi- 


Laterally  it  is  in  relation  with  the  left  pleura  above  and  the  right  below  and  the 
vena  azygos  major  runs  along  its  right  side  posteriorly.  The  arch  of  the  aorta  winds 
around  its  left  side  at  the  root  of  the  lung.  The  right  vagus  nerve  runs  down  pos- 
teriorly and  the  left  anteriorly,  forming  a  plexus  on  its  surface. 

Dilatation  and   Diverticula. — In  certain  rare  cases  the 

/  oesophagus  becomes  dilated  ;  this  may  involve  the  whole  length 

/  of  the  tube  or  only  its  lower  end.    Obstruction  low  down  may  be 

(  !  a  cause.     It  has  been  known  to  accompany  a  largely  dilated  aorta 

which  pressed  the  oesophagus  against  the  diaphragmatic  opening 

and  so  hindered  the  passage  of  food.     Regurgitation  of  food  is  a 

prominent  symptom  and  liquids  may  regurgitate  from  the  stomach 

and  even  enter  the  mouth. 

Diverticula  are  usually  acquired  and  are  but  seldom  con- 
genital. The  point  of  junction  with  the  pharynx  just  behind  the 
cricoid  cartilage  is  the  most  frequent  seat.  A  sac  is  formed  which 
descends  posteriorly  behind  the  part  of  the  tube  below  and  as  it 
increases  in  size  it  presses  forward  and  may  obstruct  its  lumen. 
Obstruction  from  foreign  bodies,  stricture,  or  disease  of  the  cardiac 
end  of  the  stomach  may  be  a  cause.  Vomiting  is  a  prominent 
symptom  and  the  vomited  material  does  not  show  any  evidences  of 
iM  digestion  or  the  presence  of  acid.    The  existence  of  a  tumor  which 

forms  only  on  deglutition  and  which  can  be  emptied  by  pressure 
is  said  to  be  pathognomonic  of  an  oesophageal  diverticulum. 

Diverticula  have  been  treated  by  washing  out  with  a  stomach- 
tube,  by  excision,  or  if  emaciation  is  rapid  and  marked  by  doing 
a  gastrostomy. 

Carcinoma  and  Stricture. — Carcinoma  is  usually  of  a  flat- 
celled  epitheliomatous  type  and  may  surround  the  oesophagus  like 
a  ring.  The  walls  are  thickened,  a  tumor  forms,  and  the  internal 
surface  may  become  ulcerated.  Stricture  of  the  affected  part  may 
lead  to  the  formation  of  a  dilation  or  diverticulum  above,  and  ulcer- 
ation and  abscess  may  perforate  and  enter  surrounding  organs. 

Dyspnoea  may  arise  from  pressure  on  the  air-passages  and  pus 
may  even  penetrate  them.  Hemorrhage  is  also  sometimes  a  symp- 
tom. It  may  come  either  from  the  inside  or  outside.  In  the  latter 
case  it  may  come  from  the  large  vessels  in  the  neighborhood. 

Septic  inflammation  may  also  be  set  up  in  the  adjacent  pleurae 
and  lungs. 

Foreign  Bodies. — Foreign  bodies  may  become  impacted 
at  any  part  of  its  course;  this  is  particularly  the  case  if  they  are 
hard  and  rough  with  irregular  outlines.  If  they  are  smooth  and 
soft  and  more  or  less  rounded  they  are  apt  to  lodge  at  the  con- 
stricted parts  of  the  tube.  These  points  are,  as  already  stated,  at 
its  commencement,  where  it  crosses  the  aorta  and  left  bronchus, 
and  where  it  passes  through  the  diaphragm.  The  upper  con- 
striction is  1.5  cm.  (or  f  in.)  in  diameter,  and  is  least  distensible. 
It  will  dilate  to  the  width  of  2  cm. ,  and  thus  will  allow  a  body  of 
about  ^  inch  diameter  to  pass.  The  two  lower  constrictions  are 
more  distensible  and  a  body  that  passes  the  oesophagus  can  usually 
pass  the  ileocaecal  valve,  so  that  the  upper  end  of  the  oesophagus 
acts  as  a  gauge  to  prevent  the  entrance  of  substances  too  large  for 
the  rest  of  the  alimentary  tract.  The  bodies  which  become  lodged 
are  usually  those  which  have  been  pushed  down  beyond  the  open- 
ing of  the  oesophagus  by  the  contraction  of  the  muscles  of  the 
pharynx,  and  then  on  account  of  their  irregular  form  become 
caught  by  the  contraction  of  the  tube  below.  With  the  head  mod- 
erately extended,  the  first  constriction  will  be  15  cm.  (6  in.)  from 
the  teeth.  A  foreign  body  at  this  point  will  be  opposite  the  cricoid  cartilage  at  the 
level  of  the  sixth  cervical  vertebra. 


Fig.  223. — The  oesopha- 
gus. From  a  plaster  cast. 


THE    CESOPHAGUS. 


213 


The  second  constriction  is  opposite  the  middle  of  the  first  piece  of  the  sternum. 
This  is  7  cm.  (2^  in.  )  below  the  cricoid  cartilage.  Therefore  a  foreign  body  lodged 
just  above  it  would  be  just  below  the  top  of  the  sternum. 

It  would  be  felt  by  the  probe  22  cm.  (8|  in.  )  from  the  upper  teeth  and  if  cesopha- 
gotomy  was  performed  it  could  usually  be  reached  from  the  wound  in  the  neck. 

The  third  constriction  is  15  cm.  (6  in.)  below  the  second,  or  37  cm.  (i4i  in.) 
from  the  teeth,  and  is  accessible  from  the  stomach.     This  third  constriction  is  more 


Left  common 
carotid 

Vagus  nerve 

Int.  jugular  vein 

Inf.  thyroid  artery 

Vertebral  artery 

Thoracic  duct 

Phrenic  nerve 
Recurrent  laryn- 
geal nerve 
Subclavian  artery 

Bronchial  artery 
Pulmonary 

artery    / , 
Left  vagus  nerve 

Left  bronchu 

Pulmonary  vein 
Aorta 

Thoracic  duct 

Vena  azygos 
major 


Int.  jugular  vein 

Vagus  nerve 

Common  carotid  artery 

Inf.  thyroid  artery 

Vertebral  artery 

Trachea 

Recurrent  laryngeal 

nerve 

CEsophagus 

Right  vagus  nerve 
Phrenic  nerve 

Vena  azygos 

major 

Right  bronchus 

Right  pulmonary 

artery 

Pulmonary  vein 


Fig.  224. — Posterior  view  of  the  oesophagus,  showing  its  relation  to  the  surrounding  structures. 


distensible  than  the  two  above  it.  Maurice  H.  Richardson  was  able,  after  introducing 
the  hand  into  the  stomach,  to  put  two  fingers  into  the  cardiac  opening  from  below, 
and  so  dislodge  some  impacted  false  teeth. 

Foreign  bodies  are  dangerous  on  account  of  the  ulceration  into  the  various  organs 
which  they  cause  and  also  on  account  of  pressure.  Pressure  on  the  left  bronchus  and 
trachea  has  caused  suffocation. 


214  APPLIED    ANATOMY. 

Ulceration  may  cause  fatal  hemorrhage  by  involving  the  carotid  arteries,  more 
likely  the  left,  the  inferior  thyroids,  the  innominate,  and  even  the  aorta  itself  lower 
down.  Low  down  in  the  chest  the  pericardium  is  in  front  of  the  oesophagus,  and 
has  been  perforated.  On  the  left  side  above  and  the  right  side  below,  the  pleura 
have  been  perforated  and  the  lungs  involved.  Abscesses  may  occur  from  the  ulcer- 
ative process  and  they  are  particularly  dangerous,  as  the  distance  between  the  upper 
portion  of  the  sternum  and  anterior  portion  of  the  bodies  of  the  vertebra  is  so  small 
that  compression  of  the  air-passages  and  suffocation  is  readily  produced. 

THE  THORACIC   DUCT. 

The  thoracic  duct  carries  not  only  lyjnph  but  also  chyle  which  is  emptied  into  the 
venous  system  and  goes  to  nourish  the  body.  Therefore  a  wound  of  the  duct  with 
the  escape  of  its  fluid  may  result  fatally  from  inanition.  The  lymph  coming  from  all 
parts  of  the  body  is  collected  into  two  ducts,  the  right  lymphatic  duct  and  the  thoracic 
duct.  Of  these  two  the  right  lytnphatic  dtid  is  the  smaller.  It  collects  the  lymph 
coming  from  the  right  side  of  the  head  and  neck,  right  upper  extremity,  right  side  of 
the  thorax  and  the  upper  convex  surface  of  the  liver.  The  several  lymphatic  branches 
unite  to  form  a  duct,  one  to  two  centimetres  long,  which  empties  into  the  venous 
system  at  the  junction  of  the  right  internal  jugular  and  subclavian  veins.  At  its  point 
of  entrance  it  is  guarded  by  a  pair  of  valves.  As  this  duct  contains  no  chyle,  and 
lymph  of  only  a  portion  of  the  body,  wounds  of  it  have  not  proved  serious. 

The  thoracic  duct  is  much  larger  and  more  important.  It  begins  on  the 
bodies  of  the  first  and  second  lumbar  vertebrae  to  the  right  of  the  aorta  in  the 
cisterna  {receptaculurii)  chyli. 

The  cisterna  or  receptaculum  is  5  to  7.5  cm.  long  and  7  mm.  wide.  It  receives 
not  only  the  lymph  from  the  parts  below  but  also  the  chyle  from  the  intestines.  It 
passes  through  the  aortic  opening  in  the  diaphragm  with  the  aorta  to  the  left  and  the 
vena  azygos  major  to  the  right.  In  the  posterior  mediastinum  it  lies  on  the  bodies 
of  the  seven  lower  thoracic  vertebrae,  with  the  pericardium,  the  oesophagus,  and  the 
arch  of  the  aorta  in  front.  The  thoracic  aorta  is  to  its  left  and  the  vena  azygos  major 
and  right  pleura  to  its  right.  Above  the  fifth  thoracic  vertebra  it  ascends  between  the 
oesophagus  and  left  pleura,  behind  the  first  portion  of  the  left  subclavian  artery. 
On  reaching  the  level  of  the  seventh  cervical  vertebra  it  curves  downward  over  the 
left  pleura,  subclavian  artery,  scalenus  anticus  muscle,  and  vertebral  vein  to  empty 
at  the  junction  of  the  internal  jugular  and  left  subclavian  veins.  It  passes  behind 
left  internal  jugular  vein  and  common  carotid  artery.  At  its  termination  it  lies 
just  external  to  the  left  sternoclavicular  joint  and  just  below  the  level  of  the  upper 
border  of  the  clavicle.      A  punctured  wound  at  this  point  would  injure  the  duct. 

Accompanying  the  veins  of  the  neck  are  numerous  lymph-nodes  which  not 
infrequently  become  enlarged  and  require  removal.  It  is  in  operating  on  these  nodes 
that  wounds  of  the  thoracic  duct  have  been  most  often  produced.  When  divided,  its 
lumen  has  appeared  to  be  of  the  size  of  a  "knitting  needle."  In  some  instances  the 
thin  walls  of  the  duct  have  been  ligated.  In  other  cases  of  injury  either  the  oozing 
point  has  been  clamped  with  a  haemostatic  forceps  which  has  been  left  in  position  for 
a  day,  or  else  the  wound  has  been  packed  with  gauze.      Recovery  usually  ensues. 


THE    THORACIC    DUCT. 


215 


Internal  jugular  vein 


Trachea 

Vertebral  vein 

Right  lymphatic  duct 

Subclavian  vein 
I.  rib 

Right  innominate  vein 


CEsophagus 


Vena  azygos 


Right  lumbar  lymph  trunk 


Crest  of  ilium 


Thoracic  duct 


Aorta 


Left  common  carotid  artery 

Left  innominate  vein 

Thoracic  duct 

Left  subclavian  vein 

Scalenus  anticus 

Left  subclavian  artery 

Thyroid  axis 

L  rib 

Vertebral  artery 


Intercostal  arteries 


Receptaculum  chyli 
Intestinal  lymph  trunk 


Left  lumbar  lymph  trunk 


Crest  of  ilium 


Fig.  225. — Dissection  of  posterior  body-wall,  seen  from  in  front,  showing  thoracic  duct  and  right  lymphatic  duct; 
veins  have  been  laterally  displaced  to  expose  the  terminations  of  the  thoracic  duct.     (Piersol.) 


2l6 


APPLIED   ANATOMY. 


THE  UPPER    EXTREMITY. 

Morphology. — The   human    skeleton  consists  of  two  parts,   called  the  axial 
skeleton  and  the  appendicular  skeleton. 

The  axial  skeleton  embraces  the  bones  of  the  head,  the 
spine,  the  ribs,  the  hyoid  bone,  and  the  breast  bone.  In  the 
spine  are  included  not  only  the  vertebrae  of  the  cervical, 
thoracic,  and  lumbar  regions,  but  likewise  the  sacrum  and 
coccyx. 

The  appendiciilar  skeleton  embraces  the  bones  of  the  limbs, 
or  extremities,  including  the  shoulder-girdle,  formed  by  the 

scapula  and  clavicle,  and  the  pelvic 
girdle,  formed  by  the  innominate  bone 
(Fig.  226). 

Function. — The  upper  extrem- 
ity in  man  is  an  organ  of  prehension. 
As  such,  mobility  is  its  chief  charac- 
teristic. To  permit  of  this  mobility 
the  bones  and  joints  are  many,  and 
the  latter  are  comparatively  loose; 
the  muscles,  also,  are  both  numerous 
and  complex.  Hence  it  is  that  slight 
injuries  are  frequently  followed  by 
considerable  disturbance  of  function. 
They  are  readily  produced  and  with 
difficulty  repaired,  either  by  nature 
or  by  art.  Orthopaedic  surgery  has 
done  much  for  the  disabilities  and  de- 
formities of  the  lower  extremities,  but 
comparatively  little  for  those  of  the 
upper.  An  artificial  leg  in  many  cases 
satisfactorily  substitutes  the  natural 
one,  but  an  artificial  arm  is  compara- 
tively useless. 

The  hand  is  the  essential  part 
of  the  upper  extremity,  and  the  rest 
of  the  limb  is  subsidiary.  If  the  forearm  were  lack- 
ing and  the  hand  were  attached  to  the  end  of  the 
humerus  it  would  still  be  a  very  useful  appendage, 
far  more  so  than  the  stump  which  is  left  after  the  hand 
has  been  amputated. 

The  extremities  proper  are  joined  to  the  trunk  by 
what  are  called  girdles.  The  upper  extremity  is 
attached  through  the  medium  of  the  shoulder-girdle 
and  the  lower  extremity  by  the  pelvic  girdle.  The 
interposition  of  these  girdles  adds  to  the  mobility  of 
the  extremities,  and  as  the  upper  extremity  is  more 
mobile  than  tho  lower  we  find  the  shoulder-girdle  com- 
posed of  two  bones  instead  of  one  as  in  the  pelvic 
girdle  ;  also,  as  the  lower  extremity  bears  the  weight 
of  the  body  it  requires  strength  in  addition  to  mobility, 
hence  we  find  that  it  is  joined  to  the  trunk  by  a  single 
big  strong  bone,  the  innominate,  instead  of  by  two 
comparatively  slight,  narrow  bones  like  the  clavicle 
and  scapula  which  form  the  shoulder-girdle. 

The  extremities  are  termed  appendicular  because 
.r./,'-^-V^-T^^'^^'^^^°\^'T}'T-^      they   are   simply   appendages  to  the   essential  part, 

and  trunk  tormiiiK  the  axial  skeleton  ,  •    1     .  11  1  1  1-  '..U 

and  those  of  the  upper  and  lower  ex-      which  IS  the  head  and  trunk;  z.  persou  can  live  witn- 

fremities  constituting  the  appendicu-  ^         .  •,  • 

lar  skeleton.  out  extremities. 


THE  SHOULDER-GIRDLE. 


217 


THE  SHOULDER-GIRDLE. 

The  upper  extremity  is  joined  to  the  trunk  by  the  shoulder- girdle,  which  is 
composed  of  the  clavicle  and  scapula.  The  main  moxements  are  anteroposterior, 
as  in  swinging  the  arm,  those  of  abduction  and  adduction,  as  in  raising  and  lower- 
ing it  sidewise,  and  rotation. 

The  scapula  is  the  more  important  bone;  it  is  present  in  all  mammals,  and  the 
humerus  articulates  with  it. 

The  scapula  in  the  mole  and  many  other  animals  may  be  a  comparatively 
slender  bone,    but  when,  as  in  man^  it   is   necessary  to   rotate  the  arm,   then  the 


Acromion  process 


Clavicle 


Spine 


Scapula 


Fig.  227. — Shoulder-girdle  of  man. 

scapula  is  large  so  as  to  form  a  strong  support  for  the  infraspinatus,  supraspinatus, 
teres  minor  and  major,  and  subscapularis  muscles. 

The  clavicle  is  developed  mainly  from  membrane,  partly  probably  from  carti- 
lage, and  is  the  first  bone  in  the  body  to  ossify.  It  keeps  the  shoulder  out  away 
from  the  body  and  increases  the  range 
of  motion  of  the  upper  extremity.  It 
owes  its  existence  to  the  function  of 
abduction.  Without  a  clavicle  abduc- 
tion is  practically  wanting  and  when  in 
man  the  clavicle  is  broken,  he  is  tem- 
porarily reduced  to  the  condition  of  those 
animals  which  have  no  clavicles;  he  is 
able  to  move  the  arm  backward  and  for- 
ward but  not  to  elevate  it  properly,  and 
this  is  an  important  diagnostic  symptom 
of  that  injury. 

The  clavicle  is  lacking  in  the  ungu- 
lates or  hoofed  animals.  These  have  an 
anteroposterior  movement,  but  little  abduction.  A  horse  or  cow  mo\'es  its  fore-legs 
back  and  forward,  but  not  out  away  from  the  body.  Hence  its  helplessness  when 
these  movements  are  essential.  It  is  also  lacking  in  seals  and  whales.  In  the 
carnivora,  as  the  Hon  and  the  tiger,  which  possess  rudimentary  clavicles,  sufificient 
adducting  power  is  present  to  enable  them  to  hold  their  food  while  tearing  it  apart. 
In  man,  apes,  bats,  rodents,  and  insectivora  the  clavicle  exists  as  a  well-formed  bone; 


Fig.  228. — Shoulder-girdle  of  man,  showing  how 
the  clavicle  acts  as  a  prop  to  keep  the  shoulder  out  away 
from  the  chest. 


2l8 


APPLIED    ANATOMY. 


hence  they  can  raise  the  arm  well  out  from  the  body  and  even  higher  than  the 
shoulder.  In  the  rodents,  as  the  squirrel,  they  are  enabled  to  hold  a  nut  firmly  in 
the  paws  while  eating  it.  When,  as  in  some  of  the  lower  orders,  the  function  of 
abduction  is  all  important,  we  find  not  only  the  clavicles  present  and,  as  in  the 
common  fowl,  joined,  forming  the  "wish-bone,"  but  in  addition,  in  birds,  there  is  a 
precoracoid  bone  formed  by  the  coracoid  process,  which  is  enlarged  and  continued 
forward  to  articulate  with  the  sternum;  thus  in  flying  animals  there  are  practically 
two  clavicles  on  each  side. 

Affections  of  the   Shoulder. — The  point  of  the  shoulder  projects  well  out 
from  the  side  of  the  thorax.      Hence  it  is  frequently  injured.     As  the  force  is  resisted 


Scapula 


Sternum 


Fig.  229. — Shoulder-girdle  in  birds.  Skeleton  of  an  eagle,  from  the  Wistar  Institute:  the  clavicle,  precoracoid, 
and  scapula  form  the  shoulder-girdle;  the  two  clavicles  have  fused  in  the  median  line,  forming  what  is  commonly 
called  the  "  wish-bone." 


by  the  bones,  these  receive  the  principal  injuries  and  they  are  often  broken.  Frac- 
tures of  the  clavicle  dispute  with  those  of  the  radius  the  distinction  of  being  the 
most  numerous.  Contusions  produce  more  or  less  complete  paralysis  of  the  muscles, 
not  infrequently  through  lesions  of  the  nerves.  The  laxity  of  the  joint  favors  the 
dislocations  to  which  it  is  so  frequently  subject.  It  likewise  becomes  the  seat  of 
tuberculous  disease  requiring  resection.  Crushes  of  the  arm  sometimes  require  its 
removal  at  the  shoulder-joint,  and  occasionally  as  the  result  of  injury  or  disease  opera- 
tions may  be  required  on  the  axillary  lymph-nodes,  nerves,  or  blood-vessels. 

In  order  to  determine  the  character  and  extent  of  injuries  to  the  shoulder,  its 
surface  anatomy  must  be  thoroughly  known.  In  order  to  treat  them,  a  knowledge 
of  the  deeper  structures  and  their  relation  to  one  another  is  essential. 


THE  SHOULDER-GIRDLE. 


219 


The  landmarks  of  the  shoulder  are  formed  by  the  bones  and  muscles;  hence  a 
brief  re\ie\v  of  their  important  characters  will  serve  as  a  basis  for  the  surface  anatomy 
which  follows. 

THE   BONES   OF   THE   SHOULDER. 

The  bones  entering  into  the  construction  of,  and  forming  the  basis  on  which  the 
shoulder  is  constructed  are  the  clavicle  and  scapula,  forming  the  shoulder-girdle,  and 
the  humerus. 

The  clavicle  is  a  comparatively  long  and  slender  bone  that  acts  as  a  prop  to 
keep  the  point  of  the  shoulder  out  from  the  trunk.  The  inner  extremity  is  large  and 
rests  with  its  flat  surface  on  the  upper  outer  edge  of  the  sternum,  with  the  inter- 
position of  a  disk  of  tibrocartilage.     Its  outer  extremity  is  flattened  ;  it  articulates  by 


Trapezius 


Deltoid 


Pectoralis  major 


Fig.  230. — Right  clavicle,  upper  surface. 


means  of  a  gliding  joint  with  the  acromion  process  of  the  scapula,  and  it  is  connected 
with  the  base  of  the  coracoid  process  beneath  by  ligaments.  It  is  double  curved,  the 
large  curve  having  its  convexity  forward  and  embracing  the  inner  two-thirds  of  the 
bone,  and  the  small  curve  having  its  concavity  forward,  forming  the  outer  third. 

At  the  deepest  part  of  the  concavity  of  the  anterior  edge,  about  at  the  junction 
of  its  outer  and  middle  thirds,  is  a  small  rough  eminence  called  the  deltoid  tubercle 
because  of  the  attachment  to  it  of  the  deltoid  muscle.  At  a  corresponding  point  on 
the  posterior  and  under  surface  of  the  bone  is  a  prominent  projection  called  the  conoid 
tubercle ;  to  this  is  attached  the  conoid  ligament.  Running  forward  and  outward 
from  this  tubercle  on  the  under  surface  is  a  rough  line  which  serves  as  the  point  of 


Pectoralis  major 


Subclavius 
Fig.  231. — Right  clavicle,  under  surface. 


Sternohyoid 


attachment  of  the  trapezoid  ligatnent.  Both  these  ligaments  are  of  importance  in 
relation  to  the  fractures  of  this  bone. 

The  middle  third  of  the  bone  is  its  weakest  part.  Attached  to  the  clavicle  on 
its  anterior  surface  are  the  deltoid  muscle  on  its  outer  third  and  the  pectoralis  major 
on  its  inner  half.  On  its  posterior  and  upper  surfaces  are  the  trapezius  at  its  outer 
third,  and  the  clavicular  head  of  the  sternomastoid  on  its  inner  third.  The  subclavius 
muscle  is  attached  to  its  under  surface.  It  will  thus  be  seen  that  there  is  a  space  equal 
to  one-sixth  of  the  length  of  the  bone  inferiorly  and  one-third  of  the  bone  superiorly 
which  is  free  from  muscular  attachments,  and  it  is  here  that  it  is  most  frequently 
fractured. 

The  Scapula. — The  scapula  is  spoken  of  as  having  a  body,  neck,  spine,  and 
acromion,  glenoid,  and  coracoid  processes;  an  upper,  an  anterior,  and  a  posterior  border; 
and  an  upper  and  a  lower  angle.  It  is  not  often  spoken  of  as  possessing  a  head,  the 
glenoid  process  or  that  portion  being  sometimes  so  called  in  which  the  gleyioid  cavity 
or  fossa  for  the  articulation  of  the  humerus  is  situated. 


220 


APPLIED   ANATOMY. 


The  constriction  surrounding  the  head  of  the  scapula  is  known  as  the  anatomical 
neck,  in  contradistinction  to  the  surgical  neck,  which  name  has  been  given  to  that 
portion  indicated  by  a  Hne  drawn  through  the  suprascapular  notch  and  passing 
beneath  the  spine  and  to  the  inside  of  the  attachment  of  the  long  head  of  the  triceps 
muscle  just  belo.w  the  lower  edge  of  the  glenoid  cavity. 

The  angles  and  borders  and  spine  are  important  landmarks  in  physical  diagnosis 
and  the  coracoid  and  acromion  processes  in  injuries. 

In  the  upper  border  of  the  bone  at  its  junction  with  the  base  of  the  coracoid 
process  is  a  deep  notch  called  the  suprascapular  notch  {iyicisura  scapulce),  the  supra- 


Deltoid 


Trapezius 
Supraspinatus 


Omohyoid 


Short  head  of 
biceps  and  coraco- 
brachialis 


Levator  scapula^ 


Rhomboideus  minor 


Infraspinatus 


Rhomboideus  major 


Teres  major 


Latissimus  dorsj 


Fig.  232. — Scapula,  showing  muscular  attachments. 


scapular  nerve  passes  through  it.  The  artery  passes  over  it.  From  the  edge  of  the 
bone  just  behind  the  notch  arises  the  omohyoid  muscle,  an  important  guide  in  opera- 
tions on  the  neck. 

The  body  of  the  scapula  on  its  under  surface  is  flat  and  rests  on  the  thorax  from 
the  second  to  the  seventh  and  nearly  to  the  eighth  rib.  Its  movements  on  the  chest 
are  free  and  follow  those  of  the  arm.  It  rises  and  falls,  glides  forward  and  backward, 
and  also  rotates  on  an  anteroposterior  axis. 

When  using  any  portion  of  the  scapula  as  a  landmark  it  is  customary  to  have 
the  arm  hanging  by  the  side;  if  it  is  otherwise  the  position  of  the  bone  will  be 
changed,  and  the  relations  of  its  projections  to  the  surrounding  parts  are  altered. 
The  scapula  is  sometimes  fractured  directly  across  its  body  below  the  spine.  One 
should  endeavor  to  fix  in  mind  especially  the  relation  of  the  acromion  and  coracoid 
processes  to  the  head,  with  its  glenoid  cavity,  and  the  rest  of  the  bone. 


THE  SHOULDER-GIRDLE. 


231 


Greater  tuberosity. 

Lesser  tuberosity  and 

facet  for  subscapu- 

laris  muscle 

Bicipital  groove 


Surgical  neck 


Fig.  233. — Anterior  surf  ace  of  upper  end  of  humerus. 


The  head  is  comparatively  small  and  cup-shaped,  with  the  glenoid  fossa  on  its 
surface  for  the  head  of  the  humerus.  It  is  joined  to  the  body  of  the  bone  by  a  narrow 
constriction  called  the  neck.  Fractures  through  this  neck  are  rare.  Above  and  pos- 
terior to  the  glenoid  fossa  is  the  acromion  process  and  spine  of  the  scapula,  and  above 
and  anterior  is  the  coracoid  process. 

The  spine  of  the  scapula  runs  upward  and  forward  across  the  upper  and  posterioi 
surface  of  the  bone.     Its  commencement  .  .    ,      , 

,  .  ,  r     1       1  •  11      1  Anatomical  neck 

at  the  posterior  edge  of  the  bone  is  called 
its  root;  this  is  over  the  fourth  rib  and 
opposite  the  third  thoracic  spine.  The 
posterior  edge  of  the  scapula  opposite 
the  root  of  the  spine  projects  backward, 
but  this  is  not  the  superior  angle,  which  is 
still  higher  up.  The  spine  of  the  scapula 
ends  anteriorly  in  the  acromion  process. 
This  projects  far  beyond  the  glenoid  cav- 
ity, overhangs  the  head  of  the  humerus, 
and  forms  the  point  of  the  shoulder.  It, 
as  well  as  the  rest  of  the  spine,  is  subcu- 
taneous and  is  a  valuable  landmark. 

The  acromion  process  is  not  so  often 
fractured  as  one  would  expect.  It  articu- 
lates with  the  clavicle  and  the  bones  are 
not  infrequently  luxated  at  this  point. 

The  coracoid  process  projects 
forward  underneath  the  clavicle  to  the 
upper  and  inner  side  of  the  head  of  the 
humerus.  It  is  about  2.5  cm.  (i  in.) 
below  the  clavicle  and  just  to  the  outer 
side  of  the  junction  of  its  middle  and  outer  thirds.  It  lies  just  underneath  the  inner  edge 
of  the  deltoid  muscle,  hence  it  is  not  always  easily  felt.  It  is  almost  never  fractured, 
but  is  especially  valuable  as  a  landmark  in  injuries  and  operations  on  the  shoulder. 

The  two  great  hollows  above  and  below  the  spine  are  the  supra-  and  infraspinous 
fossa  for  the  supra-  and  infraspinatus  muscles.    The  angles  are  at  the  two  extremities 

of  the  posterior  border.  The 
superior  angle  receives  the  in- 
sertion of  the  levator  scapulae 
muscle  and  is  covered  by  the 
trapezius  which  inserts  into  the 
spine  and  thus  obscures  its  out- 
line. The  inferior  angle  is  cross- 
ed by  the  upper  edge  of  the 
lattssimus  dor  si  muscle,  from 
which  it  sometimes  receives  a 
few  fibres.  This  angle  is  ren- 
dered prominent  when  the  fore- 
arm is  flexed  on  the  arm  and 
placed  across  the  back. 

The  Humerus . — The 
upper  end  of  the  humerus  is 
composed  of  a  head  joined  to 
the  tuberosities  through  the 
medium  of  the  anatomical  neck. 
The  head  projects  inwardly  from 
the  shaft  at  an  angle  of  1 20  degrees  to  it.  The  lesser  tuberosity  has  inserted  into  it 
the  subscapularis  muscle;  it  presents  forward.  To  its  outer  side  and  separating  it 
from  the  greater  tuberosity  is  the  bicipital  groove  for  the  long  tendon  of  the  biceps 
muscle.  To  the  outer  side  of  the  groo\'e  is  the  greater  tuberosity  with  its  three  facets 
for  the  supraspinatus,  infraspinatus,  and  teres  minor  micscles. 


Anatomical  neck 
Facet  for  infra- 
spinatus muscle 
Facet  for  teres 
minor  muscle 

Surgical  neck 


Facet  for  supra- 
spinatus  muscle 
Bicipital  groove 

Greater  tuberosity 
Lesser  tuberosity 


Fig.  234. — Outer  surface  of  upper  end  of  humerus. 


222  APPLIED    ANATOMY. 

The  greater  tuberosity  projects  considerably  beyond  the  acromion  process  and 
therefore  forms  the  most  prominent  part  of  the  shoulder.  Immediately  below  the 
tuberosities  is  the  surgical  neck.  It  is  described  as  being  the  portion  between  the 
tuberosities  above  and  the  insertions  of  the  pectoralis  major  and  latissimus  dorsi 
muscles  below.  It  is  a  connnon  site  for  fractures.  Half  way  down  the  shaft  on  its 
outer  side  is  the  rough  deltoid  eminence  for  the  insertion  of  the  deltoid  muscle. 

Sternoclavicular  Joint. — The  ligaments  uniting  the  inner  end  of  the  clavicle 
to  the  thorax  at  the  upper  end  of  the  sternum  are  the  interclaviciilar,  which  passes 
from  one  clavicle  to  the  other  across  the  top  of  the  sternum,  the  anterior  2Lwdi posterior 
sternoclavicular,  and  the  rhomboid  or  costoclavicular  ligament  which  passes  from  the 
clavicle  downward  and  forward  to  the  first  rib.  This  last  one  limits  displacement  in 
cases  of  luxation.  There  is  a  fibrocartilaginous  disk  between  the  clavicle  and  sternum, 
forming  two  distinct  joint  cavities.    The  line  of  the  joint  slopes  downward  and  outward. 

Acromioclavicular  Joint. — The  outer  end  of  the  clavicle  articulates  with  the 
acromion  process  by  a  joint  whose  surface  inclines  down  and  inward,  thus  favoring 
displacements  of  the  clavicle  upward.  The  ligaments  joining  them  are  called  the 
superior  and  inferior  acromioclavicular.  In  reality  they  are  simply  the  thickened 
portions  of  the  capsular  ligament.  This  capsular  ligament  is  ruptured  in  the  not  infre- 
quent cases  of  luxation  which  occur  here.  Running  from  the  under  surface  of  the 
clavicle,  a  short  distance  from  its  outer  end,  to  the  coracoid  process  below,  is  the 

Anterior  sternoclavicular  Costoclavicular  or  rhomboid  ligament 

Interclavicular  ligament  /  /  Clavicle 

Interarticular  fibrocartilage 


Tendon  of 
subclavius  muscle 


First  rib 


First  piece  of  sternum 
Fig.  23s. — Sternoclavicular  joint  and  attachments  of  the  inner  end  of  the  clavicle. 

coracoclavicular  ligament.  It  is  composed  of  two  parts,  an  antero-external  square 
ligament  called  the  trapezoid,  and  a  postero-internal  conical  one  called  the  co7ioid. 

The  bone  may  be  fractured  just  external  to  these  ligaments,  giving  rise  to  a  peculiar 
deformity  to  which  attention  will  be  called  in  describing  the  fractures  of  the  clavicle. 

From  the  coracoid  process  the  coraco-acromial  ligament  runs  outward  and  up- 
ward to  the  acromion  process,  the  coracohumeral  outward  and  downward  to  the  neck 
of  the  humerus,  and  the  costocoracoid  ligament  inward  to  the  first  rib  at  its  cartilage. 

The  Shoulder-joint. — The  upper  extremity  being  an  organ  of  prehension  and 
not  of  support,  the  shoulder-joint,  which  is  the  articulation  which  connects  it  with  the 
trunk  through  the  shoulder-girdle,  is  constructed  with  the  idea  in  view  of  favoring 
and  permitting  motion,  and  not  of  supporting  weight  or  resisting  force.  Hence  we 
find  it  to  be  a  ball-and-socket  joint,  the  one  which  allows  of  the  freest  movements. 

The  glenoid  cavity  is  a  shallow  excavation,  not  a  deep  cup,  as  in  the  hip.  The 
articulating  surface  of  the  head  of  the  humerus  is  extensive  but  not  so  large  as  it 
would  have  been  had  the  scapula  not  been  made  to  move  on  the  thorax.  The 
clavicle  keeps  the  joint  well  out  from  the  side  of  the  body;  hence  the  neck  of  the 
humerus  is  short.  The  movements  of  the  arm  are  so  extensive  and  free  that  we  do 
not  have  the  tuberosities  of  the  humerus  so  large  and  set  so  far  away  from  the  artic- 
ular surface  as  is  the  case  with  the  femur  and  its  trochanters. 

If  the  upper  portion  of  the  femur  was  like  the  upper  end  of  the  humerus,  the 
lower  extremity  would  be  continually  rolling  in  or  out,  making  walking  or  running 
at  least  difficult  if  not  impossible.  Thus  we  see  that  the  shape  of  the  bones  is 
dependent  on  the  character  of  their  functions.. 


THE  SHOULDER-GIRDLE. 


223 


The  ligaments  of  the  joints  are  inelastic  tissues;  hence  those  that  enter  into  the 
construction  or  a  movable  joint  must  be  loose,  and  the  more  movable  a  joint  is,  the 
more  does  its  security  depend  not  on  its  ligaments,  but  on  its  muscles. 

The  shoulder-joint,  like  other  joints,  has  a  capsular  ligament  which  is  attached 
to  the  adjacent  bones  and  serves  to  keep  the  lubricating  synovial  fluid  applied  to  the 
articulating  surfaces.  In  certain  positions  this  ligament  may  also  ser\'e  to  a  limited 
extent  to  keep  the  ends  of  the  bones  of  the  joint  in  contact. 

Besides  this  capsular  ligament  there  are  fibrous  bands  which  strengthen  it  at 
certain  places  as  they  pass  from  adjacent  processes  of  bone  on  one  side  of  the  joint 


Superior  acromioclavicular  ligament 


Tendon  of  supra 
spinatus  muscle 


Acromion  process 


Clavicle 


Conoid  ligament 
Trapezoid  ligament 

Coraco-acromial  ligament 
Coracoid  process 

Coracohumeral  ligament 
Coracobrachialis  muscle 
Short  head  of  biceps 


Long  head  of  biceps 


Pectoralis  major  muscle 


Fig.  236. — Acromioclavicular  and  shoulder  joints. 


to  those  on  the  other.  The  muscles  and  their  tendons  pass  across  the  capsule  and 
sometimes  blend  with  it,  so  that  there  is  an  intimate  relation  between  the  muscles  and 
their  tendons  and  the  ligaments;  finally,  there  is  a  third  structure  called  the  glenoid 
ligament,  which  is  in  reality  a  fibrocartilage  that  serves  to  deepen  the  glenoid  cavity. 
The  capsular  ligamefit  is  attached  on  one  side  to  the  edge  of  the  glenoid  cavity, 
the  anatomical  neck  of  the  scapula,  and  the  rim  of  the  glenoid  ligament.  On  the 
other  side  it  is  attached  above  or  externally  to  the  anatomical  neck  of  the  humerus  just 
at  the  edge  of  the  articulating  surface,  but  on  the  lower  or  inner  surface  it  is  attached 
some  distance  below  the  articular  surface  (approximately  i  cm. )  and  then  turns 
upward  toward  the  edge  of  the  articular  cartilage.  Thus  a  fracture  through  the  ana- 
tomical neck  might  pass  outside  of  the  joint  above,  and  inside  of  it  below.  The  positions 
assumed  by  the  capsule  in  abduction  and  adduction  are  sho'-i^n  in  Figs.  237  and  238. 


224 


APPLIED    ANATOMY. 


Spine 


Acromion  process 
Glenoid  process 


Capsule 


Joint  cavity 


Long  head  of 
triceps  muscle 


Fig.  237. — Section  of  shoulder- joint,  arm  adducted,  showing  the  position  assumed  by  the  capsule  and  the  points 

of  its  attachment. 


Acromion  process 


Capsule 


Capsule 
Glenoid  process 
Long  head  of  triceps  muscle 


Fig.  238. — Section  of  shoulder-joint,  arm  abducted,  showing  the  attachment  of  the  capsule  and  the  position  u 

assumes  when  the  arm  is  in  this  position. 


THE  SHOULDER-GIRDLE 


225 


The  capsular  ligament,  per  se,  has  not  much  strength.  There  are  two  openings 
in  it — one  is  for  the  long  tendon  of  the  biceps  and  the  other  is  the  opening  of  the 
bursa  beneath  the  subscapularis  muscle.  Sometimes  there  is  a  synovial  extension 
beneath  the  supraspinatus  tendon  and  rarely,  in  old  people,  a  communication  with 
the  subacromial  bursa.  It  is  evident  that  in  case  of  suppuration  within  the  joint  the 
pus  would  tend  to  find  vent  first  through  these  openings. 

The  laxity  of  the  capsule  is  such  that  after  the  muscles  are  removed  the  head 
can  be  drawn  a  considerable  distance  away  from  the  glenoid  cavity.    When  the  mus- 

'  Acromion  process 
Clavicle 


Coracoclavicular  ligaments 


Coraco-acromial  ligament 


Coracoid  process 


Spine 


Glenoid 
ligament 


Long  head  of  biceps 

Glenoid  cavity 


Long  head  of  triceps 


Fig.  239. — View  of  the  left  scapula  and  outer  end  of  the  clavicle  from  in  front,  showing  the  ligaments  pass- 
ing from  the  coracoid  process  to  the  clavicle  and  acromion  process,  the  glenoid  ligament,  and  attachments  of  the 
long  heads  of  the  biceps  and  triceps  muscles. 

cles  are  paralyzed  the  weight  of  the  arm  causes  the  head  to  fall  away  and  a  depres- 
sion is  seen  beneath  the  acromion  process.  The  capsule  is  strengthened  by  two 
definite  and  separate  ligamentous  bands  called  the  coracohumeral  and  the  gleno- 
humeral  ligaments. 

The  coracohumeral  ligament  passes  from  the  root  of  the  coracoid  process  to  the 
anterior  portion  of  the  greater  tuberosity.  It  is  supposed  by  Sutton  to  be  a  regres- 
sion of  the  tendon  of  the  pectoralis  minor  muscle. 

The  glenoJmmeral  liga7nent  is  a  ribbon-like  band  seen  lying  alongside  of  the 

inner  edge  of  the  biceps  tendon  as  it  passes  through  the  interior  of  the  joint.      It 

passes  from  the  root  of  the  coracoid  process  near  the  edge  of  the  glenoid  cavity  to  a 

dimple  in  the  lesser  tuberosity  of  the  humerus.     Sutton  considers  it  a  regression  of 

15 


226 


APPLIED    ANATOMY. 


the  tendon  of  the  subclavius  muscle  and  homologous  with  the  ligamentum  teres  in 
the  hip.  It  is  also  called  the  superior  glenohumeral  ligament,  in  contradistinction 
to  some  bands  on  the  lower  anterior  part  of  the  capsule  which  are  called  by  some 
anatomists  the  middle  and  inferior  glenohumeral  ligaments.  Between  the  superior 
above  and  the  middle  and  inferior  below  is  the  opening  by  which  the  bursa  of  the 
subscapularis  muscle  communicates  with  the  joint. 

The  glenoid  ligament  is  the  wedge-  or  cup-shaped  ring  of  fibrocartilage  which 
deepens  the  glenoid  fossa.  It  is  attached  around  its  edge  to  the  rim  of  the  fossa 
and  at  its  upper  end  receives  the  long  tendon  of  the  biceps,  which  divides  and  blends 
with  it  on  each  side.  At  its  lower  part  when  it  is  attached  to  the  bone  it  blends  with 
the  anterior  edge  of  the  long  tendon  of  the  triceps. 

THE   MUSCLES   OF  THE    REGION   OF   THE   SHOULDER. 

The  shoulder  embraces  two  sets  of  muscles:  one  connects  the  shoulder-girdle 
with  the  trunk  and  the  other  the  humerus  with  the  shoulder-girdle. 

The  inner  end  of  the  clavicle  articulates  with  the  sternum  and  gives  a  bony 
support  to  the   shoulder-girdle   at   this   point.     The   rest   of   the   shoulder-girdle, 


Supraspinatus 
Infraspinatus 


Teres  minor 


Outer  head 


Long  head  of  triceps 


Levator  scapulae 


Rhomboideus 
minor 


Rhomboideus 
major 


^„ _  jHH^B 

of  triceps       /    ,f;i|M/||/|-f ' 


Latissimus  dorsi 


Teres  major 


Fig.  240. — Scapular  muscles. 

comprising  the  remainder  of  the  clavicle  and  all  of  the  scapula  and  bearing  the 
weight  of  the  whole  upper  extremity,  hangs  from  and  is  supported  and  moved  by 
the  muscles  which  pass  from  it  to  the  vertebrae  posteriorly  and  to  the  skull,  hyoid 
bone,  and  ribs  anteriorly. 

Anteriorly  the  clavicle  has  attached  to  its  upper  inner  third  the  clavicular  origin 
of  the  sternomastoid  muscle;  and  on  its  under  surface  is  the  subclavius  muscle,  which 
arises  from  the  cartilage  and  anterior  end  of  the  fir§t  rib.  These  muscles  aid  in  moving 
the  clavicle.  Running  from  the  third,  fourth,  and  fifth  ribs  to  the  coracoid  process  is 
the  pedoralis  minor  rmiscle ;  and  on  the  side  of  the  chest,  passing  to  the  posterior  edge 
of  the  scapula,  is  the  serratus  anterior  {magnus)  muscle.     It  will  be  alluded  to  again. 


THE  SHOULDER-GIRDLE.  227 

Posteriorly  is  the  trapezius  muscle  superficially,  and  beneath  are  the  omohyoid^ 
levator  scapidce,  and  the  two  rhomboid  muscles. 

The  trapezius  arises  from  the  superior  curved  line  of  the  occiput,  the  liga- 
mentum  nuchae,  and  the  spines  of  the  seven  cervical  and  all  of  the  thoracic  vertebrae. 
It  inserts  into  the  upper  surface  of  the  outer  third  of  the  clavicle,  acromion  process, 
and  spine  of  the  scapula  to  near  its  root.  Its  upper  fibres  directly  aid  in  sustaining 
the  weight  of  the  upper  extremity.  It  is  not  infrequently  paralyzed,  and  then  falling 
of  the  shoulder  is  marked.  It  also  tends  to  pull  the  scapula  backward  toward  the 
spine,  and  rotates  it. 

The  levator  scapulae  arises  from  the  transverse  processes  of  the  upper  four 
cervical  vertebrae  and  passes  downward  to  insert  into  the  posterior  edge  of  the 
scapula  between  its  upper  angle  and  the  root  of  the  spine  of  the  scapula. 

The  scapula  is  supported  largely  by  this  muscle;  hence  when  the  trapezius  is 
paralyzed,  as  occurs  in  division  of  its  motor  nerve,  the  spinal  accessory,  this  muscle 
is  utilized  in  counteracting  its  loss. 

The  rhomboid  muscles  arise  from  the  lower  part  of  the  ligamentum  nuchae 
and  the  spines  of  the  seventh  cervical  and  upper  five  thoracic  vertebrae  and  insert 
into  the  posterior  edge  of  the  lower  three-fourths  of  the  scapula. 

The  serratus  anterior  (magnus)  muscle  (Fig.  202),  lies  beneath  the  scapula 
and  arises  from  nine  slips  from  the  outer  surface  of  the  upper  eight  or  nine  ribs; 
the  second  rib  receives  two  slips.  It  passes  backward  and  upward  and  inserts  into 
the  posterior  edge  of  the  scapula  from  its  upper  to  its  lower  angle. 

The  serration  attached  to  the  sixth  rib  is  the  one  that  reaches  farthest  forward 
on  the  side  of  the  chest. 

The  omohyoid  muscle  arises  posteriorly  from  the  upper  border  of  the 
scapula,  just  behind  the  suprascapular  notch,  and  then  runs  upward  and  forward  to 
the  under  surface  of  the  body  of  the  hyoid  bone.  It  is  a  digastric  or  two-bellied 
muscle  and  its  middle  tendon  is  attached  by  a  pulley-like  process  of  the  deep  cervical 
fascia  to  the  first  rib. 

MOVEMENTS  OF  THE  SHOULDER-GIRDLE. 

While  the  muscles  above  enumerated  comprise  all  those  directly  attached  to  the 
shoulder-girdle  and  trunk,  they  are  of  course  assisted  to  some  extent  by  the  muscles 
forming  the  axillary  folds,  viz.,  the  pectoralis  major  anteriorly  and  the  latissimus 
dorsi  and  teres  major  posteriorly. 

The  shoulder-girdle  is  elevated  by  the  upper  fibres  of  the  trapezius,  levator 
scapulae,  rhomboidei,  sternomastoid  (clavicular  origin),  and  omohyoid.  It  is  depressed 
by  the  lower  fibres  of  the  trapezius,  latissimus  dorsi,  lower  fibres  of  the  serratus  ante- 
rior (magnus),  pectoralis  major,  pectoralis  minor,  and  subclavius.  It  is  drawn  forward 
by  the  pectoralis  major,  minor,  subclavius,  serratus  anterior,  omohyoid,  and,  if  the 
arm  is  fixed,  by  the  teres  major  muscles.  It  is  drawn  back  by  the  trapezius,  rhomboidei, 
and  latissimus  dorsi  muscles.  Circumduction  is  effected  by  a  combined  action  of 
various  parts  of  these  muscles. 

SURFACE   ANATOxMY. 

On  observing  the  region  of  the  shoulder  it  is  noticed  that  it  projects  well  out 

from  the  trunk,  so  that  the  arm  hangs  free.      It  has  as  its  framework  three  bones 

the  clavicle  and  scapula  above,  forming  the  shoulder-girdle,  and  the  humerus  below. 
They  radiate  from  the  region  of  the  joint,  the  clavicle  toward  the  front,  the  scapula 
toward  the  back,  and  the  humerus  downward,  forming  the  basis  of  the  shape  of  the 
shoulder,  which  is  modified  by  the  muscles,  fat,  and  skin. 

The  skin  and  fat  bridge  over  and  tend  to  obliterate  the  hollows  and  to  a  less 
extent  obscure  the  prominences.  This  is  more  the  case  as  applied  to  the  muscles 
than  the  bones,  hence  the  bones  form  the  better  landmarks  or  guides. 

Age  and  sex  modify  the  surface  appearances.  In  children  the  bones  are  but 
slightly  developed  and  their  prominences  not  marked.  Fat  is  usually  abundant  and  it' 
is  often  no  easy  task  to  recognize  by  the  sense  of  touch  the  various  anatomical  parts 
and  determine  whether  or  not  they  have  been  injured.     For  this  reason  one  should 


228 


APPLIED    ANATOMY. 


endeavor  to  increase  his  skill  by  taking  advantage  of  every  opportunity  that  offers 
for  examination.  In  the  case  of  women  the  same  thing  usually  exists,  but  to  a  less 
degree.  In  the  somewhat  emaciated  adult  male  the  structures  can  be  recognized  to 
best  advantage. 

The  clavicle  is  subcutaneous,  and  even  in  children  and  fat  people  can  be  felt 
throughout  its  entire  length.  Its  large,  knob-like  inner  extremity  projects  consider- 
ably above  the  upper  edge  of  the  sternum,  which  can  be  felt  at  the  suprasternal  notch. 
Take  particular  notice  of  its  size  and  compare  it  with  the  one  on  the  opposite  side  so 
as  not  to  be  misled  as  to  its  being  diseased  or  luxated.  Follow  the  bone  to  its  outer 
extremity,  which  is  higher  than  the  inner,  more  so  when  lying  down  than  when 
standing.     A  prominent  ridge  marks  its  outer  extremity;  if  it  is  difficult  to  recognize, 


Infraclavicular  triangl 
Outer  end  of  clavicle 


Tip  of  acromion  process 
Greater  tuberosity 

Head  of  humerus 
Deltoid  muscle 


Coracoid  process 

Lesser  tuberosity 
Pectoralis  major 


Fig.  241. — Surface  anatomy  of  the  shoulder. 

as  will  often  be  the  case,  then  continue  directly  outward  to  the  point  of  the  shoulder, 
which  is  formed  by  the  tip  of  the  acromion  process.  Having  recognized  this  point, 
the  end  of  the  clavicle  will  be  found  about  2.5  to  3  cm.  (i  to  i^in. )  directly  inward 
from  it. 

In  the  median  line  above  the  sternum  is  the  suprasternal  notch  with  the  promi- 
nent sternal  origins  of  the  sternomastoid  muscles  on  each  side.  Just  to  the  outer  edge 
of  these  tendons  lie  the  sternoclavicular  joints.  The  one  on  the  right  side  marks  the 
ending  of  the  innominate  artery  and  the  commencement  of  the  right  common  carotid 
and  subclavian.  That  on  the  left  marks  the  left  carotid  with  the  subclavian  directly 
to  its  outer  side  and  a  little  posteriorly. 

If  the  head  is  extended  and  turned  to  the  opposite  side  the  clavicular  origin  of 
the  sternomastoid  is  made  visible.     It  arises  from  the  inner  third  of  the  bone. 


THE  SHOULDER-GIRDLE,  229 

The  inner  two-thirds  of  the  clavicle  is  convex  for\vard.  Above  this  portion  is 
the  subclavian  triangle  in  the  supraclavicular  fossa.  The  older  third  of  the  clavicle 
is  convex  backward  and  from  its  upper  surface  the  trapezius  muscle  can  be  felt  pro- 
ceeding upward.      This  leaves  the  middle  third  of  the  bone  free  from  muscle. 

Under  the  middle  of  the  bone  passes  the  subclavian  artery.  It  curves  upward 
about  2.5  cm.  (i  in.)  above  the  clavicle  to  descend  again  to  the  sternoclavicular  joint. 
The  arch  so  formed  indicates  the  apex  of  the  lung  because  the  subcla\'ian  artery- 
rests  on  the  pleura.  The  internal  jugular  vein  passes  down  opposite  the  interval 
between  the  sternal  and  clavicular  heads  of  the  sternomastoid  muscle. 

Just  above  the  clavicle,  a  little  internal  to  its  middle,  and  behind  the  clavicular 
origin  of  the  sternomastoid  muscle  is  seen  the  external  jugular  vein.  It  terminates 
in  the  subclavian  vein,  which  lies  to  the  inner  (anterior)  side  of  the  artery.  To  the 
outer  side  of  the  artery  the  cords  of  the  brachial  plexus  pass  upward  and  inward. 
They  become  prominent  in  emaciated  subjects  when  the  head  is  turned  forcibly 
toward  the  opposite  side.  The  posterior  belly  of  the  omohyoid  muscle  varies  much 
in  its  position,  sometimes  it  lies  behind  the  clavicle,  at  others  two  or  three  centimetres 
above  it. 

Immediately  below  the  clavicle  is  the  infraclavicular  fossa.  At  its  inner  extremity 
can  be  felt  the  first  rib.  As  it  is  exceedingly  easy  to  mistake  the  ribs,  it  is  best,  in 
counting  them,  to  locate  the  second  rib  by  recognizing  the  angle  of  the  sternum, 
(angle  of  Ludwig)  to  which  it  is  opposite,  on  the  surface  of  the  sternum  about  5  cm. 
(2  in. )  below  its  upper  edge.  Attached  to  the  lower  edge  of  the  iiiner  half  of  the 
clavicle  is  the  pectoralis  major  muscle  and  to  the  oiiter  third  the  deltoid  muscle. 

This  leaves  one  sixth  of  the  lower  edge  of  the  clavicle  free  from  muscular  attach- 
ments. This  forms  the  base  of  the  subclavicular  triangle  and  its  two  sides  are  formed 
by  the  adjacent  edges  of  the  pectoralis  major  and  deltoid  muscles.  Beneath  this 
triangle  runs  the  first  portion  of  the  axillary  artery  with  the  vein  to  its  inner  side 
and  the  cords  of  the  brachial  plexus  to  its  outer  side.  Deep  pressure  at  this  point 
can  compress  it  against  the  second  rib,  but  not  so  effectively  as  above  the  clavicle. 

Just  to  the  outer  side  of  the  junction  of  the  middle  and  outer  thirds  of  the 
clavicle,  in  front  of  the  deepest  part  of  the  concavity  of  the  clavicle  and  about  2.5  cm. 
( I  in.  )  below  it,  is  the  coracoid  process.  It  is  better  felt  by  pressing  the  fingers  flat 
on  the  surface  than  by  digging  them  in.  It  is  somewhat  obscured  by  the  edge  of 
the  deltoid  muscle,  which  covers  it.  Running  from  the  coracoid  to  the  acromion 
process  is  the  sharp  edge  of  the  coraco-acromial  ligament.  An  incision  midway 
between  the  two  processes  would  open  the  joint  and  strike  the  long  biceps  tendon 
as  it  winds  over  the  head  of  the  humerus  to  reach  the  upper  edge  of  the  glenoid 
cavity. 

Beneath  the  acromion  process  is  felt  the  greater  tuberosity  of  the  humerus.  If 
the  arm  is  placed  alongside  of  the  body  with  the  palm  facing  forward,  a  distinct  groove 
can  be  felt  to  the  inner  side  of  the  acromion  process  passing  downward  on  a  line  with 
the  middle  of  the  arm.  It  is  the  bicipital  groove  for  the  long  tendon  of  the  biceps 
muscle.  The  bony  process  of  the  humerus  to  its  outer  side  is  the  greater  tuber- 
osity and  that  to  its  inner  side,  between  it  and  the  coracoid  process,  on  a  slightly 
lower  level,  is  the  lesser  tuberosity.  It  will  be  noted  that  the  greater  tuberosity  pro- 
jects beyond  the  acromion  process  and  forms  the  prominence  of  the  shoulder.  On 
rotating  the  arm  the  tuberosities  can  be  distinctly  felt  moving  under  the  deltoid  muscle. 

Following  the  acromion  process  around  toward  the  back  it  turns  abruptly  where 
it  joins  the  spine  of  the  scapula,  forming  a  distinct  angle.  This  angle  is  quite  prom- 
inent, can  be  readily  seen  and  felt,  and  can  be  used  as  a  landmark  for  measuring  the 
length  of  the  humerus.  If  the  spine  of  the  scapula  is  followed  still  farther  it  ends 
in  its  root  at  the  posterior  border  of  the  bone  opposite  the  upper  edge  of  the  fourth 
rib  and  third  thoracic  spine.  This  marks  the  upper  extremity  of  the  fissure  of  the 
lung;  with  the  arm  to  the  side,  the  lower  angle  of  the  scapula  lies  over  the  seventh 
interspace. 

Axilla. — On  raising  the  arm  directly  out  from  the  body  the  armpit  and  axillary 
folds  become  visible.  The  rounded  edge  of  the  anterior  axillary  fold  is  formed  by 
the  pectoralis  major  muscle.  It  follows  the  fifth  rib  and  its  upper  end  merges  with 
the  lower  edge  of  the  deltoid  muscle. 


230  APPLIED    ANATOMY. 

If  firm  pressure  is  made  along  the  inner  or  lower  edge  of  the  outer  extremity 
of  the  anterior  axillary  fold  the  upper  end  of  the  biceps  muscle  can  be  felt,  and  lying 
along  with  it,  to  its  inner  side,  is  the  swell  formed  by  the  coracobrachialis  muscle. 

Along  the  inner  edge  of  the  coracobrachialis  muscle  lies  the  axillary  artery  with 
its  vein  to  the  inner  side.  This  is  a  little  anterior  to  the  middle  of  the  axilla.  The 
artery  can  be  felt  pulsating  along  the  inner  edge  of  the  coracobrachialis  and  can  be  com- 
pressed by  pressure  made  in  an  outward  and  backward  direction  against  the  humerus. 
The  line  of  the  axillary  artery  is  from  the  middle  of  the  clavicle  down  along  the  inner 
edge  of  the  coracobrachialis  muscle,  which  will  be  anterior  to  the  middle  of  the  axilla. 

The  posterior  fold  of  the  axilla  is  formed  by  the  latissimus  dorsi  and  teres  major 
muscles.  By  deep  pressure  in  the  axilla,  posterior  to  the  vessels,  the  arm  being 
abducted,  the  rounded  head  of  the  humerus  can  be  felt. 

When  the  arm  is  brought  more  to  the  side  the  tissues  of  the  axilla  relax  and  any 
enlarged  lymph-nodes  present  may  be  recognized.     When  normal  they  cannot  be  felt. 

Winding  around  the  surgical  neck  of  the  humerus  from  behind  forward  under 
the  deltoid  muscle  about  at  the  junction  of  its  upper  and  middle  thirds  is  the  pos- 


Biceps 
Deltoid 


Pectoralis  major 


—  Coracobrachialis 

Groove  for  axillary 
vessels  and  nerves 


Long  head  of  triceps  muscle 

•Teres  major  and  latissimus  dorsi  muscles 


Fig.  242. — Surface  anatomy  of  the  axilla. 

terior  circumflex  artery  and  circumflex  nerve.  Hence  a  blow  at  this  point  may  injure 
the  nerve  and  cause  paralysis  of  the  deltoid  muscle.  The  line  of  fracture  of  the 
surgical  neck  of  the  humerus  would  also  lie  at  this  point. 

DISLOCATIONS  OF  THE  CLAVICLE. 

Dislocation  of  the  Sternal  End  of  the  Clavicle. — The  sternal  end  of  the 
clavicle  is  most  commonly  dislocated  forward.  Other  dislocations,  which  may  be 
upward  or  backward,  are  very  rare.  The  range  of  movement  of  the  clavicle  approxi- 
mates 60  degrees. 

The  bone  is  lowest  when  the  elbow  is  brought  forward  across  the  front  of  the  body 
and  highest  when  the  arm  is  raised  and  placed  behind  the  neck.  The  luxation  is  pro- 
duced by  the  shoulder  being  violently  depressed  and  pushed  backward,  as  in  falling 
on  it;  in  some  cases  an  inward  thrust  may  be  added.  As  the  clavicle  descends  its  under 
surface  comes  into  contact  with  the  first  rib,  which  acts  as  a  fulcrum,  and  the  inner 
extremity  is  lifted  upward  and  forward,  rupturing  the  sternoclavicular  ligaments.  The 
rhomboid  ligament  remaining  intact  prevents  a  wider  displacement  of  the  bone. 


THE  SHOULDER-GIRDLE. 


231 


As  regards  treatment,  to  reduce  the  luxation  the  shoulder  should  be  elevated 
and  drawn  outward  and  backward.  While  pressure  is  made  on  the  protruding  bone 
the  arm  is  used  as  a  lever  and  the  bone  tilted  into  place.  Usually  reduction  can  be 
readily  accomplished,  but  most  people  have  found  it  difficult  to  retain  the  parts  in 


Sternum 


Clavicle 


Subclavius  muScle 


Costoclavicular  or 
rhomboid  ligament 


First  rib 

Second  rib  , 

Fig.  243. — Dislocation  of  the  sternal  end  of  the  clavicle  upward  and  forward,  showing  how  the  first  rib  acts  as  a 

fulcrum  and  the  clavicle  as  a  lever. 

place.  The  only  sure  way  of  doing  so  is  to  keep  the  patient  in  bed  on  his  back. 
Stimson,  following  Velpeau  and  Malgaigne,  advises  the  application  of  an  anterior 
figure  eight  bandage  of  plaster  of  Paris;  Hamilton  says  deformity  remains  after  any 
method  of  treatment,  but  that  function 
will  be  but  little  impaired. 

In  upward  dislocations  the  case  of 
R.  W.  Smith  has  shown  that  the  end  of 
the  bone  passes  behind  the  sternal  origin 
of  the  sternomastoid  muscle. 

In  backward  dislocations  pressure 
on  the  trachea  and  oesophagus  have 
caused  difficulty  in  breathing  and  swal- 
lowing; cyanosis  due  to  pressure  on  the 
internal  jugular  vein  has  been  observed 
in  one  case.  When  one  recalls  the 
function  of  the  clavicle  in  keeping  the 
shoulder  out  from  the  body,  it  is  readily 
seen  that  when  the  security  of  its  inner 
attachment  has  once  been  destroyed  dis- 
placement is  favored  by  the  weight  of 
the  upper  extremity  as  well  as  by  the 
action  of  all  the  muscles  which  pass 
from  the  head,  neck,  and  trunk  to  the 
shoulder-girdle  and  humerus. 

In  these  dislocations  of  the  sternal 
end  of  the  clavicle  the  fibrocartilaginous 
disk  of  the  joint  sometimes  is  carried  out  with  the  clavicle  and  sometimes  remains 
attached  to  the  sternum,  more  often  it  follows  the  clavicle. 

Dislocation  of  the  Acromial  End  of  the  Clavicle. - 
the  clavicle  may  be  dislocated  either  upward  or  downward, 
tions  are  upward. 

The  displacement  is  usually  produced  by  direct  violence 
back  of  the  shoulder  driving  the  acromion  down  and  inward. 


Fig.  244. — Luxation  of  the  outer  end  of  the  clavicle 
upward,  showing  the  coracoid  process  acting  as  a  fulcrum. 
As  the  outer  end  of  the  clavicle  rises,  the  lower  angle  of  the 
scapula  is  carried  toward  the  median  line  and  the  acromion 
process  is  depressed  and  torn  loose  from  the  clavicle  above. 


—The  acromial  end  of 
Nearly  all  the  disloca- 


a  blow  on  the  top  or 
The  clavicle  not  only 


232  APPLIED    ANATOMY. 

rises  but  also  goes  backward,  or  the  scapula  comes  forward,  so  that  the  end  of  the 
clavicle  may  rest  on  the  acromion  process.  In  this  dislocation  the  base  of  the  cora- 
coid  process,  on  which  the  clavicle  rests  and  to  which  it  is  bound  by  the  conoid  and 
trapezoid  ligaments,  acts  as  a  fulcrum.  The  scapula  rotates  on  an  anteroposterior 
axis,  passing  through  the  base  of  the  coracoid  process,  and  as  the  inner  portion  of 
the  bone  rises,  its  outer  portion, — that  is,  the  acromion  process, — descends  and  is  torn 
from  the  outer  end  of  the  clavicle. 

The  deformity  produced  by  the  upwardly  projecting  end  of  the  clavicle  is  typical. 
The  luxation  may  be  complete  or  incomplete.  When  incomplete  the  injury  is  con- 
fined to  the  acromioclavicular  joint;  when  complete  the  conoid  and  trapezoid  ligaments 
are  partially  or  wholly  ruptured. 

The  joint  usually  possesses  a  poorly  developed  fibrocartilage  and  inclines  upward 
and  outward  so  that  the  inclination  favors  the  rise  of  the  clavicle.  When  the  conoid 
and  trapezoid  ligaments  are  not  ruptured  they  serve  as  the  axis  on  which  the  scapula 
rotates  forward  so  that  the  outer  end  of  the  clavicle  slips  backward  on  the  acromion 
process.  This  led  Hamilton  to  describe  these  luxations  as  backward  luxations.  In 
rare  instances  the  end  of  the  clavicle  seems  to  be  displaced  posteriorly  without 
rising  above  its  normal  level.  We  reported  one  such  case  in  the  Annals  of 
Surgery  several  years  ago.  Reduction  of  the  displacement  is  easily  effected,  but 
the  same  difficulty  in  keeping  the  bone  in  place  has  been  experienced  in  this  disloca- 
tion as  in  dislocations  of  the  inner  extremity.  Bandages  going  over  the  shoulder 
and  down  the  arm  and  under  the  elbow  are  commonly  employed.  The  only  sure 
way  of  keeping  the  clavicle  in  its  proper  position  is  to  operate  and  fasten  it  to  the 
acromion  with  wire  or  chromicised  catgut.  When  the  patient  is  put  in  bed  the  bones 
are  readily  replaced. 

Downzvard  dislocation  though  rare  does  seem  to  have  sometimes  occurred. 
From  the  fact  of  the  under  surface  of  the  clavicle  resting  almost  or  quite  on  the 
coracoid  process  it  is  difficult  to  see  how  it  is  possible  for  this  injury  to  take  place. 
It  must  take  place  while  the  scapula  is  violently  twisted  on  the  clavicle.  The 
displacement  is  readily  reduced  and  shows  but  little  tendency  to  recurrence. 

DISLOCATIONS  OF  THE  SHOULDER. 

The  dislocations  of  the  shoulder  are  to  be  studied  from  the  anatomical  and  not 
from  the  clinical  standpoint.  A  knowledge  of  the  anatomical  construction  of  the 
various  parts  involved  is  to  be  applied  to  the  explanation  and  elucidation  of  the 
methods  of  production,  the  signs  and  symptoms  observed,  and  the  procedures  neces- 
sary for  reduction. 

Classification. — For  our  purpose  there  are  two  forms  of  dislocations  of  the 
shoulder — anterior  and  posterior.  These  two  forms  are  entirely  different  and  must 
be  studied  separately. 

Anterior  Dislocation. — An  anterior  luxation  is  one  in  which  the  head  of  the 
humerus  is  either  on  or  anterior  to  the  long  head  of  the  triceps  muscle  at  the  lower 
edge  of  the  glenoid  cavity. 

Posterior  Dislocation. — A  posterior  luxation  is  one  in  which  the  head  goes  poste- 
rior to  the  glenoid  cavity  and  usually  rests  beneath  the  spinous  process  of  the  scapula, 
hence  this  is  called  subspinous  dislocation. 

When  the  head  is  luxated  anteriorly  it  may  pass  so  far  inward  as  to  rest  between 
the  coracoid  process  and  the  clavicle;  hence  this  form  is  called  subclavicular. 

When  the  head  does  not  pass  so  far  inward,  but  rests  on  the  anterior  edge  of  the 
glenoid  cavity  below  the  coracoid  process,  it  is  called  a  subcoracoid  luxation. 

When  it  rests  on  the  anterior  and  lower  edge  of  the  glenoid  cavity,  sometimes 
on  the  long  head  of  the  triceps  muscle  or  just  anterior  to  it,  it  is  called  a  subglenoid 
luxation. 

ANTERIOR  DISLOCATION  OF  THE  SHOULDER. 

The  head  of  the  bone  almost  always  comes  out  through  the  anterior  portion  of 
the  capsule  and  slips  beneath  the  coracoid  process.  From  this  point  it  may  shift  its 
position  either  a  little  farther  inward,  when  it  is  called  a  subclavicular  luxation,  or  a 
little  farther  downward  and  outward,  when  it  receives  the  name  of  subglenoid. 


THE  SHOULDER-GIRDLE. 


233 


As  a  matter  of  fact  the  head  usually  comes  to  rest  beneath  the  coracoid  process 
and  permanent  fixation  of  the  bone  either  in  the  subclavicular  or  subglenoid  positions 
is  very  rare.  As  the  symptoms  and  methods  of  treatment  are  identical  they  will  all 
be  included  under  the  one  head  of  subcoracoid  luxations.  What  are  commonly 
regarded  as  subglenoid  luxations  are  really  subcoracoid. 

Method  of  Production  of  Anterior  Luxations.  — Anterior  luxations  are  produced 
by  the  arm  being  hyperabducted,  rotated  outward,  and  the  head  of  the  bone  pushed 
or  pulled  in  toward  the  body.  Rotation  may  not  be  essential,  but  it  is  largely 
responsible  for  the  wide  detachment  of  the  capsule  which  is  present  in  these  injuries. 
When  the  arm  is  raised  from  the  body  much  beyond  a  right  angle  the  greater 
tuberosity  strikes  the  acromion  process.  If  the  hyperabduction  is  continued  the  acro- 
mion process  acts  as  a  fulcrum  and  the  head  of  the  bone  is  lifted  from  its  socket, 
tearing  away  the  capsule  of  the  joint  in  front  of  and  below  the  glenoid  cavity. 


Fig.  245. — Dislocation  of  the  shoulder;  action  of  the  bones;  by  extreme  abduction  of  the  humerus  over  the 
acromion  process  as  a  fulcrum  the  head  is  levered  out  of  the  socket. 


If  now  the  arm  rotates,  the  capsule  is  still  farther  detached  and  if  the  force  con- 
tinues to  act,  as  in  those  cases  in  which  a  person  is  thrown  forward  and  alights  on 
the  outstretched  arm,  or  if  the  axillary  muscles  contract,  the  head  is  thrust  from  its 
socket.  After  once  leaving  the  socket,  subsequent  movements  may  cause  the  head 
to  assume  various  positions  around  the  glenoid  cavity;  as  a  matter  of  fact  it  is  almost 
always  below  the  coracoid  process. 

Parts  Injured. — When  the  luxation  occurs  the  arm  is  hyperabducted  and,  owing 
to  the  acromion  process  being  somewhat  posterior  to  the  glenoid  cavity,  pointing 
backward,  this  places  it  up  almost  or  quite  alongside  of  the  head.  The  force  which 
thrusts  the  bone  out  acts  downward  toward  the  axilla  and  inward  toward  the  body. 
The  posterior  border  of  the  scapula  is  prevented  from  descending  by  the  levator 
scapuke  and  rhomboid  muscles,  hence  it  is  the  joint  which  descends  and  tears  loose 
the  capsule  already  stretched  tightly  over  the  head  of  the  humerus. 

This  is  the  reason  why  the  lower  portion  of  the  capsule  is  torn;  it  is  the  longi- 


234 


APPLIED    ANATOMY. 


tudinally  acting  force  that  does  it.  When  the  transverse  force  acts  it  is  expended  on  the 
anterior  portion  of  the  joint  because  the  joint  is  at  the  anterior  portion  of  the  scapula. 
Posterior  to  the  joint  the  scapula  rests  on  the  chest,  so  it  is  its  anterior  portion  which 
is  forced  inward,  thus  rupturing  the  capsule  at  this  point.  The  fulcrum,  or  acromion 
process,  is  also  posterior  to  the  midline  of  the  joint. 

By  a  combination  of  these  two  forces  (longitudinal  and  transverse)  the  capsule 
is  ruptured  at  its  lower  and  especially  its  anterior  portion.  Its  tearing  is  favored  by 
a  twisting  or  external  rotation  of  the  humerus.  The  attachment  of  the  capsule  is 
torn  from  the  rim  of  the  glenoid  cavity,  not  from  the  humerus,  and  a  fragment  of  the 
bony  rim  frequently  comes  with  it.      The  opening  is  large  and  embraces  nearly  or 


Prominent  acromion 
process 


Coracoid  procesi 


Tense  fibres  of 
the  deltoid 

Prominence  formed 

by  the  head  of 

the  humerus 


Fig.  246. — Surface  view:  subcoracoid  dislocation  of  the  humerus,  showing  the  elevation  of  the  shoulder, 
abduction  of  the  arm,  prominence  of  the  displaced  head  below  the  coracoid  process,  flattening  of  the  shoulder, 
and  tense  fibres  of  the  deltoid  muscle. 

quite  half  the  circumference  of  the  joint.  It  is  limited  above  by  the  coracoid  process. 
The  coracohumeral  and  superior  glenohumeral  ligaments  lying  in  front  of  the  long 
tendon  of  the  biceps  also  limit  the  tear  upwards.  If  the  tear  does  not  extend  so  high 
it  is  because  the  subscapularis  muscle,  instead  of  being  torn,  is  wedged  in  between 
the  head  and  the  coracoid  process.  Below,  the  tear  is  limited  by  the  insertion  of  the 
long  head  of  the  triceps.  As  the  head  luxates  it  cannot  pierce  the  triceps  tendon, 
so  it  slips  behind  it  in  a  posterior  luxation  and  in  front  of  it  in  an  anterior  luxation. 
The  supraspinatus,  infraspinatus,  and  teres  minor  muscles  are  all  posterior;  they 
blend  more  or  less  with  the  capsule  and  as  the  head  luxates  they  are  stretched  with 
it  over  the  glenoid  cavity. 

The  long  tendon  of  the  biceps,  while  it  may  sometimes  be  torn  loose  from  the 
bicipital  groove  after  rupture  of  the  transverse  ligament,  is  usually  so  loose  that  it 


THE  SHOULDER-GIRDLE. 


235 


follows  the  head  without  being  detached  from  its  connections.     The  subscapularis 
muscle  not  infrequently  has  its  lower  edge  torn. 

The  brachial  plexus  and  blood-vessels  are  pushed  inward  by  the  head,  but  when 
the  arm  is  abducted  they  are  stretched  over  it,  running  close  to  the  coracoid  process. 


Fig.  247. — Subcoracoid  dislocation  of  the  humerus,  showing  the  position  of  the  bones  in  relation  to  each  other  and 

to  the  soft  parts. 

As  the  circumflex  nerve  winds  around  the  surgical  neck  of  the  humerus,  it  may  be 
ruptured  or  tightly  stretched  over  the  head  of  the  bone. 

Hyperabduction  stretches  the  vessels  and  nerves  so  forcibly  over  the  head  just 
prior  to  its  leaving  the  socket  as  sometimes  to  produce  serious  injury  to  them. 


Signs  and  Symptoms. 

There  is  (i)  at  first  elevation  then  lowering  of  the  shoulder,  (2)  flattening  of  the 
deltoid  muscle,  (3)  projection  of  the  elbow  away  from  the  side.  (4)  The  normal 
hollow  below  the  outer  third  of  the  clavicle  is  filled  up ;  the  head,  covered  by  the  deltoid, 
may  sometimes  even  make  a  rounded  prominence  at  this  point  which  can  frequently  be 
felt.  (5)  If  the  elbow  is  raised  and  the  hand  placed  on  the  opposite  shoulder  and  held 
there  the  elbow  cannot  be  brought  flat  on  the  chest  (Dugas's  sign),  (6)  with  the 


236  APPLIED    ANATOMY. 

arm  to  the  side  the  distance  from  the  acromion  process  to  the  external  condyle  is 
increased,  with  the  arm  abducted  to  a  right-angle,  the  same  distance  is  decreased  as 
compared  with  the  previous  position  as  well  as  when  compared  with  the  arm  of  the 
opposite  side  (see  Fig.  248). 

1.  Lowering  the  shoulder  obviates  pain  by  relaxing  the  deltoid  and  preventing 
it  from  forcing  the  head  upward  in  its  displaced  position. 

2.  Flattening  of  the  shoulder  is  due  to  the  head  and  tuberosities  being  displaced 
inward,  thus  leaving  the  socket  empty.  A  marked  depression  can  be  felt  with  the 
fingers  below  the  prominent  acromion  process. 

3.  Projection  of  the  elbow  from  the  side  is  due  to  tension  of  the  deltoid  muscle 
because  the  head  is  lower  than  normal.  In  its  natural  position  the  top  of  the  head  is 
about  level  with  the  coracoid  process;  when  luxated  it  is  below  it. 

4.  The  normal  hollow  below  the  outer  third  of  the  clavicle  is  lost  because  here  i.s 
where  the  head  lies.      It  may  form  a  distinct  prominence  and  when  the  arm  is  rotated 


Fig.  248. — Subcoracoid  dislocation  of  the  shoulder.  The  head  of  the  humerus  has  slipped  off  its  pedestal  or 
shoulder-girdle  onto  the  side  of  the  thorax.  This  shows  how  the  arm  is  shortened  and  why  it  is  necessary  to- 
make  traction  in  order  to  replace  the  humerus  up  again  on  the  shoulder-girdle. 

if  the  surgeon  lays  his  hand  at  this  point  the  tuberosities  can  be  felt  to  rotate  beneath. 
If  the  arm  is  abducted  the  head  can  usually  be  felt  in  the  axilla,  where  it  may  even 
form  a  prominence. 

5.  In  Dugas's  test  the  elbow  cannot  be  brought  to  the  chest  because  the  outer 
end  of  the  humerus  is  held  close  to  the  chest-wall.  On  account  of  the  thorax  being 
rounded  like  a  barrel  it  is  necessary  for  the  outer  end  of  the  bone  to  rise  as  the  inner 
end  falls. 

6.  The  reason  for  the  difference  in  measurements  when  the  shoulder  is  luxated 
is  readily  seen  by  the  fact  that  the  head  is  displaced  downward  and  inward  as  shown 
in  the  accompanying  figure. 

Treatment. 

Reduction  of  an  anterior  luxation  of  the  shoulder  can  be  accomplished  in  two 
ways,  viz. ,  the  direct,  in  which  the  head  is  pulled  or  pushed  back  into  the  socket, 
and  the  indirect,  in  which  it  is  levered  back. 

Direct  Method. — This  consists  in  first  placing  the  arm  in  approximately  the 
position  it  occupied  when  luxated  (abduction)  and  then  pulling  or  pushing  the 
head  toward  and  into  the  socket  while  the  arm  is  rotated  to  relax  the  capsule  and 
allow  the  head  to  enter.  The  usual  obstacle  to  reduction  of  a  recent  luxation  is 
muscular  contraction.  The  main  muscles  acting  are  the  deltoid,  pectoralis  major, 
latissimus  dorsi,  and  teres  major.  To  effect  reduction  the  action  of  these  muscles 
must  either  be  held  in  abeyance  or  overcome  by  force.  This  may  be  accomplished 
in  several  ways,  viz. ,  by  the  use  of  general  anaesthesia,  by  such  gentle  manipulations 


THE  SHOULDER-GIRDLE. 


237 


as  will  not  incite  the  muscles  to  contraction,  by  a  quick  movement  accomplishing  the 
object  before  the  muscles  are  able  to  contract,  or,  finally,  by  overcoming  the  muscular 
action  bv  steady  continuous  traction.  General  anaesthesia  is  the  surest  way  of  obvi- 
ating muscular  contraction. 

The  question  of  muscular  contraction  having  been  solved  by  one  or  more  of  these 
expedients  the  actual  replacement  is  to  be  accomplished  by  dragging  or  pushing  the 
head  back  over  the  route  it  took  in  coming  out.  The  opening  in  the  capsule  is 
below  and  anterior,  therefore  the  arm  is  to  be  strongly  abducted,  and  traction  made 
upward  and  backward.  This  drags  the  head  upward  and  backward  over  the  rim  of 
the  glenoid  cavity  into  its  socket.      If  it  does  not  enter  readily  it  is  because  of  tension 


Coracoid  process 


Acromion  process 

Long  head  of  biceps 
Supraspinatus 

Infraspinatus 
Teres  minor 


Deltoid  detached 
from  the  clavicle 
and  turned  back 

Long  head 
of  triceps 


Coracobrachialis 

and  short  head 

of  biceps 


Pectoralis  major 


Pectoralis  minor 


Displaced  head 
of  humerus 


Subscapularis 


Fig.  249. — Subcoracoid  dislocation  of  the  shoulder.     Dissection  showing  the  relation  of  the  muscles  to  the  dis- 
placed humerus. 

of  the  untorn  part  of  the  capsule;  this  is  to  be  remedied  by  gently  rotating  the  arm, 
when  the  proper  position  will  be  revealed  by  the  slipping  of  the  head  into  place.  Rota- 
tion in  either  direction  beyond  the  proper  point  narrows  the  tear  in  the  capsule  and 
keeps  the  head  from  entering.  Traction  is  necessary  in  order  to  replace  the  head  of 
the  humerus  on  its  pedestal  or  shoulder-girdle  from  which  it  has  fallen  onto  the  side 
of  the  chest  (see  Figs.  248  and  250). 

If  it  is  desired  to  tire  the  muscles  out,  the  plan  of  Stimson  is  best.  Place  the 
patient  in  a  canvas  hammock  and  allow  the  arm  to  hang  downward  through  a  hole 
in  the  canvas.      Fasten  a  ten-pound  weight  to  the  wrist  and  inside  of  six  minutes  the 


238 


APPLIED    ANATOMY. 


weight  will  have  dragged  the  head  of  the  humerus  into  place.  This  same  object  can 
be  carried  out,  but  not  so  well,  by  having  the  patient  lie  on  the  floor  and  pulling  the 
arm  directly  upward  by  means  of  a  rope  and  pulley.  Here  the  weight  of  the  body 
acts  as  the  counter  force. 

Other  means,  such  as  the  heel  in  the  axilla,  etc.,  may  be  found  described  in 
works  on  surgery,  but  it  is  to  be  remembered  that  the  objects  to  be  sought  are  (i)  to 
overcome  the  action  of  the  deltoid  by  abducting  the  arm,  (2)  to  overcome  the  axillary 
muscles — pectoralis  major,  latissimus  dorsi,  and  teres  major — by  traction,  and  (3)  to 
loosen  the  capsule  and  open  the  tear  to  its  widest  extent  by  rotation  while  the  head 
is  pushed  with  the  hand  toward  and  over  the  lower  and  anterior  edge  of  the  socket. 


Fig.  250. — Diagram  to  show  how  rotation  influences  the  size  of  the  rent  in  the  capsule.  The  square  rep- 
resents the  rent  in  the  capsule  and  the  circle  the  head  of  the  humerus.  If  the  humerus  is  rotated  too  much  in 
the  direction  of  the  arrows,  either  to  the  right  or  left,  the  opening  in  the  capsule  is  so  narrowed  as  to  obstruct 
the  passage  of  the  head. 

Indirect  Method. — The  indirect  or  lever  method  has  been  best  systematized 
by  Kocher  of  Berne,  although  Henry  H.  Smith,  a  former  professor  of  surgery  in  the 
University  of  Pennsylvania,  taught  a  similar  method  previously  (see  H.  H.  Smith's 
"Surgery,"  11  vols.,  also  Packard's  "  Minor  Surgery,"  p.  204,  and  Ashhurst's  "Sur- 
gery," 2d  Ed.,  Phila.  1878,  p.  284).  Kocher's  method  is  as  follows:  First  Step. 
— Flex  the  forearm  until  it  forms  a  right  angle  with  the  arm,  then,  with  the  elbow 
touching  the  side  of  the  body,  rotate  the  arm  outward  90  degrees  until  the  forearm 
points  directly  outward  (Fig.  251).  This  causes  the  head  of  the  bone  to  rotate  out- 
ward and  leave  the  side  of  the  chest  to  take  a  position  close  to  the  glenoid  cavity. 
Second  Step. — The  arm  being  held  in  this  position,  the  elbow  is  raised  forward  until 


Fig.  251. — Kocher's  method  of  reducing  dislocation  of  the  shoulder:  First  step — Flex  the  forearm  at  a  right 
angle  to  the  arm;  bring  the  humerus  alongside  the  chest,  the  elbow  nearly  touching  the  side,  and  rotate  outward 
as  far  as  the  arm  will  go  without  undue  force. 

it  forms  a  right  angle  or  a  little  more  with  the  long  axis  of  the  body.  This  relaxes 
the  coracobrachialis  muscle,  releases  the  lesser  tuberosity,  which  may  be  caught  against 
it,  and  allows  the  head  to  pass  outward  and  ascend  from  its  low  position  up  into  the 
glenoid  cavity  (Fig.  252).  Third  Step. — Carry  the  arm  obliquely  inward,  place 
the  hand  on  the  opposite  shoulder  and  bring  the  elbow  down  to  the  surface  of  the 
chest,  the  humerus  pointing  diagonally  downward  and  inward  as  in  the  Velpeau 
position  for  fractured  clavicle  (Fig.  253). 

The  mechanism,  as  readily  demonstrated  on  the  cadaver,  is  as  follows:  The 
head  lies  to  the  inner  side  of  the  glenoid  cavity  with  the  tense  posterior  portion  of 
the  capsule  passing  backward.  When  external  rotation  is  made  the  capsule  is  wound 
around  the  head  and  upper  portion  of  the  neck  and  the  head  moves  out.  In  some 
instances  the  head  will  not  only  move  out  but  will  likewise  move  up  and  be  drawn  at 


THE  SHOULDER-GIRDLE^ 


239 


once  into  place.  Bringing  the  arm  forward  and  upward  relaxes  the  coracobrachialis 
muscle,  while  bringing  it  across  the  chest  in  the  last  step  assists  the  head  over  the 
rim  of  the  glenoid  ca\ity  and  restores  the  member  to  its  normal  position.  Prof. 
H.  H.  Smith  brought  the  elbow  forward  before  making  the  external  rotation  instead 
of  after,  as  did  Kocher.  This  is  probably  the  better  way  because  persistence  in  rotat- 
ing outward  when  the  lesser  tuberosity  is  caught  beneath  the  tense  coracobrachialis 
muscle  is  one  cause  of  the  frequent  fracture  of  the  humerus  in  attempting  to  carry 


Fig.  252. — Kocher's  method  of  reducing  dislocation  of  the  shoulder:  Second  step — Keeping  the  arm  in  external 
rotation,  raise  the  elbow  until  the  humerus  reaches  the  vertical  line  or  a  little  beyond. 

out  Kocher's  method  ;  another  cause  is  the  fixation  due  to  strong  muscular  con- 
traction or  to  jamming  of  the  head  between  the  scapula  and  side  of  the  chest. 

This  method  can  be  used  without  anaesthesia,  but  it  is  at  times  exceedingly  pain- 
ful and  savors  of  cruelty.  It  is  particularly  applicable  for  old  and  severe  cases.  It 
depends  for  its  efficiency  on  the  integrity  of  the  posterior  portion  of  the  capsule,  if  this 
has  been  torn  loose  the  method  fails  and  the  head  simply  rotates  in  situ.  If  this 
latter  is  the  case,  reduction  can  readily  be  effected  by  direct  traction  and  manipulation. 


Fig.  253. — Kocher's  method  of  reducing  dislocation  of  the  shoulder:  Third  (final)  step — Rotate  the  arm  inward 
and  place  the  hand  on  the  opposite  shoulder  bringing  the  elbow  down  on  the  anterior  surface  of  the  chest. 


POSTERIOR  DISLOCATIONS  OF  THE  SHOULDER. 

Posterior  dislocations  are  always  beneath  some  portion  of  the  spine  of  the  scapula, 
hence  they  have  been  called  snbspiyioics.  When  the  head  lies  anteriorly  under  the 
posterior  portion  of  the  acromion  process  they  have  been  called  subacromial. 

Posterior  luxations  are  rare.  They  occur  either  when  the  arm  is  abducted  with 
strong  internal  rotation  or  by  direct  violence,  such  as  a  blow  on  the  anterior  portion  of 
the  shoulder,  which  forces  the  head  out  of  its  socket  backward.  The  posterior  portion 
of  the  capsule  is  torn  and  the  head  lies  posterior  to  the  glenoid  cavitv  with  its  anatomi- 
cal neck  res.ting  on  the  rim  and  the  lesser  tuberosity  in  the  glenoid  fossa.  The  arm 
is  inverted  and  abduction  and  rotation  impaired.  The  capsule  is  ruptured  by  internal 
rotation  while  the  arm  is  in  a  position  of  abduction,  and  then  a  push  sends  the  head  pos- 
teriorly.    We  have  seen  it  as  a  congenital  affection  resulting  from  injury  in  childbirth. 


240 


APPLIED    ANATOMY. 


Lesser  tuberosity  of  the  humerus 
Relaxed  tendon  of  coracobrachialis 
and  short  head  of  biceps 


Fig.  254. — Raising  the  arm  to  a  vertical  line  or  a  little  more  relaxes  the  tendon  of  the  coracobrachialis 
and  short  head  of  the  biceps  muscle  and  allows  the  lesser  tuberosity  of  the  humerus  to  pass  beneath  it  when  the 
arm  is  rotated  inward  to  place  the  hand  on  the  opposite  shoulder. 


Prominence  formed  by 
the  head  of  the  humerus' 


\ 


Fig.  255. — Posterior  luxation  of  the  shoulder.  The  head  of  the  humerus  makes  a  prominence  beneath  tne 
spine  of  the  scapula  and  the  arm  is  rotated  inward.  (From  a  photograph  of  author's  patient  by  Dr.  A.  P.  C. 
Ashhurst.) 


THE  SHOULDER-GIRDLE.  241 

The  infraspinatus,  teres  minor,  and  sometimes  the  subscapularis  muscles  are 
ruptured  and  frequently  there  are  accompanying  fractures  of  the  tuberosities  or  some 
part  of  the  scapula.  The  head  makes  a  prominence  posteriorly  and  the  arm  hangs  to 
the  side  and  in  a  position  of  inward  rotation.  Reduction,  if  the  injury  is  recent,  is 
likely  to  be  easily  effected  by  pushing  the  head  directly  forward  into  its  socket. 

FRACTURES  OF   THE   SHOULDER-GIRDLE   AND   UPPER   END 

OF   THE   HUMERUS. 

FRACTURES   OF  THE  CLAVICLE. 

Fractures  of  the  clavicle  divide  with  those  of  the  radius  the  distinction  of  being 
the  most  frequent  of  any  in  the  body. 

The  clavicle  is  most  often  broken  in  its  middle  third,  next  in  its  outer,  and,  lastly, 
in  its  inner  third. 

Fracture  of  the  Inner  Third  of  the  Clavicle. — This  is  the  rarest  frac- 
ture of  the  clavicle  and  has  its  main  anatomical  interest  in  relation  to  the  costoclavic- 
ular ligament.  This  ligament  runs  obliquely  upward  and  outward  from  the  upper 
surface  of  the  cartilage  of  the  first  rib  to  the  lower  surface  of  the  clavicle,  a  distance 
of  2  cm.  (4  in.). 

Immediately  in  front  of  the  outer  portion  of  this  ligament  is  the  insertion  of  the 
tendon  of  the  subclavius  muscle.  The  line  of  the  fracture  may  be  either  transverse 
or  oblique ;  if  oblique  it  follows  the  same  direction  as  do  the  fractures  of  the  middle 
third  of  the  bone,  viz. ,  from  above,  downward  and  inward.  The  displacement  of 
the  inner  fragment  is  upward  and  of  the  outer  fragment  downward.     The  displace- 


FiG.  256. — Fracture  of  the  clavicle  just  outside  of  the  middle,  with  the  customary  deformity. 

ment  of  the  inner  fragment  upward  is  promoted  by  the  attachment  of  the  clavicular 
origin  of  the  sternomastoid  muscle:  it  is  opposed  by  the  costoclavicular  (rhomboid) 
ligament  and  to  a  less  extent  by  the  subclavius  muscle. 

Fracture  of  the  Middle  Third  of  the  Clavicle. — The  clavicle  is  most 
frequently  broken  in  the  outer  half  of  its  middle  third.  The  bone  at  this  part  is  most 
slender;  it  is  here  that  the  anterior  curve  passes  into  the  posterior;  and,  finally,  it  has 
fewer  muscular  attachments  at  this  situation.  The  upper  surface  has  arising  from  its 
inner  third  the  clavicular  origin  of  the  sternomastoid  muscle.  Its  middle  third  has 
no  muscular  attachments,  and  on  its  outer  third  is  the  trapezius  muscle.  On  the 
lower  or  anterior  surface  on  its  inner  half  is  the  clavicular  origin  of  the  pectoralis 
major  and  on  its  outer  third  is  the  deltoid.  This  leaves  the  outer  half  of  the  middle 
third  free  from  muscular  attachments,  with  the  exception  of  the  subclavius  on  its 
under  surface.      It  is  through  this  part  of  the  bone  that  fractures  occur. 

Sometimes  in  children  the  line  of  fracture  is  transverse,  but  most  often  it  is 
oblique  and  always  in  the  direction  from  above  downward  and  inward. 

The  displacement  of  the  inner  fragment  is  upward,  and  of  the  outer  fragment 
downward  and  inward.  This  produces  the  deformity  seen  in  Fig.  256.  The  inner 
fragment  is  pulled  up  by  the  clavicular  origin  of  the  sternomastoid  muscle.  The 
support  of  the  clavicle  being  gone,  the  shoulder  falls  down  and  in.  It  is  impelled  in 
that  direction,  first,  by  the  weight  of  the  upper  extremity,  and,  secondly,  by  the  action 
of  the  axillary  fold  muscles, — pectoralis  major  and  minor  anteriorly  and  teres  major 
and  latissimus  dorsi  posteriorly,  and  by  the  subclavius  to  some  extent.  The  anterior 
edge  of  the  scapula  rotates  inward  and  its  posterior  edge  tilts  outward. 

In  this  manner  overlapping  is  produced,  and  measurements  of  the  injured  and 
healthy  sides  taken  from  the  sternoclavicular  to  the  acromioclavicular  joint  will 
show  some  shortening  on  the  injured  side.  As  the  continuity  of  the  shoulder-girdle 
16 


242 


APPLIED    ANATOMY. 


has  been  destroyed  and  its  prop-like  action  lost,  its  function  of  abduction  ceases,  and 
the  patient  is  unable  properly  to  elevate  the  arm.  Sometimes  the  brachial  plexus  or 
subclavian  vessels  are  injured  i)y  the  inner  end  of  the  outer  fragment.  The  artery 
passes  beneath  the  middle  of  the  bone,  the  vein  being  to  its  inner  side  and  the 


Trapezius 
Coracoid  process 


Deltoi 


Clavicular  fibres 
of  sternomastoid 

—  Brachial  plexus 

Suliclavian  vessels 


Pectoralis  minor 


Pectoralis  major 


Fig.  257. — Fracture  of  the  clavicle  just  outside  the  middle.  The  outer  fragment  is  displaced  downward  and 
inward  and  the  inner  fragment  upward.  The  brachial  plexus  and  subclavian  vessels  are  behind  the  inner  end  of 
the  outer  fragment. 

brachial  plexus  to  its  outer  side.  We  have  operated  on  one  such  case  of  injury  to 
the  brachial  plexus;  and  cases  of  haematoma  arising  from  injury  to  the  veins  and 
aneurism  from  injury  to  the  artery  have  been  recorded. 

Treatmeyit. — When  the  line  of  fracture  is  oblique  and  in  an  adult,  healing  with  a 
certain,  often  considerable,  amount  of  deformity  is  almost  constant,  the  only  efficient 


Fig.  258. — Showing  how  the  shoulder  falls  inward  and  the  posterior  edge  of  the  scapula  tilts  outward  when  the 
prop-like  action  of  the  clavicle  is  destroyed  by  fracture. 

way  of  combating  its  occurrence  is  to  place  the  patient  in  bed  on  his  back.  This  is  the 
best  way  of  removing  the  weight  of  the  arm,  of  quieting  the  muscles,  and  by  pressure 
of  the  scapula  close  to  the  thorax  of  levering  the  shoulder  out  (see  Fig.  258). 


THE  SHOULDER-GIRDLE. 


243 


Fracture  of  the  Outer  Third  of  the  Clavicle. — Attached  to  the  outer  third 
of  the  clavicle  on  its  under  surface,  extending  not  quite  to  its  end,  are  the  coraco- 
clavicular  (conoid  and  trapezoid)  ligaments.  The  conoid  inserts  into  the  conoid 
tubercle  near  the  posterior  edge  of  the  clavicle,  while  the  trapezoid  is  broader  and 
passes  from  the  conoid  tubercle  outward  and  anteriorly  not  quite  to  the  extremity 
of  the  bone  (see  Fig.  267).  The  bone  may  be  fractured  either  through  the  part  to 
which  the  conoid  and  trapezoid  ligaments  are  attached,  or  between  them  and  the  end 
of  the  bone,  a  distance  of  about  2  cm.  (i  in.).  The  line  of  the  fracture  is  either 
transverse  or  inclines  backward  and  outward  (see  Fig.  259). 

The  displacement  of  the  outer  fragment  is  downward  and  inward.  If  the  fracture 
is  through  the  ligaments  the  displacement  is  not  marked.  If  beyond  the  ligaments, 
the  shoulder  drops,  carrying  down  the  outer  fragment,  and  the  inner  fragment  may 
be  elevated  slightly  above  the  outer  one,  but  the  up-and-down  displacement  is  not 


Pectoralis  minor 


Pectoralis  major 


Latissimus  dorsi 


Teres  major 

Fig.  259. — Fracture  of  the  outer  end  of  the  clavicle.    The  outer  fragment  is  drawn  inward  by  the  pectoralis  major 

latissimus  dorsi,  and  teres  major  muscles. 

conspicuous.  In  many  cases  the  anteroposterior  displacement  is  very  marked  and 
peculiar.  The  outer  fragment  is  bent  sharply  inward  at  the  site  of  fracture,  producing 
a  deformity  which  is  pathognomonic.  It  is  caused  by  the  curved  shape  of  the  bone  at 
this  point,  by  the  weight  of  the  arm,  and  by  the  action  of  the  muscles  passing  from 
the  shoulder  to  the  trunk,  especially  the  pectoralis  major  (see  Fig.  259). 

Treatment. — As  the  deformity  is  not  very  marked  any  of  the  usual  bandages, 
such  as  those  of  Velpeau,  Desault,  or  posterior  figure  eight  are  fairly  satisfactory. 


FRACTURES  OF  THE  SCAPULA. 

While  fractures  of  the  scapula  are  not  common,  there  are  a  few  anatomical  facts 
in  reference  to  the  scapula  and  its  muscles  which  are  worth  calling  attention  to. 

The  scapula  is  liable  to  be  fractured  more  or  less  transversely  through  the  body 
below  the  spine;  the  acromion  and  coracoid  processes  have  been  broken;  it  has  also 
been  fractured  through  the  surgical  neck,  and  the  glenoid  process  has  been  chipped  off. 


244  APPLIED   ANATOMY. 

Fracture  Through  the  Body. — The  scapula  has  attached  to  its  under  surface 
the  subscapularis  muscle,  along  its  posterior  border  is  the  serratus  anterior  (magnus) 
and  rhomboids,  to  its  dorsum  and  edge  below  the  spine  are  attached  the  infraspina- 
tus, teres  minor,  and  teres  major  muscles.  These  are  covered  by  a  strong,  tough 
fascia  which  dips  between  them  to  be  attached  to  the  bone. 

Bearing  these  facts  in  mind  it  is  readily  appreciated  why  in  many  of  these 
fractures,  which  usually  traverse  the  bone  below  its  spine  from  the  axillary  to  the 
vertebral  border,  the  displacement  is  slight,  and  why  healing  occurs  with  some 
appreciable  deformity  but  with  little  disability. 

If,  however,  the  fracture  is  low  down,  breaking  off  the  lower  angle,  then  the  teres 
major  and  lower  portion  of  the  serratus  anterior  (magnus)  muscles  displace  the  frag- 
ment toward  the  axilla,  and  this  is  to  be  borne  in  mind  in  treating  the  injury. 

Fracture  of  the  acromion  process  is  more  rare  than  would  be  expected. 
It  is  the  result  of  direct  violence,  and  the  displacement  and  disability  resulting  from 
the  injury  are  slight.  The  acromion  is  covered  by  a  dense  fibrous  expansion  from 
the  trapezius  above  and  the  deltoid  below,  and  these  prevent  a  wide  separation  of 
the  fragments. 

Fracture  of  the  coracoid  process  is  also  rare  and  may  occur  from  muscular 
contraction  or  direct  violence,  as  in  luxation  of  the  shoulder.  It  might  be  thought 
that  owing  to  the  action  of  the  pectoralis  minor,  coracobrachialis,  and  short  head  of 
the  biceps  muscles,  which  are  attached  to  it,  it  would  be  widely  displaced,  but  this 
is  not  so,  for  the  conoid  and  trapezoid  ligaments  still  hold  it  in  place. 

Fractures  through  the  surgical  neck  are  not  common.  They  pass  down 
through  the  suprascapular  notch  and  across  the  glenoid  process  or  head,  in  front  of  the 
base  of  the  spine  and  behind  and  parallel  with  the  glenoid  fossa.  The  tendency  of 
the  outer  fragment  to  be  dragged  down  by  the  weight  of  the  arm  is  resisted  by  the 
coraco-acromial  and  coracoclavicular  (conoid  and  trapezoid)  ligaments  as  well  as  by 
the  inferior  transverse  ligament,  which  runs  from  one  fragment  to  the  other  from 
the  base  of  the  spine,  on  the  posterior  surface,  to  the  edge  of  the  glenoid  cavity. 
These  ligaments  all  remain  intact. 

Fracture  through  the  glenoid  process,  chipping  off  a  greater  or  less  por- 
tion of  the  articular  surface,  is  rarely  diagnosed.  It  occurs  sometimes  in  cases  of 
luxation.  The  long  head  of  the  triceps  muscle  may  be  fastened  to  the  detached  frag- 
ment and  is  liable  to  pull  it  downward  and  therefore  some  interference  with  the  func- 
tions of  the  joint  would  be  apt  to  remain  and  prevent  complete  recovery. 

FRACTURES  OF  THE  UPPER   END  OF  THE   HUMERUS. 

Fractures  of  the  upper  end  of  the  humerus  may  occur  through  the  anatomical 
neck,  through  the  tuberosities,  detaching  one  or  both,  and  through  the  surgical  neck 
just  below  the  tuberosities.  These  fractures  are  frequently  associated  with  luxation 
of  the  head  of  the  bone. 

Fracture  through  the  Anatomical  Neck. — This  occurs  as  the  result  of  direct 
violence  and  most  often,  though  not  always,  in  old  people.  The  line  of  fracture  does 
not  always  follow  exactly  the  line  of  the  anatomical  neck,  but  may  embrace  a  portion 
of  the  tuberosities.  The  fracture  may  or  may  not  be  an  entirely  intracapsular  one. 
The  capsule  in  its  upper  or  outer  portion  is  thickened  at  its  humeral  end  by  more  or 
less  blending  with  the  tendons  of  the  muscles  which  pass  over  it.  The  capsule  at  this 
point  is  attached  to  the  anatomical  neck  almost  or  quite  up  to  the  articular  surface. 
On  the  under  side  to  the  contrary  it  passes  about  a  centimetre  below  the  articular 
surface  and  doubles  back  to  be  attached  somewhat  closer  to  it  (see  Fig.  266,  page  253). 

In  consequence  of  this  arrangement,  a  fracture  which  follows  the  anatomical  neck 
would  be  within  the  joint  below  and  just  outside  of  it  above.  As  a  matter  of  fact, 
some  of  these  fractures  are  intra-  and  some  partly  extracapsular.  This  influences  the 
amount  and  character  of  the  displacement  and  the  course  of  healing.  If  the  fracture 
is  entirely  intracapsular,  bony  union  may  not  occur,  as  no  callus  may  be  thrown  out 
by  the  upper  fragment  and  atrophy  of  the  fragment  may  ensue.  The  fragment  is 
apt  to  be  much  displaced,  being  tilted  and  lying  to  the  inner  side  anteriorly. 
Sometimes  it  is  entirely  extruded  from  the  joint.  In  one  case  we  have  seen  it  lodged 
in  front  under  the  anterior  axillary  fold. 


'i't 


«    f 


THE  SHOULDER-GIRDLE.  245 

The  signs  and  symptoms  will  vary  much,  according  to  the  position  of  the  head, 
and  a  positive  diagnosis  may  be  impossible.  A  thorough  knowledge  of  the  surface 
anatomy  is  essential  in  these  cases  and  a  careful  comparison  should  be  made  with  the 
opposite  healthy  shoulder.  Impaction  sometimes  occurs,  and  is  said  to  be  most 
often  of  the  upper  fragment  into  the  lower,  sometimes  splitting  it  and  detaching  to  a 
certain  extent  one  of  the  tuberosities.  Sometimes  it  is  the  lower  fragment  which  is 
impacted  into  the  upper. 

Fractures  through  the  Tuberosities. — Like  the  former  these  are  often 
accompanied  by  luxation,  especially  if  one  or  both  of  the  tuberosities  is  detached. 
These  fractures  are  frequently  blended  with  fracture  through  the  anatomical  neck.  In 
this  fracture,  however,  the  influence  of  the  muscles  is  to  be  remembered.  The  supra- 
spinatus,  infraspinatus,  and  teres  minor  insert  into  the  greater  tuberosity,  and  the  sub- 
scapularis  into  the  lesser.  The  line  of  fracture  may  pass 
through  their  insertions  and  the  displacement  may  be  slight. 
The  upper  fragment  is,  however,  liable  to  be  tilted  out- 
ward by  the  contraction  of  the  supraspinatus  muscle,  which 
is  attached  to  the  upper  portion  of  the  upper  fragment,  while 
there  is  no  muscle  attached  below  to  counteract  it.  In  this 
case  the  shaft  of  the  humerus  is  drawn  up  and  out  by  the 
deltoid  and  is  felt  beneath  the  acromion  process.  There  is 
but  little  rotatory  displacement  of  the  upper  fragment  because 
the  subscapularis  anteriorly  is  neutralized  by  the  infraspinatus 
and  teres  minor  posteriorly. 

In  those  instances  in  which  there  is  not  much  displace-  \ 

ment  of  the  upper  fragment,  the  lower  one  may  be  drawn 
inward  and  forward  by  the  action  of  the  muscles  of  the  ax- 
illary folds. 

Fractures  detaching  the  tuberosities  are  almost  always 
accompanied  by  luxation.  If  the  greater  tuberosity  alone  is 
detached,  it  is  drawn  up  beneath  the  acromion  by  the  supra- 
spinatus. 

In  all  these  fractures  the  subsequent  disability  is  often  Fig.  260.— Fracture  through 
great  and  the  prognosis  is  unfavorable.  They  are  amongst  ^eruf  ^"""'"^^ """''  °^ ""'  ^"^ 
the  hardest  in  the  body  to  correctly  diagnose.     They  are 

treated  sometimes  with  a  shoulder-cap  and  sometimes  with  the  arm  in  the  abducted  . 
position  while  the  patient  is  kept  in  bed.     Epiphyseal  separation  will  be  alluded  to 
farther  on. 

Fractures  of  the  Surgical  Neck. — These  are  the- most  common  fractures 
of  the  humerus.  The  surgical  neck  of  the  humerus  is  usually  defined  as  the  portion 
between  the  lower  part  of  the  tuberosities  and  the  upper  edge  of  the  tendons  of  the 
pectoralis  major  and  latissimus  dorsi  muscles.  Often,  however,  the  tendons  of  these 
two  muscles  continue  almost  or  quite  up  to  the  tuberosities,  hence  there  is  little  or 
no  interval  here  and  the  line  of  fracture  then  passes  through  the  upper  part  of  these 
tendons. 

The  fractures  occur  both  from  direct  and  indirect  violence  and  the  direction  of 
the  force  has  probably  something  to  do  with  the  displacement  of  the  fragments. 

Displace7nent. — It  can  readily  be  seen  that  if  a  blow  is  received  on  the  humerus 
below  the  tuberosities  while  the  arm  is  in  a  somewhat  abducted  position  the  head  will 
be  supported  by  the  glenoid  process  (head)  of  the  scapula  and  the  bone  will  be 
fractured  through  the  surgical  neck  and  driven  in  towards  the  body,  and,  as  the 
scapula  is  supported  posteriorly,  the  movable  lower  fragment  is  displaced  anteriorly. 
After  the  fracture  has  occurred,  and  possibly  in  some  cases  aided  by  the  peculiar 
direction  of  the  fracturing  force,  the  lower  fragment  is  drawn  upward  by  the  muscles 
running  from  one  side  of  the  fracture  to  the  other.  These  are  the  deltoid,  biceps, 
coracobrachialis,  and  the  long  head  of  the  triceps.  The  typical  displacement  is 
for  the  upper  fragment  to  be  abducted  and  some  say  rotated  out — this  latter  is  not 
without  doubt.  The  lower  fragment  is  certainly  in  front  and  to  the  inside  of  its 
normal  position. 

The  abduction  of  the  upper  fragment  is  due  to  the  unresisted  action  of  the  supra- 
spinatus muscle.     The  subscapularis  in  front  and  the  teres  minor  and  infraspinatus 


246 


APPLIED    ANATOMY. 


behind  nearly  or  quite  balance  each  other,  thus  causing  little  or  no  lateral  displace- 
ment. The  displacement  inward  and  anteriorly  of  the  lower  fragment,  is  due  to  the 
action  of  the  violence  as  already  detailed  and  is  aided  by  the  action  of  the  pectoralis 
major,  the  teres  major,  and  latissimus  dorsi  muscles,  all  of  which  pass  from  the  lower 
fragment  just  below  the  seat  of  fracture  inward  to  the  trunk. 

The  longitudinal  displacement  is  peculiar.  As  the  lower  fragment  is  drawn  up 
its  upper  end  may  be  felt  through  the  deltoid  muscle  below  and  toward  the  inner  side 
of  the  acromion.  While  the  displacement  in  most  cases  is  not  marked,  in  some  the 
lower  fragment  can  readily  be  felt  in  the  axilla  (Fig.  261). 

Sometimes  instead  of  the  lower  fragment  being  displaced  inward  it  goes  outward. 
In  this  case  as  it  rises  it  pushes  the  head  and  tilts  it  inward  while  it  passes  farther 
outward. 

The  diagnosis  is  to  be  made  by  a  careful  examination  and  comparison  with  the 
opposite  healthy  member.     The  head   is  recognized   to   be   in  the  glenoid  cavity, 

^ —  ^  Acromion  process 

Supraspinatus  muscle 


Clavicle 


Subscapularis 
muscle 


Pectoralis  minor 
muscle 


Deltoid  muscle 


Long  head 
'    of  biceps 


Pectoralis 
major 


Pectoralis  major 


Latissimus  dorsi 
and  teres  major 


Fig.  261. — Fracture  of  the  surgical  neck  of  the  humerus.  The  upper  fragment  is  held  out  by  the  supra- 
spinatus, while  the  lower  fragment  is  drawn  in  by  the  pectoralis  major,  latissimus  dorsi,  and  teres  major 
muscles  and  the  arm  abducted  by  the  deltoid. 


crepitus  is  felt,  the  upper  end  of  the  lower  fragment  can  often  be  palpated,  and  on 
rotating  the  arm  the  head  of  the  bone  is  found  to  lie  stationary. 

Treahnent. — The  ideal  treatment  is  extension  with  the  patient  in  bed  and  the 
arm  abducted.  As  the  upper  fragment  cannot  be  brought  in,  an  eflort  may  be 
made  to  bring  the  lower  one  out.  As  these  are  usually  treated  as  walking  cases  a 
common  dressing  employed  is  a  shoulder-cap  with  the  arm  bound  to  the  side;  some- 
times an  axillary  pad  is  used  to  keep  the  arm  away  from  the  body.  In  cases  of 
fracture  associated  with  luxation  of  the  head  of  the  bone,  replacement  can  sometimes 
be  effected  by  traction  in  the  abducted  position  and  pressure  on  the  head,  general 
anaesthesia  being  used  (see  description  of  direct  method  of  reduction  under  dis- 
location of  the  shoulder,  page  236). 


THE  SHOULDER-GIRDLE. 


247 


To  aid  in  the  reduction  McBurney  devised  a  hook  which  he  inserts  into  the  upper 
fragment,  puUing  it  toward  the  glenoid  cavity. 


Supraspinatus 
Muscle 


EPIPHYSEAL  SEPARATIONS. 

The  epiphyses  that  are  hable  to  separation  are  those  of  the  coracoid  process, 
the  acromion  process,  and  the  upper  end  of  the  humerus. 

Separation  of  the  Coracoid  Epiphysis. — The  coracoid  process  has  three 
separate  centres  of  ossification  which  fuse  with  the  body  of  the  bone  from  the  fifteenth 
to  the  twentieth  year.  Therefore  displacements  occurring  before  the  latter  age  may 
be  separations  of  the  epiphysis  and  not  true  fractures,  particularly  if  the  line  of  sepa- 
ration runs  through  the  base  of  the  coracoid. 

Separation  of  the  Acromion  Epiphysis. — The  acromion  process  is  cartilag- 
inous up  to  the  fifteenth  year.  Then  two  centres  appear  and  the  epiphysis  unites 
with  the  rest  of  the  spine  of  the  scapula  about  the  twentieth  year  or  later.  The  epi- 
physeal line  runs  posterior  to  the  acromioclavicular  joint,  just  behind  the  angle  of  the 
spine  of  the  scapula.  It  has  been  suggested  that  many  cases  diagnosed  as  sprains  and 
contusions  of  the  shoulder  are  really  epiphyseal  separations  of  the  acromion  process. 

Separation  of  the  Epiphysis  of  the  Upper  End  of  the  Humerus. — The 
upper  end  of  the  humerus  has  three  centres  of  ossifica- 
tion, one  for  the  head  and  one  each  for  the  greater  and 
lesser  tuberosities.  These  three  centres  are  blended  by 
the  seventh  year,  and  the  whole  epiphysis  unites  with  the 
shaft  at  about  the  age  of  twenty-five  years. 

The  epiphyseal  line  follows  the  lower  half  of  the 
anatomical  neck  and  then  passes  outward  to  the  insertion 
of  the  teres  minor  muscle.  This  brings  the  outer  end  of 
the  epiphyseal  line  some  distance  away  from  the  joint, 
while  the  inner  portion  of  the  line  is  within  the  joint. 
Disease  of  this  region  may  therefore  follow  the  epiphyseal 
cartilage  into  the  joint.  A  separation  of  the  epiphysis 
from  injury  will  implicate  the  joint. 

The  surgical  neck  of  the  humerus  lies  a  short  dis- 
tance below  the  epiphyseal  line  and  farther  away  on  the 
outer  side  than  on  the  inner.  The  line  of  the  epiphysis 
rises  higher  in  the  centre  of  the  bone  than  on  the  sur- 
face, making  a  sort  of  cap  for  the  end  of  the  diaphysis. 
The  symptoms  of  epiphyse&l  separation  are  almost 
exactly  the  same  as  those  of  fracture  of  the  surgical  neck 
(see  page  245). 

The  supraspinatus  is  the  main  agent  in  tilting  the 
upper  fragment  outward,  while  the  muscles  inserted  into 
the  bicipital  ridges, — the  pectoralis  major  into  the  outer 
ridge  and  the  latissimus  dorsi  and  teres  major  into  the 
inner, — draw  the  lower  fragment  inward.  The  relative 
position  of  the  fragments  when  the  lower  is  displaced  outward  is  seen  in  Fig.  262. 

AMPUTATIONS  AND  RESECTIONS  OF  THE  SHOULDER. 
AMPUTATION  AT  THE  SHOULDER-JOINT. 

The  many  different  methods  of  amputating  at  the  shoulder  may  for  our  purposes 
be  divided  into  two  classes, — the  flap  method  and  the  racket  method. 

The  Flap  Method. — One  large  flap  may  be  made  to  the  outer  side  and  a 
short  one  to  the  inner  side  (Dupuytren)  or  they  may  be  made  anteroposteriorly 
(Lisfranc).  The  flap  operations  were  done  with  long  knives  by  transfixion,  as  they 
originated  before  the  discovery  of  general  anaesthesia  and  by  them  the  member  was 
removed  with  great  rapidity  (Fig.  263). 

In  DupuytrerCs  method  the  arm  was  raised  to  a  right  angle  with  the  body  and  the 
deltoid  muscle  grasped  with  one  hand  while  the  knife  was  inserted  beneath  it,  entering 


Fig.  262. — Detachment  of  the 
epiphysis  of  the  upper  end  of  the 
humerus. 


248 


APPLIED    ANATOMY. 


just  below  the  posterior  portion  of  the  acromion  process  (its  angle)  then  passing 
under  the  acromion  to  emerge  in  front  at  the  coracoid  process.  This  flap  was  turned 
up,  the  capsule  and  muscles  divided,  the  bone  turned  out,  and  while  an  assistant 
compressed  the  remaining  tissues  they  were  divided  transversely. 

Lisfrand  s  method  consisted  in  transfixing  the  posterior  axillary  fold  from  below 
upward,  entering  the  knife  in  front  of  the  tendons  of  the  latissimus  dorsi  and  teres 
major  muscles  and  bringing  it  out  a  litde  in  front  of  the  acromion.  The  joint 
was  opened  posteriorly,  the  bone  luxated,  and  an  anterior  flap  cut  from  within  out- 
ward. Sir  William  Fergusson,  probably  the  most  skilful  operator  of  his  day,  was 
partial  to  this  operation. 

The  Racket  Method. — In  this  method  the  incision  resembles  in  shape  the 


Coraco-  Long        Acro- 

acromial  head  of         mion 

ligament  biceps     process 


Deltoid 
muscle 


Supraspinatus 


Infraspinatus 


Teres  minor 


Coracobrachialis  and 
short  head  of  biceps 

Musculocutaneous 
nerve 
Median  nerve 

Internal  cutaneous  nerve 


Musculospiral 
(radial)  nerve 


Posterior  circumflex 
artery 

Subscapular  artery 
Latissimus  dorsi  and 
teres  major 
Ulnar  nerve 


Fig.  263. — Amputation  of  the  shoulder  by  anteroposterior  flaps.    The  upper  extremity  of  the  incision  passes 
between  the  coracoid  and  acromion  processes.    The  posterior  flap  is  the  larger. 


ordinary  racket,  such  as  is  used  in  tennis.  The  loop  encircles  the  arm,  while  the 
handle  begins  above  at  the  point  of  the  shoulder. 

There  are  two  operations  by  the  racket  method,  which  differ  as  to  the  position 
from  which  the  upper  portion  of  the  incision  starts. 

Larrey  s  Method. — The  operation  usually  ascribed  to  Larrey  consists  in  starting 
the  incision  at  the  anterior  end  of  the  acromion  process  and  continuing  it  straight 
down  the  arm  for  three  centimetres  (i^^  in. ).  It  then  parts,  one  branch  sweeping 
gradually  in  a  curved  line  to  the  anterior  axillary  fold  and  the  other  to  the  posterior 
axillary  fold,  an  incision,  through  the  skin  only,  passes  across  the  inner  surface  of  the 
arm  joining  the  two  branches.  The  flaps  having  been  turned  anteriorly  and  poste- 
riorly, the  joint  is  opened  by  cutting  on  the  head  of  the  bone,  first  posteriorly,  then 
above,  and  then  anteriorly.  Tilting  the  head  outward  the  inferior  portion  of  the 
capsule  is  divided  and  the  bone  loosened  from  the  soft  parts.  These  are  com- 
pressed by  the  fingers  of  an  assistant  and  cut. 


THE  SHOULDER-GIRDLE.  249 

Spence'  s  Method. — A  modification  of  Larrey's  procedure,  attributed  to  Spence 
by  the  British  and  to  S.  Fleury  by  the  French,  consists  in  commencing  the  incision 
just  outside  of  the  coracoid  process  in  the  interval  between  it  and  the  acromion 
process.  This  modification  is  probably  the  best  form  of  procedure  for  this  locality 
and  is  the  one  which  will  be  discussed  here.  It  will  be  noticed,  however,  that  it 
practically  changes  the  operation  of  Larrey  from  one  with  anteroposterior  flaps  to  one 
with  a  single  external  flap,  as  in  the  method  of  Dupuytren.     (Fig.  263). 

The  incision  begins  just  below  the  coraco-acromial  ligament  and  lies  deep  in  the 
hollow  formed  by  the  anterior  concave  surface  of  the  outer  third  of  the  clavicle.  It 
divides  the  fibres  of  the  deltoid  muscle  longitudinally  a  short  distance  from  its  anterior 
edge.  It  will  be  recalled  that  the  deltoid  muscle  covers  the  coracoid  process  and 
extends  just  to  its  inner  side  to  be  attached  to  the  outer  third  of  the  lower  surface 
of  the  clavicle.  Between  it  and  the  adjoining  edge  of  the  pectoralis  major  muscle 
runs  the  cephalic  vein.  This  passes  downward  and  outward  along  the  inner  edge 
of  the  deltoid  until  it  reaches  the  outer  edge  of  the  biceps  muscle  alongside  of  which 
it  passes  down  to  the  elbow.  This  vein  will  be  cut  as  the  inner  branch  of  the 
incision  is  made.  The  bicipital  groove,  when  the  palm  of  the  hand  faces  forward, 
lies  almost  directly  below  the  coraco-acromial  ligament.  While  the  incision  is  being 
made  the  arm  is  kept  rotated  slightly  outward. 

As  the  knife  descends  it  runs  along  the  inner  side  of  the  bicipital  groove  and 
divides  the  tendon  of  the  pectoralis  major  muscle.  As  soon  as  this  tendon  is  cut  the 
incision  is  inclined  laterally.  The  incision  having  been  carried  down  to  the  bone, 
except  on  the  inside  of  the  arm,  the  deltoid  flap  is  raised  upward  and  backward.  It 
carries  with  it  the  circumflex  nerve  and  posterior  circumflex  artery. 

The  disarticulation  of  the  bone  is  apt  to  be  bungled  unless  one  knows  the  con- 
struction of  the  parts.  It  is  to  be  borne  in  mind  that  the  capsular  ligament  is  to  be 
divided  together  with  the  tendons  of  the  muscles  inserted  into  the  tuberosities.  The 
capsule  does  not  pass  across  the  anatomical  neck  to  be  inserted  into  the  tuberosities 
beyond,  and  the  mistake  is  often  made  of  cutting  on  the  anatomical  neck  and  there- 
fore frequently  the  capsule  still  remains  attached  to  the  proximal  side.  The  cut 
may  be  commenced  posteriorly  and  should  be  made  on  the  head  of  the  bone  just 
above  the  anatomical  neck.  The  arm  is  to  be  adducted  and  rotated  inward  and  the 
muscles  inserting  into  the  greater  tuberosity  cut  in  their  order,  first  the  teres  minor, 
then  the  infraspinatus  and  supraspinatus  with  the  joint  capsule  beneath  them.  Then 
comes  the  long  head  of  the  biceps,  and  the  arm  now  being  rotated  outward,  the 
tendon  of  the  subscapularis  is  divided.  In  cutting  the  muscles  and  capsule  across 
the  top  of  the  joint,  the  arm  is  to  be  kept  close  to  the  side  of  the  body  so  as  to  tilt 
the  upper  portion  of  the  capsule  out  beyond  the  acromion  process. 

The  head  of  the  bone  can  now  be  drawn  out  sufficiently  to  allow  the  knife  to  be 
introduced  behind  it  to  divide  the  inferior  portion  of  the  capsule.  This  should  be 
detached  close  to  the  bone  so  as  to  avoid  wounding  the  axillary  artery  and  especially 
the  posterior  circumflex  artery  and  the  circumflex  nerve,  which  wind  around  the 
surgical  neck  immediately  below  and  are  to  be  pushed  out  of  the  way. 

The  division  is  completed  by  cutting  the  remaining  muscles  passing  from  the 
trunk  to  the  shaft  of  the  bone.  On  the  inner  side  may  be  an  uncut  portion  of  the 
pectoralis  major,  the  coracobrachialis,  and  short  head  of  the  biceps ;  below  is  the  long 
head  of  the  triceps  and  on  the  outer  side  are  the  teres  major  and  latissimus  dorsi. 

On  examining  the  face  of  the  stump,  posteriorly  is  seen  the  bulk  of  the  deltoid 
muscle  with  the  triceps  below,  and  then  the  latissimus  dorsi  and  teres  major  tendons 
lying  next  to  the  artery.  Anteriorly  is  the  cut  edge  of  the  deltoid  and  pectoralis 
major  with  the  coracobrachialis  and  short  head  of  the  biceps  lying  next  to  the  artery. 

To  the  outer  side  of  the  artery  lie  the  median  and  musculocutaneous  nerves. 
To  the  inner  side  are  the  ulnar  and  lesser  internal  cutaneous  nerv^es  (cutaneus  brachii 
medians')  and  the  axillary  vein.  Posteriorly  are  the  musculospiral  and  axillary 
(circumflex)  nerves. 

Sometimes  the  median  nerve  lies  in  front  instead  of  to  the  outer  side.  The  axillary 
artery  is  divided  below  the  origin  of  the  anterior  and  posterior  circumflex  arteries. 
The  bleeding  in  the  first  cut  will  be  from  the  cephalic  vein  (which  runs  between 
the  pectoralis  major  and  deltoid),  muscular  branches  of  the  posterior  and  anterior 


250 


APPLIED    ANATOMY. 


circumflex,  a  small  ascending  branch  of  the  anterior  circumflex  which  runs  in  the 
bicipital  groove,  and  the  humeral  branch  of  the  acromial  thoracic  which  accompanies 
the  cephalic  vein. 

A  glaring  and  common  mistake  in  the  performance  of  shoulder  amputations  is 
the  making  of  the  flaps  entirely  too  short,  especially  when  a  Larrey  operation  is 
attempted. 

The  avoidance  of  serious  hemorrhage  is  usually  accomplished  by  clamping  the 
small  vessels  as  the  operation  proceeds,  and  before  the  final  division  of  the  axillary 
vessels  slipping  the  fingers  behind  the  bone  and  compressing  them. 

Esmarch's  tube  has  been  used  by  encircling  the  shoulder  as  close  to  the  trunk 
as  possible,  the  tube  being  kept  from  slipping  by  a  bandage  passed  beneath  it  and 
fastened  to  the  opposite  side.  Wyeth's  pins  have  been  used  for  the  same  purpose. 
One  is  inserted  through  the  lower  edge  of  the  anterior  axillary  fold  a  little  internal 
to  its  middle  and  brought  out  above  in  front  of  the  acromion  process,  the  other  is 
entered  at  a  corresponding  point  of  the  posterior  fold  and  brought  out  above  just 
behind  the  angle  of  the  spine  of  the  scapula  or  acromion  process. 

Interscapulothoracic  Amputation. — For  malignant  growths  of  the  axilla, 
shoulder,  or  scapula,  and,  rarely,  for  injury,   the  whole  upper  extremity  with  the 

Cords  of  brachial  plexus 

Subclavian  artery 

Superficial  cervical  artery 
Trapezius 

,  Posterior  scapular  artery  coming 
Omohyoid  muscle— ^^[^^'^■Hi^^'^B^^y  /  from  the  subclavian 

"^BP>^^^^/^^^^^^^^B^^^^M||^B^^^^^^     Costocoracoid  ligament 
Scalenus  anterior  SBk^lk/  ^^H^^^^^^^^^^^^^WSIfev^     /        Deltoid 

muscle 

Transverse  cervical 
artery 

Internal  jugular 

Phrenic  nerve 

Suprascapular  artery 

Thoracic  duct 

Innominate  \ 
vein 


Subclavius  muscle 


Subclavian  vein 

Acromial  thoracic  artery 

Fig.  264. — Structures  exposed  by  excising  the  inner  portion  of  the  clavicle. 


scapula  and  part  or  whole  of  the  clavicle  have  been  removed.  Anteroposterior 
flaps  are  made. 

The  greatest  danger  is  death  from  shock  and  hemorrhage.  In  order  to  obtain 
some  idea  of  the  topography  and  vessels  involved,  see  Fig.  264. 

Excision  of  the  Clavicle. — Excision  of  the  clavicle  in  the  living  body,  like 
tracheotomy,  is  much  more  difficult  than  when  practiced  on  the  dead  body;  this 
is  due  to  the  condition  of  the  parts  for  which  operation  is  undertaken.  It  has  been 
often  excised  for  malignant  growths.  On  the  upper  anterior  surface  are  attached  the 
clavicular  origin  of  the  sternomastoid,  the  deep  cervical  fascia,  and  the  trapezius 
muscle.  Crossing  the  clavicle  near  its  middle  is  the  jugulocephalic  vein  which  some- 
times connects  the  cephalic  with  the  external  jugular.  It  is  likewise  crossed  by  the 
superficial  descending  branches  of  the  cervical  plexus.  The  external  jugular  vein, 
about  2.5  cm.  (i  in.)  above  the  middle  of  the  clavicle,  pierces  the  deep  fascia  and 
turns  inward  to  empty  into  the  internal  jugular  just  behind  the  outer  edge  of  the 
sternomastoid  muscle;  just  below  it  empties  the  thoracic  duct  at  the  junction  of  the 
internal  jugular  and  subclavian  veins.  The  subclavian  vein  is  directly  behind  the 
clavicle  and  the  left  innominate  vein  crosses  behind  the  left  sternoclavicular  joint  and 
passes  across  the  posterior  surface  of  the  sternum  just  below  or  on  a  level  with  its 


THE   SHOULDER-GIRDLE.  251 

superior  border.      The  omohyoid  muscle,  if  the  shoulder  is  drawn  outward  and  the 
head  turned  to  the  opposite  side,  is  drawn  upward  above  the  clavicle. 

Behind  the  upper  portion  of  the  clavicle  is  the  suprascapular  artery  and  above 
it  runs  the  transverse  cervical  artery,  a  branch  of  the  thyroid  axis.  Both  these 
vessels  cross  over  the  scalenus  anterior  muscle  on  which,  toward  its  inner  edge,  is 
lying  the  phrenic  nerve.  In  front  of  the  scalenus  anterior  runs  the  subclavian  vein 
and  behind  it  is  the  subcla\'ian  artery  with  the  cords  of  the  brachial  plexus  abo\'e 
and  to  its  outer  side.  Below  and  in  front  are  attached  the  pectoralis  major  and 
deltoid  muscles;  the  space  between  them  forms  the  subclavicular  triangle  and  occu- 
pies the  outer  half  of  the  middle  third  of  the  bone.  The  cephalic  vein  pierces  the 
costocoracoid  membrane  at  this  point  to  enter  the  subclavian  vein. 

On  the  under  surface  of  the  bone  is  the  subclavius  muscle,  covered  with  a 
strong  membrane.  To  the  inner  side  of  this  muscle  is  the  costoclavicular  ligament. 
Beneath  the  clavicle,  about  its  middle,  passes  the  subclavian  artery,  separated  from 
the  vein  in  front  by  the  scalenus  anterior  muscle.  Below  and  beneath  the  subclavian 
artery,  which  rests  directly  on  it,  is  the  pleura.  The  internal  mammary  artery  passes 
behind  the  inner  extremity  of  the  clavicle  opposite  the  cartilage  of  the  first  rib. 

The  clavicle  is  the  first  bone  in  the  body  to  ossify,  and  it  has  one  epiphysis  at 
its  sternal  end  which  appears  about  the  seventeenth  year  and  joins  the  shaft  from 
the  twentieth  to  the  twenty-fifth  year.  In  removing  the  bone  it  is  first  loosened  at 
its  outer  extremity  by  dividing  the  acromioclavicular  and  coracoclavicular  (conoid 
and  trapezoid)  ligaments. 

Excision  of  the  Scapula. — The  removal  of  the  scapula  necessitates  the 
division  of  a  large  number  of  muscles,  for  which  see  pages  226  and  227.  The  sub- 
scapular artery  at  the  anterior  border,  about  2.  5  cm.  ( i  in.  )  below  the  head  or  glenoid 
process,  and  the  suprascapular  at  the  suprascapular  notch,  are  to  be  ligated  before 
removing  the  bone.  Skirting  the  posterior  edge  is  the  posterior  scapular,  the 
continuation  of  the  transverse  cervical  artery;  it  is  to  be  avoided  when  detaching 
the  muscles.  The  acromial  branches  of  the  acromial  thoracic  artery  ramify  over  the 
acromion  process;  they  are  not  so  large  as  those  already  mentioned. 

Mr.  Jacobson  suggests  that  if  safety  permits  one  should  allow  the  acromion 
process  to  remain,  as  it  preserves  the  point  of  the  shoulder  and  to  some  extent,  the 
functions  of  the  trapezius  muscle. 

Excision  of  the  Head  of  the  Humerus.— The  incision  for  the  removal 
of  the  head  of  the  humerus  should  be  commenced  just  outside  of  the  coracoid 
process  and  be  carried  10  cm.  (4  in. )  downward  in  a  direction  toward  the  middle 
of  the  humerus,  where  the  deltoid  inserts.  This  incision  may  be  made  while  the  arm 
is  somewhat  abducted  but  it  does  not  go  in  the  groove  between  the  deltoid  and 
pectoralis  major  muscles.  This  groove  contains  the  cephalic  vein  and  the  humeral 
branch  of  the  acromial  thoracic  artery,  and  hence  is  to  the  inner  side  of  the  coracoid 
process  and  as  the  incision  is  to  the  outer  side,  it  passes  through  the  deltoid  near 
its  anterior  edge  (Fig.  265). 

The  incision  goes  through  the  muscle  and  exposes  the  capsule  of  the  joint.  The 
sides  of  the  wound  are  to  be  retracted  and,  if  the  long  head  of  the  biceps  muscle  is 
not  recognized  by  sight,  the  finger  is  inserted  and  the  arm  rotated.  The  bicipital 
groove  can  be  felt  and  the  tendon  identified. 

The  capsule  is  to  be  incised  along  the  outer  edge  of  the  long  tendon  of  the 
biceps  and  as  the  arm  is  rotated  inward  the  supraspinatus,  infraspinatus,  and  teres 
minor  muscles  are  to  be  detached  from  the  greater  (posterior)  tuberosity.  The 
biceps  tendon  is  again  brought  into  view  by  rotating  the  arm  outward  and  its  sheath 
(transverse  ligament)  slit  up  and  the  tendon  luxated  inward. 

The  attachment  of  the  capsule  and  subscapularis  muscle  to  the  lesser  (anterior) 
tuberosity  is  then  divided  while  the  arm  is  rotated  outward.  The  biceps  tendon  lies 
in  the  bicipital  groove  between  the  two  tuberosities.  When  the  arm  is  lying  with  the 
palm  upward,  in  a  supine  position,  the  bicipital  groove  looks  directly  anteriorly  in  a 
longitudinal  line  passing  midway  between  the  two  condyles  of  the  lower  end.  The 
position  of  the  head  and  groove  can  be  told  by  observing  the  position  of  the  condyles. 
The  head  is  directly  above  the  internal  condyle  and  the  groove  is  on  rhe  anterior  sur- 
face above  a  point  midway  between  the  condyles.     After  the  capsule  has  been  opened 


252  APPLIED    ANATOMY. 

and  the  attachments  of  the  muscles  to  the  greater  and  lesser  tuberosities  divided  and 
the  tendon  of  the  biceps  luxated  inward,  the  head  is  thrust  directly  upward  and  out 
of  the  wound  and  sawed  of^  as  low  as  desired. 

Immediately  below  the  lower  edge  of  the  tuberosities  is  the  surgical  neck.  On 
it  anteriorly  winds  the  anterior  circumflex  artery,  and  posteriorly  the  circumflex  (axil- 
lary) nerve  and  posterior  circumflex  artery.  These  should  not  be  disturbed,  for  the 
artery  will  bleed  and  injury  of  the  nerve  will  cause  paralysis  of  the  deltoid  muscle. 

Posterior  and  transverse  incisions  have  been  suggested  for  this  operation  but 
they  are  not  to  be  advised.  The  circumflex  nerve  and  posterior  circumflex  artery 
are  almost  certain  to  be  injured  and  the  functions  of  the  deltoid  are  liable  to  be 
seriously  impaired  or  altogether  lost. 

If  more  access  is  desired  than  can  be  obtained  by  a  straight  incision  as  directed, 
the  deltoid  can  be  detached  from  its  origin  along  the  outer  end  of  the  clavicle  and 


Coracoid  process 


Acromion  process 

Subscapularis  tendon  and  capsule 
/  ;,,  -      y'  Lesser  tuberosity 
Deltoid  muscle 


Bicipital  groove 


Ftg.  26s. — Resection  of  the  shoulder- joint.  The  arm  has  been  rotated  outward  so  as  to  put  the  tendon  of  the 
subscapularis  on  the  stretch.  The  long  tendon  of  the  biceps  has  been  dislocated  from  the  bicipital  groove  and  is 
held  to  the  inner  side  by  a  hook. 

acromion  process  and  turned  down.  This  does  not  interfere  with  its  nerve  supply. 
The  circumflex  nerve  going  to  the  muscle  crosses  the  humerus  at  about  the  junction 
of  the  upper  and  middle  thirds  of  the  deltoid  or  a  finger's  breadth  above  its  middle. 
After  resection  of  the  bone  the  deltoid  can  again  be  brought  up  and  sewed  to  its  pre- 
vious attachment. 

The  character  of  the  operation  depends  on  the  nature  and  extent  of  the  disease. 
The  operator  should  be  familiar  with  the  epiphyseal  line,  which  runs  from  the  inside 
upward  and  outward  in  the  line  of  the  anatomical  neck  as  far  as  the  middle  of  the 
bone,  and  then  slopes  slightly  downward  and  outward  to  reach  the  surface  almost  on 
a  level  with  the  lower  (inner)  edge  of  the  articular  surface.  As  this  is  the  site  of 
most  active  growth  of  the  humerus  in  young  subjects  this  epiphyseal  cartilage  should 
be  spared  as  much  as  possible. 

The  disability  arising  from  a  free  resection  is  so  great,  owing  to  the  loss  of 
movements  resulting  from  the  detachment  of  muscles  and  interference  with  the 
epiphyseal  cartilage,  that  formal  resections  are  rarely  performed,  but,  instead,  the 
diseased  parts  are  simply  gouged  away  and  as  much  allowed  to  remain  as  possible. 


THE    SHOULDER  GIRDLE. 


253 


It  is  to  be  remembered  that  rotation  inward  is  mostly  performed  by  the  sub- 
scapularis  and  outward  rotation  by  the  infraspinatus  and  teres  minor.  The  supra- 
spinatus  aids  abduction.  A  too  free  excision  is  liable  to  be  followed  by  a  flail-joint, 
in  which  case  the  limb  hangs  helplessly  by  the  side  with  the  dorsum  pointing  forward. 

The  axillary  fold  muscles  insert  on  the  anterior  surface  of  the  bone  and  hence 
turn  the  arm  inward  and  draw  it  in  toward  the  body,  they  do  not  compensate  for 
the  loss  of  the  muscles  attached  to  the  tuberosities. 

The  bleeding  in  the  operation  will  be  mainly  from  the  acromial  branches  of  the 
acromial  thoracic  artery  and  the  bicipital  branch  of  the  anterior  circumfiex  artery, 
which  runs  in  the  bicipital  groove. 

DISEASES  OF  THE  JOINT  AND  BURS^. 

The  shoulder-joint,  like  other  joints,  is  subject  to  inflammatory  and  other  diseases. 
These  may  be  (i)  traumatic  and  later  septic;  (2)  rheumatic  or  gouty;  (3)  tuberculous, 
with  suppuration. 

These  affections  result  in  an  eflusion  \yithin  the  joint-cavity  which  distends  the 
capsule  and  finally  tends  to  escape  at  the  weakest  points.     The   joint   is  not  a 


Supraspinatus 


Acromion  process 

Subacromial  bursa  space 


Capsule  of  joint 
Long  head  of  biceps 


Capsule  of  joint 


Glenoid  cavity 


Long  head  of  triceps 


Fig.  266. — Transverse  section  of  shoulder-joint,  illustrating  the  laxity  of  the  capsule  of  the  joint. 


complicated  one,  like  the  knee,  and  its  synovial  membrane  is  neither  so  extensive 
nor  so  elaborate. 

Traumatism  may  give  rise  to  a  synovitis,  an  inflammation  of  the  synovial  mem- 
brane, or  an  arthritis  involving  the  entire  joint  structures.  Sprains  and  other  injuries 
are  not  uncommon.  A  sprain  will  be  caused  by  a  force  which  acts  to  a  greater 
extent  than  the  normal  movements  of  the  joint  will  allow. 

Movements  of  the  Joint. — In  abduction  the  capsule  becomes  tense  at  its  lower 
portion  when  the  arm  is  at  90  degrees  to  the  trunk,  greater  abduction  is  resisted  by  the 
greater  tuberosity  impinging  on  the  acromion  process  and  the  scapula  begins  to  revolve. 

Adduction  is  resisted  both  by  the  muscles  and  by  the  ligaments.  When  the 
ligaments  only  remain,  the  head  can  be  separated  for  2  cm.  or  more  from  the  glenoid 
cavity  (see  Fig.  266).  Marked  adduction  is  usually  limited  by  the  arm  coming  in 
contact  with  the  side  of  the  body. 

If  the  humerus  is  brought  diagonally  across  the  chest  the  scapula  begins  to 
move  and  its  posterior  edge  and  lower  angle  turn  forward.  As  the  humerus  is 
adducted  the  deltoid  and  supraspinatus  are  made  tense  and  the  head  is  drawn  up  in 
its  socket.  When  the  muscles  are  paralyzed  the  weight  of  the  upper  extremity 
allows  the  head  to  fall  and  a  distinct  depression  can  be  seen  beneath  the  acromion 
process.      In  paralysis  of  the  deltoid  this  is  particularly  noticeable. 


254 


APPLIED    ANATOMY. 


If  traction  is  made  on  the  arm,  the  muscles  are  the  resisting  agents.  If  the  arm 
is  in  a  position  of  adduction,  those  going  from  the  humerus  to  the  scapula,  as  the 
deltoid,  supraspinatus,  biceps,  and  triceps,  act.  If  in  abduction,  then  also  those 
from  the  humerus  to  the  trunk,  like  the  pectoralis  major  and  latissimus  dorsi,  are 
brought  into  play.  The  part  played  by  the  deltoid  and  trapezius  should  be  noted. 
If  the  arm  is  down  by  the  side  and  traction  is  made  on  it,  the  force  is  transmitted 
from  the  humerus  in  a  direct  line  through  the  deltoid  and  the  upper  fibres  of  the 
trapezius  to  their  attachment  to  the  spine  and  superior  curved  line  of  the  occiput. 
If,  on  the  contrary,  the  traction  is  made  while  the  arm  is  raised  above  the  level  of  the 


Superior  acromioclavicular  ligament 


Tendon  of  supra 
spinatus  muscle 


Acromion  proces 


Clavicle 


Conoid  ligament 
Trapezoid  ligament  ' 

Coraco- acromial  ligament 
Coracoid  process 

Coracohumeral  ligament 
Coracobrachialis  muscle 
Short  head  of  biceps 


Long  head  of  biceps 


Pectoralis  major  muscle 


Fig.  267. — Acromioclavicular  and  shoulder  joints. 

shoulder,  the  force  is  transmitted  through  the  axillary  fold  muscles  as  well  as  by  the 
deltoid  and  continued  through  the  lower  fibres  of  the  trapezius.  In  either  case  the 
muscles  are  the  resisting  agents  and  not  the  ligaments.  Abduction  to  more  than  a 
right  angle  is  resisted  by  the  contact  of  the  greater  tuberosity  with  the  under  surface 
of  the  acromion  process  and  coraco-acromial  ligament  and  the  under  side  of  the  cap- 
sular ligament  is  made  tense.  The  raising  of  the  arm  to  90  degrees  is  performed 
by  the  supraspinatus  and  deltoid  muscles  of  the  scapula  and  beyond  this  by  the 
serratus  anterior  and  other  muscles. 

Inward  rotation  is  limited  by  the  infraspinatus  and  teres  minor  muscles  and  by 
tension  of  the  upper  portion  of  the  capsule.  Outward  rotation  is  limited  by  the  sub- 
scapularis  and  upper  portion  of  the  capsule.  The  humerus  rotates  on  its  long  axis 
97°   (Macalister). 


THE  SHOULDER-GIRDLE.  255 

Subacromial  Bursa. — Separating  the  greater  tuberosity  from  the  deltoid 
muscle,  the  acromion  process,  and  coraco-acromial  ligament,  is  the  large  subacromial 
bursa.  It  does  not  communicate  with  the  joint,  except  rarely  in  old  people.  Effu- 
sions into  it  cause  an  increased  prominence  of  the  deltoid  muscle,  and  pus  seeking 
an  outlet  is  likely  to  show  itself  at  the  anterior  edge  of  the  muscle  and  less  often  at 
its  posterior  edge.  These  effusions,  which  are  liable  to  be  present  from  contusions, 
sprains,  etc. ,  should  not  be  mistaken  for  intra-articular  accumulations. 

Biceps  Tendon. — The  long  tendon  of  the  biceps  muscle  enters  the  joint 
through  the  bicipital  groove  between  the  two  tuberosities.  With  the  arm  hanging 
by  the  side  it  points  directly  forward;  it  passes  over  the  head  of  the  humerus  and 
under  the  coraco-acromial  ligament  about  midway  between  the  coracoid  and  acro- 
mion processes  to  insert  into  the  upper  edge  of  the  glenoid  cavity.  It  is  covered 
by  a  synovial  sheath  which  passes  with  it  through  the  opening  in  the  capsule  and  a 
short  distance  along  the  bicipital  groove.  As  this  sheath  does  not  communicate  with 
the  joint  the  tendon  is  in  one  sense  extra-articular.      It  is  held  in  the  groove  by  a 


Injection  following  the 
long  tendon  of  the  biceps 


Prolongation  under  the  tendon 
of  the  subscapularis  muscle 


Fig.  26S. — Shoulder- joint  distended  with  injection,  showing  the  position  assumed  by  the  humerus. 


fibrous  expansion,  extending  from  the  pectoralis  major  tendon  below  to  the  capsule 
above,  called  the  tra7isverse  fnwieral  ligament.  This  ligament  is  so  strong  that  luxa- 
tion of  the  tendon  is  uncommon;  even  when  the  humerus  is  luxated  the  tendon  is 
rarely  displaced. 

Subscapular  Bursa. — Beneath  the  tendon  of  the  subscapularis  there  is  a  bursa 
which  frequently  communicates  with  the  joint.  This  opening  tends  to  weaken  the 
capsule  and  it  is  at  this  point  and  just  below  that  the  head  bursts  through  in  disloca- 
tions. 

Infraspinatus  Bursa. — The  capsule  of  the  joint  and  the  synovial  membrane 
may  be  prolonged  beyond  the  rim  of  the  glenoid  cavity  under  the  tendon  of  the 
infraspinatus,  or  a  bursa  at  this  point  may  communicate  with  the  joint. 

Other  bursae  may  be  present,  but  are  unimportant.  One  is  between  the 
coracoid  process  and  the  capsule  and  another  under  the  combined  tendon  of  the 
coracobrachialis  muscle  and  the  short  head  of  the  biceps. 

Effusions  in  the  Shoulder-joint. — Liquid  accumulations  occur  both  from 
injury  and  disease.  The  liability  of  confounding  them  with  those  in  the  subacromial 
bursa  has  been  alluded  to  above.  As  a  result  of  disease,  most  often  osteo-arthritis  or 
tuberculosis,  considerable  liquid  may  accumulate  in  the  joint.  As  the  tension  in- 
creases the  arm  becomes  abducted  about  50  degrees  and  the  effusion  tends  to  escape 
through  the  openings  in  the  capsule  (Fig.  268). 


2  56  APPLIED    ANATOMY. 

A  distention  of  the  joint  will  cause  the  "deltoid  to  be  more  prominent.  If  the 
affection  is  in  an  old  person,  as  is  liable  to  be  the  case  in  osteo-arthritis,  there 
is  apt  to  be  a  communication  with  the  subacromial  bursa  and  this  will  become  dis- 
tended. If  the  liquid  is  purulent  it  has  a  tendency  to  work  its  way  laterally  under 
the  deltoid  and  break  through  at  its  anterior  or  posterior  borders  and  show  itself  at 
the  folds  of  the  axilla. 

In  osteo-arthritis  {arthritis  deformafis^  the  long  tendon  of  the  biceps  as  it  passes 
through  the  joint  may  be  dissolved  and  the  belly  of  the  muscle  then  contracts  and  forms 
a  lump  on  the  middle  of  the  arm  anteriorly. 

Pus  frequently  finds  an  exit  along  the  bicipital  groove  and  follows  it  downward 
and  shows  itself  just  at  the  edge  of  the  anterior  axillary  fold  near  the  middle  of  the  arm. 

If  the  pus  passes  out  by  way  of  the  subscapular  bursa  it  passes  below  the 
subscapular  tendon  and  into  the  axilla  anteriorly.  If  it  passes  backward  it  may 
emerge  through  the  bursa  beneath  the  infraspinatus  muscle,  and  then  either  work  its 
way  downward  into  the  posterior  portion  of  the  axilla,  or  if  it  works  upward  may 
travel  either  above  or  below  the  spine  of  the  scapula  and  show  itself  on  the  dorsum. 

THE  AXILLA. 

The  axilla  is  a  wedge-shaped  space  with  its  apex  upward,  formed  between  the 
arm  and  chest  at  their  junction.  It  serves  as  a  passage-way  for  the  arteries,  veins, 
nerves,  and  lymphatics  passing  between  the  trunk  and  the  upper  extremity.  It  is 
frequently  the  site  of  growths  and  abscesses,  requiring  operations  which  necessitate  a 
knowledge  especially  of  its  blood-vessels  and  lymphatics. 

Extent. — Its  apex  lies  between  the  clavicle  and  scapula  above  and  the  first  rib 
beneath.  Its  base  is  formed  by  the  skin  and  fascia  stretched  between  the  anterior  and 
posterior  axillary  folds.  It  is  spoken  of  as  having  four  walls:  inner,  outer,  anterior, 
and  posterior. 

The  inner  wall  is  formed  by  the  first  four  ribs  and  interspaces  and  the  corres- 
ponding serrations  of  the  serratus  anterior  (magnus)  muscle. 

The  outer  wall  is  nothing  more  than  the  chink  formed  by  the  union  of  the  two 
axillary  folds.  Above  is  the  lesser  tuberosity  of  the  humerus  and  subscapularis  ten- 
don, lower  down  are  the  coracobrachial  and  biceps  muscles. 

The  anterior  wall  is  formed  by  the  pectoralis  major  and  minor  muscles  with  the 
fascia  enveloping  them. 

The  posterior  wall  is  formed  by  the  subscapularis  above  and  the  teres  major  and 
latissimus  dorsi  muscles  below. 

Axillary  Fascia. — The  name  axillary  fascia  is  given  to  the  fascia  which  closes 
the  axillary  space  and  forms  its  base.  It  is  stretched  across  from  the  lower  edge  of 
the  pectoralis  major  in  front  to  the  lower  edge  of  the  teres  major  and  latissimus  dorsi 
behind.  On  the  inner  wall  it  is  continuous  with  the  fascia  covering  the  serratus 
anterior  (magnus)  and  side  of  the  chest;  when  it  reaches  the  vessels  at  the  apex  of 
the  axilla  it  is  reflected  around  them  to  form  the  sheath. 

On  the  outer  wall  it  passes  from  the  pectoralis  major  in  front,  over  the  coraco- 
brachialis  muscle  beneath,  blends  with  the  sheath  of  the  vessels,  and  then  passes  to 
the  posterior  wall,  covering  the  subscapularis  above  and  the  teres  major  and  latissi- 
mus dorsi  below.  At  the  lower  edge  of  this  latter  muscle,  which  is  a  little  lower  than 
the  pectoralis  major,  it  passes  across  the  axilla  (Fig.  269). 

Anteriorly  the  fascia  covers  the  pectoralis  major  muscle;  at  its  lower  edge  it 
splits  to  cover  the  pectoralis  minor  muscle  and  forms  a  sheath  for  it.  As  the  axillary 
fascia  approaches  the  apex  of  the  axilla  where  the  superficial  vessels  enter,  it  becomes 
cribriform  in  character,  the  fascia  itself  being  wide-meshed  and  containing  fat  in  the 
interstices.  If  the  handle  of  the  scalpel  is  inserted  in  the  apex  of  the  axilla  and 
worked  backward  and  forward  two  arches  of  fascia  are  readily  formed,  one  convex 
toward  the  chest,  and  called  the  "  Achselbogen,"  and  the  other  convex  toward  the 
arm,  called  the  "Armbogen"  (Langer,  Oester.  med.   IVoch.,  1846,  Nos.  15  and  16). 

The  fascia  on  the  superficial  surface  of  the  pectoralis  minor  is  called  the  clavi- 
pedoral fascia.     At  the  upper  or  inner  border  of  the  pectoralis  minor  it  is  continuous 


THE   AXILLA.  257 

with  the  costocoracoid  membrane  which  goes  up  to  the  clavicle,  where  it  splits  to 
enclose  the  subclavius  muscle  and  to  be  attached  to  the  anterior  and  posterior  borders 
of  the  clavicle.  The  upper  portion  of  this  costocoracoid  membrane  is  thickened  and 
forms  a  firm  band  which  runs  from  the  coracoid  process  to  the  cartilage  of  the  first 
rib,  and  is  called  the  costocoracoid  ligament. 

Between  this  ligament  above  and  the  upper  edge  of  the  pectoralis  minor  below, 
and  piercing  the  costocoracoid  membrane,  are  the  acromiothoracic  artery  and  vein, 
the  cephalic  vein,  the  superior  thoracic  artery,  external  anterior  thoracic  nerve,  and  a 
few  lymphatics  derived  from  the  breast.  The  superior  thoracic  artery  is  often  a 
branch  of  the  acromiothoracic  and  passes  behind  the  vein  to  supply  the  serratus 
anterior  and  intercostal  muscles  and  side  of  the  chest. 

The  fascia  on  the  under  surface  of  the  pectoralis  minor  unites  with  the  layer  on 
its  upper  surface,  and  passes  upward  to  the  coracoid  process  and  is  reflected  onto  the 


Pectoralis  major 

\  4P^'^", 

^  Axillary  arch 


*'^, 


fl®**' 


Intercostohumeral  nerve 


Teres  major  and  latissimus  dorsi 


Fig.  269. — Axillary  fascia.  At  the  apex  of  the  axilla  the  fascia  is  almost  lacking,  forming  a  curved  arch  on 
the  side  toward  the  chest,  called  the  axillary  arch  or  "  Achselbogen."  The  curved  edge  toward  the  arm,  less  dis- 
tinct than  that  toward  the  chest,  is  called  the  "  Armbogen." 

vessels  to  aid  in  forming  their  sheath.      It  is  continuous  with  the  fascia  on  the  under 
surface  of  the  subclavius  muscle  and  the  deep  fascia  of  the  neck. 

This  portion  of  the  fascia  is  not  sufficiently  strong  to  form  an  absolute  barrier 
between  the  neck  and  axilla,  consequently  abscesses  forming  in  the  neck  will  break 
through  it  and  passing  under  the  clavicle  appear  in  the  axilla,  and  abscesses  starting 
in  the  axilla  may  burrow  under  the  clavicle  and  up  beneath  the  deep  fascia  of  the  neck. 

THE  AXILLARY  VESSELS. 

The  axillary  artery  and  vein  are  both  important.  The  avoidance  of  hemorrhage 
in  operations  in  this  locality  requires  skill  and  knowledge,  and  venous  bleeding  is 
more  apt  to  be  troublesome  than  arterial.  Wounds  of  the  vessels,  whether  artery 
or  vein,  of  those  portions  of  the  body  like  the  axillae,  groins,  or  base  of  the  neck  are 
particularly  dangerous;  the  blood  current  is  both  large  and  rapid. 

The  axillary  vein  drains  the  whole  upper  extremity  and  part  of  the  chest,  while 
the  axillary  artery  carries  all  the  blood  going  to  those  parts.  The  veins  being  so 
much  weaker  and  thinner  walled  than  the  arteries  is  the  reason  of  their  being  more 
frequently  injured.  Ligation  of  the  artery,  or  vein,  or  both,  may  cause  gangrene  of 
the  extremity  and  require  amputation. 

The  Axillary  Artery. — The  axillary  artery  begins  at  the  lower  border  of  the 
first  rib  and  ends  opposite  the  lower  border  of  the  folds  of  the  axilla  (teres  major). 
If  the  arm  is  lying  by  the  side  of  the  body  the  artery  describes  a  curve  with  its 
17 


258 


APPLIED    ANATOMY. 


convexity  outward.  If  the  arm  is  placed  straij^ht  out  away  from  the  body,  the  artery 
is  straight.  If  the  arm  is  abducted  above  the  level  of  the  shoulder,  the  artery  again 
becomes  curved  but  with  its  convexity  downward. 

The  line  of  the  artery  is  straight  only  when  the  arm  is  out  from  the  body,  when 
its  course  is  represented  by  a  line  drawn  from  the  middle  of  the  clavicle  to  the 
anterior  surface  of  the  elbow,  midway  between  the  two  condyles.  It  passes  down 
along  the  inner  side  of  tht  coracoid  process  and  the  coracobrachialis  muscle  about  at 
the  junction  of  the  anterior  and  middle  thirds  of  the  axilla.  It  is  divided  into  three 
parts  by  the  pectoralis  minor  muscle  (Fig.  270). 

First  Portion. — The  first  portion  of  the  axillary  is  usually  stated  to  be  2.5  cm. 
(i  in.)  in  length,  and  for  surgical  purposes  we  may  accept  this  as  a  working  basis. 

A.  H.  Young  has  pointed  out  that,  with  the  arm  out  from  the  body,  the  upper 
border  of  the  pectoralis  minor  is  nearly  or  quite  level  with  the  lower  border  of 
the  first  rib,  but  the  muscle  leaves  the  side  of  the  chest  to  go  to  the  coracoid 
process  and  that  makes  an  interspace,  more  than  2. 5  cm.  long,  above  its  upper  edge 

Pectoralis  major 
Deltoid 


Biceps 


Coracobrachialis 
Groove  for  axillary  vessels  and  nerves 
Long  head  of  triceps  muscle 

Teres  major  and  latissimus  dorsi  muscles 


Fig.  270. — Line  indicating  the  course  of  the  axillary  artery. 

and  between  it  and  the  lower  edge  of  the  subclavius  muscle,  in  which  the  artery  can 
be  ligated.  In  the  first  portion  the  axillary  artery  above  the  pectoralis  minor  lies  too 
deep  to  be  compressed,  being  on  a  lower  level  than  the  pectoralis  major,  therefore 
it  is  better  to  compress  the  subclavian  above  the  clavicle. 

Branches. — The  first  portion  of  the  axillary  gives  of?  two  branches,  the  superior 
thoracic  and  the  acromiothoracic  (thoraco-acromialis)  (Fig.  271). 

The  superior  thoracic  comes  of?  posteriorly  and  winds  around  behind  the  axillary 
vein  to  supply  the  under  surface  of  the  pectoralis  minor,  intercostal  muscles,  serratus 
anterior,  and  side  of  the  chest.      It  is  a  small  vessel. 

The  acromiothoracic  (thoraco-acro?nialis)  is  a  short  large  trunk  which  comes  of? 
anteriorly,  winding  around  the  edge  of  the  pectoralis  minor  and  piercing  the  costo- 
coracoid  membrane  to  divide  into  four  branches:  an  acromial,  to  the  acromion 
process;  a  humeral,  which  follows  the  cephalic  vein  between  the  deltoid  and  pecto- 
ralis major;  a  pectoral,  which  supplies  the  under  surface  of  the  pectoralis  major  and 
gives  branches  to  the  mammary  gland;  and  a  clavicular,  to  supply  the  subclavius 
muscle. 

Relations. — Posteriorly^  the  artery  lies  on  the  first  intercostal  space  and 
muscle,  the  second  and  part  of  the  third  serrations  of  the  serratus  anterior,  the  pos- 
terior thoracic  nerve  (or  external  respiratory  of  Bell),  and  the  internal  anterior 
thoracic  nerve  to  the  pectoralis  minor  and  major. 


THE   AXILLA. 


259 


Internally. — ^To  the  inner  side  of  the  artery  and  somewhat  anteriorly  is  the 
axillary  vein;  between  the  two  runs  the  internal  anterior  thoracic  nerve.  As  the 
artery  and  vein  ascend  they  become  separated,  the  artery  to  pass  behind  and  the 
vein  in  front  of  the  scalenus  anterior  muscle. 

Externally.  —  To  the  outer  side  and  above  the  artery  lie  the  cords  of  the 
brachial  plexus. 

Anteriorly. — In  front  of  the  artery  are  the  skin  and  superficial  fascia,  the  edge 
of  the  pectoralis  major  muscle  and  fascia  covering  it,  the  costocoracoid  membrane 
pierced  by  the  acromiothoracic  artery,  cephalic  vein,  and  external  anterior  thoracic 
nerve,  which  goes  to  supply  the  pectoralis  major  muscle. 

Ligation  of  the  First  Portion  of  the  Axillary  Artery. — The  artery  lies 
deep  in  the  infraclavicular  triangle,  between  the  pectoralis  major  and  deltoid  muscles. 
It  can  be  approached  by  either  a  transverse  or  a  longitudinal  incision.  If  the  former 
is  used  it  should  be  made  through  the  skin  only,  immediately  below  the  clavicle, 
reaching  from  just  outside  the  sternoclavicular  joint  to  the  coracoid  process. 

The  pectoralis  major  is  detached  from  the  clavicle  and  pushed  downward,  it 
arises  from  its  inner  half.      This  exposes  the  costocoracoid  membrane.      At  the  outer 


Pectoralis  minor 


Pectoralis  major 


Biceps 


Pectnralis  major  muscle 
Superior  thoracic 


Acromiothoracic 


- —  Long  thoracic 


•Alar  thoracic 


Subscapular 

.,  ,     \  Posterior  circumflex 

Anterior  V  .     \ 

circumflex        N^     Latissimus  dorsi 
Triceps 
Fig.  271. — Diagrammatic  view  of  axillary  artery  and  its  branches. 

angle  of  the  wound  the  cephalic  vein  and  acromiothoracic  artery  are  to  be  found. 

The  deltoid  muscle  is  to  be  detached  or  pushed  outward  to  expose  the  coracoid 
process,  this  being  recognized,  the  costocoracoid  membrane  is  to  be  opened  to  its 
inner  side,  between  it  and  the  cephalic  vein.  The  acromiothoracic  artery  if  isolated 
will  lead  to  the  artery,  while  the  cephalic  vein  goes  direct  to  the  subclavian  vein. 
The  vein  and  costocoracoid  membrane  are  closely  united  and  great  care  is  necessary 
to  avoid  wounding  the  former  in  opening  the  latter.  The  cords  of  the  brachial 
plexus  are  to  the  outer  side  of  the  artery  and  care  is  to  be  exercised  not  to  mistake 
one  of  them  for  the  artery.  As  the  vein  is  the  most  dangerous  structure,  it  is  to  be 
displaced  inward  and  the  aneurism  needle  passed  between  it  and  the  artery  from 
within  outward. 

As  the  external  anterior  thoracic  nerve  is  a  nerve  of  motion  supplying  the 
pectoralis  major  muscle,  if  it  is  seen  it  should  be  avoided  and  not  injured. 

If  it  is  desired  to  use  a  longitudinal  instead  of  transverse  incision,  it  should  com- 
mence just  outside  the  middle  of  the  clavicle  and  follow  the  groove  between  the  deltoid 
and  pectoralis  major  muscles  downward  for  10  cm.  (6  in. ).  Great  care  is  then  neces- 
sary to  avoid  wounding  the  cephalic  vein  and  acromiothoracic  artery,  which  lie  in  this 
groove. 

If  sufficient  exposure  is  not  given  by  a  single  straight  incision  it  can  be  supple- 
mented by  one  detaching  the  pectoralis  major  from  the  clavicle. 


26o 


APPLIED    ANATOMY. 


Second  Portion. — The  second  portion  of  the  axillary  lies  beneath  the  pecto- 
ralis  minor  muscle.  It  is  3  cm.  ( 1 1^  in.  )  long  and  while  never  ligated  at  this  point  it  is 
nevertheless  frequently  exposed  while  clearing  out  the  axilla  for  malignant  growths  of 
the  breast.  Owing  to  its  being  covered  by  the  pectoralis  minor  and  major  muscles 
the  artery  cannot  be  compressed  at  this  point  in  its  course. 

Branches. — Its  branches  are  the  alar  thoracic  and  long  thoracic.  The  alar  tho- 
racic are  small  branches  of  little  importance  supplying  the  fat  and  glands  of  the 
axilla. 

The  long  thoracic  or  external  mammary  is  of  considerable  importance  on  account 
of  its  size  and  because  it  is  encountered  in  operations  on  the  breast  and  axilla.  It 
passes  down  along  the  lower  (outer)  border  of  the  pectoralis  minor,  giving  branches 
to  it  and  the  pectoralis  major;  some  branches  go  to  the  axilla  and  serratus  anterior, 
and  others,  which  may  be  of  considerable  size  in  the  female,  wind  around  the  lower 
portion  of  the  pectoralis  major  or  pierce  it  to  supply  the  mammary  gland.      Posterior 


Pectoralis  major 


Superior  thoracic  artery 


Acromiothoracic  arte: 

Coracoid  process- 

Peclotalis  minor  muscle 

Axillary  artery. 

Axillary  vein 

Alar  thoracic  artery 

Long  head  of  bicepi 

Coracobrachialis  and  short 

head  of  biceps 

Musculocutaneous  nerve 

Long  thoracic  artery. 
Anterior  circumflex  artery 
Subscapular  artery 
Posterior  circumflex  artery 
Pectoralis  major  muscle 
Median  nerve 

Internal  cutaneous  nerve 

Ulnar  ner\'e 

Lesser  internal 

cutaneous  nerve 


Pectoralis  minor 


I^tissimus  dorsi 
Teres  major  muscle 
Intercostohumeral  nerve 


Fig.  272. — Dissection  of  the  axilla. 


to  it  is  the  long  or  posterior  thoracic  nerve,  or  external  respiratory  nerve  of  Bell, 
going  to  supply  the  serratus  anterior  muscle  (Fig.  272). 

Relations.  — Anteriorly  is  the  pectoralis  minor  muscle,  superficial  to  which  is  the 
pectoralis  major  and  skin.  Posteriorly  lie  the  posterior  cord  of  the  brachial  plexus, 
the  fat  of  the  axilla,  and  the  subscapularis  muscle;  intcj'nally  is  the  axillary  vein,  with 
the  inner  cord  of  the  brachial  plexus  separating  the  two.  Externally  is  the  outer 
cord  of  the  plexus  and  farther  out  is  the  coracoid  process. 

Third  Portion. — This  is  about  7.5  cm.  (3  in.)  long  and  runs  from  the  lower 
border  of  the  pectoralis  minor  to  the  lower  border  of  the  teres  major.  Its  upper 
portion  is  under  the  pectoralis  major  but  its  lower  portion  is  subcutaneous  because 
the  teres  major,  forming  the  edge  of  the  posterior  fold  of  the  axilla,  extends  lower 
than  the  anterior  fold.  It  is  here  that  the  axillary  artery  is  most  easily  reached  and 
most  often  ligated. 

Branches. — It  gives  of?  three  branches,  the  subscapular,  the  anterior  circumflex, 
and  the  posterior  circumflex. 

The  subscapular  artery  is  of  considerable  practical  importance;  it  is  the  largest 
branch  of  the  axillary  and  is  given  off  opposite  the  lower  border  of  the  subscapularis 
muscle.      It  follows  the  lower  edge  of  this  muscle  down  the  axillary  or  outer  border 


THE  AXILLA. 


261 


of  the  scapula  to  its  angle,  where  it  anastomoses  with  the  posterior  scapular,  one  of 
the  terminal  branches  of  the  transverse  cervical  from  the  thyroid  axis. 

Four  centimetres  ( I  y^  in. )  from  its  origin  the  subscapular  gives  off  the  dorsalis 
scapiil(S,  which  is  as  large  or  larger  than  the  continuation  of  the  artery  downward. 
The  position  of  this  artery  should  be  borne  in  mind  in  operating.  It  winds  around 
the  outer  edge  of  the  scapula  between  it  and  the  teres  minor  muscle  to  supply  the 
muscles  posteriorly.  The  subscapular  artery  is  accompanied  by  the  long  subscapular 
nerve  to  its  inner  side.  (The  first  or  short  subscapular  nerve  supplies  the  subscapu- 
laris  muscle,  the  second  supplies  the  teres  major  and  the  third  or  long  subscapular 
supplies  the  latissimus  dorsi  muscle. ) 

The  posterior  axillary  chain  of  lymph-nodes  accompanies  the  subscapular  artery, 
hence  it  is  involved  in  operations  for  their  removal.  The  point  at  which  the  dorsalis 
scapulae  winds  aroimd  the  axillary  border  of  the  bone  is  at  or  just  above  the  level  of  the 
middle  of  the  deltoid  muscle  and  below  the  level  of  the  posterior  circumflex  artery. 

The  anterior  circiunflex  artery  is  comparatively  insignificant.  It  winds  ante- 
riorly around  the  surgical  neck  of  the  humerus  beneath  the  coracobrachialis  muscle 
and  both  heads  of  the  biceps  and  gives  off  an  ascending  bicipital  branch  which  ascends 
in  the  bicipital  groove  and  a  small  descending  branch  to  the  tendon  of  the  pectoralis 


Coracobrachialis  muscle 


Median  nerve 


Axillary  artery 
Ulnar  nerve 
Internal  cutaneous  nerve 


Fig.  273. — Ligation  of  the  third  portion  of  the  axillary  artery. 


major.  As  pointed  out  by  Walsham,  the  anterior  circumflex  artery  on  account  of 
the  closeness  with  which  it  hugs  the  bone  may  be  difficult  to  secure  if  wounded  in  the 
operation  of  resection  of  the  humerus. 

The  posterior  circumflex  artery  is  much  larger  than  the  anterior.  It  runs  around 
the  surgical  neck  posteriorly,  below  the  teres  minor,  above  the  teres  major,  and 
between  the  long  head  of  the  triceps  and  the  humerus.  It  is  accompanied  by  the 
circumflex  (axillary)  nerve  and  they  run  transversely  around  beneath  the  deltoid 
muscle  on  a  level  with  the  junction  of  its  upper  and  middle  thirds.  It  is  to  avoid 
wounding  these  two  important  structures  that  the  operation  of  resection  is  done 
anteriorly  instead  of  posteriorly.  Being  covered  only  by  the  skin  of  the  axilla  and  the 
superficial  and  deep  fascias,  it  can  readily  be  compressed  by  pressure  directed  out- 
wardly against  the  humerus  along  the  inner  edge  of  the  coracobrachialis  muscle. 

Relations. — Posteriorly  the  third  portion  of  the  axillary  artery  lies  on  the  sub- 
scapularis,  the  latissimus  dorsi,  and  teres  major  muscles,  with  the  musculospiral  and 
circumflex  (axillary)  nerves  between  the  muscles  and  the  artery. 

Anteriorly  it  is  covered  by  the  skin  and  fascia,  the  pectoralis  major  above,  and 
deep  fascia  of  the  arm  below.  The  inner  root  of  the  median  nerve  crosses  it  and 
sometimes  the  outer  vena  comes. 


262 


APPLIED    ANATOMY. 


Acromiothoracic 


Posterior  circumflex 
Anterior  circumflex 
Subscapular 

Alar  thoracic 


Externally  is  the  coracobrachial  muscle  (which  partly  overlaps  it  and  forms  its 

guide),  the  main  trunk  and  outer  head  of  the  median,  and  the  musculocutaneous  nerves. 

Inteffially  is  the  axillary  vein  with  the  ulnar  ner\'e  between  it  and  the  artery. 

The  internal  and  lesser  internal  cutaneous  nerves  also  lie  to  its  inner  side  with  the 

former  the  more  anterior. 

Ligation  of  the  Third  Portion  of  the  Axillary  Artery. — The  arm  being 
placed  out  from  the  body,  palm  upward,  the  incision  for  ligating  the  axillary  artery  in 
the  third  portion  of  its  course  is  laid  along  the  inner  border  of  the  coracobrachial 
muscle,  at  about  the  junction  of  the  anterior  and  middle  thirds  of  the  axilla  and  on  a 
line  joining  the  middle  of  the  clavicle  and  a  point  at  the  bend  of  the  elbow  midway 
between  the  two  condyles  of  the  humerus. 

The  middle  of  the  incision  should  be  just  above  the  lower  edge  of  the  folds  of 
the  axilla.     The  deep  fascia  having  been  opened,  the  coracobrachial  muscle  with  the 

musculocutaneous  nerve  piercing  it  is 
pulled  outward.  Lying  on  the  artery 
to  its  outer  side  is  the  median  nerve; 
it  is  to  be  drawn  outward.  To  the 
inner  side  lies  the  axillary  vein  with 
the  ulnar  nerve  beneath  it  and  the 
internal  cutaneous  nerve  (cutaneus 
antebrachii  medialis)  in  front  of  it 
close  to  the  artery. 

The  needle  is  passed  from  within 
outward.  The  artery  at  this  point  may 
be  crossed  by  some  muscular  fibres 
coming  from  the  latissimus  dorsi  and 
crossing  the  axilla.  The  axillary  vein 
is  the  continuation  of  the  basilic  from 
the  lower  border  of  the  teres  major 
upward. 

Of  the  two  venae  comites  of  the 
brachial  artery  the  inner  one  blends 
with  the  basilic  at  the  lower  border 
of  the  teres  major;  the  outer  one 
crosses  the  artery  to  empty  into  the 
axillary  vein  on  the  opposite  side. 

The  axillary  vein  receives  the 
subscapular,  circumflex,  long  thoracic, 
acromiothoracic,  alar,  and  cephalic, 
and  contains  a  pair  of  valves  opposite  the  lower  border  of  the  subscapularis  muscle. 
Collateral  Circulation  after  Ligature  of  the  Axillary  Artery. — If  the 
first  portion  of  the  axillary  is  tied,  the  acromiothoracic  artery  comes  off  so  low  down 
(under  the  edge  of  the  pectoralis  minor  muscle  almost)  that  the  ligature  is  placed 
above  it,  in  which  case  the  collateral  circulation  is  similar  to  that  of  the  subclavian 
(see  page  149).  The  second  portion  of  the  axillary,  lying  beneath  the  pectoralis 
minor,  is  not  subject  to  ligation.  In  the  third  portion  the  subscapular  and  anterior 
and  posterior  circumflex  arteries  come  off  so  close  together  that  the  ligature  will  be 
placed  either  just  below  or  just  above  them  (Fig.  274). 

If  below,  then  the  collateral  circulation  will  be  between  them  above  and  the 
superior  profunda  below.  If  above  the  subscapular,  then  the  anastomosis  would  be 
as  follows: 

Proximal  Vessels.  Distal  Vessels. 

Acromiothoracic,  acromial  branch with  anterior  and  posterior  circumflex 

Acromiothoracic,  humeral  branch with  anterior  and  posterior  circumflex 

Acromiothoracic,  pectoral  branch with  subscapular 

Long  thoracic  branch with  subscapular 

Alar  thoracic  branch with  subscapular 

Posterior  scapular  (branch  of  trans,  cervical)  with  subscapular  and  dorsalis  scapulae 

Suprascapular      with  dorsalis  scapulae  and   posterior 

circumflex 


Superior  profunda  (arteria 
profunda  brachii) 


Brachial  artery 


Fig. 


-Collateral  circulation  after  ligation  of  the  third 
portion  of  the  axillary  artery. 


THE  AXILLA. 


263 


Lymphatics  of  the  Axilla. — There  are  two  sets  of  lymphatic  nodes  in  the 
axillary  region,  the  axillary  nodes  proper  and  the  subclavian  nodes. 

The  number  of  the  nodes  varies  from  about  ten  or  twelve  to  twenty  or  more. 
When  enlarged  they  are  readily  seen,  but  after  the  surgeon  has  carefully  dissected 
away  all  the  nodes  he  can  possibly  find  disease  may  subsequently  reveal  the  exist- 
ence of  others.  Hence  it  is  impossible  ever  to  be  absolutely  sure  that  all  nodes  have 
been  removed. 

The  subclavian  nodes,  about  two  or  three  in  number,  lie  in  the  infraclavicular 
triangle  between  the  pectoraUs  major  and  deltoid  muscles  and  on  the  front  of  the 
subclavian  vein  above  the  pectoralis  minor  muscle.  They  receive  radicles  from  the 
mammary  gland  as  well  as  from  the  axillary  groups. 

The  axillary  nodes  proper  are  composed  of  three  sets,  humeral  or  external, 
thoracic  or  anterior,  and  scapular  or  posterior,  accompanying  the  three  vessels, 
axillary,  long  thoracic,  and  subscapular. 

The  humeral  set,  perhaps  eight  or  nine,  accompany  the  axillary  artery  and 
vein  and  lie  along  them  and  in  the  axillary  fat.      They  receive  mainly  the  lymphatics 


Deltopectoral  node 


Brachial  node 


Subscapular  node 


Anterior  pectoral  node y- 

Vessel  passing  to  anterior 

pectoral  node 


Inferior  pectoral  node 


Subclavian  node 


Vessel  passing  to 
subclavian  node 


Intermediate  node 


Subareolar  plexus 
over  mammary 
gland 


Fig.  275. — Lymphatics  of  mammary  gland,  and  axillary  nodes.     (Poirier  and  Cun^o.) 

from  the  arm.  They  can  often  be  pared  off  the  vessels  with  ease,  but  sometimes 
are  so  firmly  attached  that  the  vessels  are  injured  in  their  removal. 

The  anterior  or  thoracic  set  accompany  the  long  thoracic  artery  along  the  lower 
border  of  the  pectoral  muscles.  They  are  not  so  numerous  as  the  humeral  set, 
perhaps  four  or  five  in  number,  and  drain  the  anterior  upper  half  of  the  chest  above 
the  umbilicus,  including  the  mammary  gland  (Fig.  275). 

The  posterior  or  scapular  set  accompany  the  subscapular  artery  along  the  pos- 
terior portion  of  the  axilla.  They  are  about  as  numerous  as  the  anterior  set  and 
drain  the  upper  posterior  portion  of  the  chest,  the  scapula  and  lower  portion  of  the  neck. 

The  lymphatics  of  the  middle  and  lower  portion  of  the  back  as  low  down  as  the 
umbilicus  (3  to  4  cm.  above  the  iliac  crest)  also  drain  into  the  axilla. 

These  lymphatic  nodes  communicate  with  one  another,  so  that  it  does  not  of 
necessity  follow  that  if  the  part  ordinarily  drained  by  a  certain  set  is  affected  the 
nearest  nodes  will  be  involved.  It  usually  is  so,  but  not  always.  The  infection  may 
pass  by  or  through  one  set  of  nodes  and  involve  a  neighboring  communicating  set. 
It  happens  in  carcinoma  of  the  breast  that  sometimes  the  posterior  or  scapular  set  are 


264 


APPLIED    ANATOMY. 


involved  and  the  anterior  or  thoracic  set  escape.  This  has  already  been  alluded  to 
in  the  section  on  the  mammary  gland  (see  page  184).  These  three  sets  drain  into 
the  subclavian  nodes  and  then  empty  into  the  subclavian  vein  near  its  junction  with 
the  jugular. 

Abscess  of  the  Axilla. — Pus  forms  in  the  axillary  region  from  ordinary  pyo- 
genic organisms  which  may  or  may  not  be  associated  with  specific  organisms  like 
the  tubercle  bacillus.      Abscesses  may  be  either  superficial  or  deep. 

The  skm  of  the  axilla  is  thin,  loose,  and  abundantly  supplied  with  sebaceous 
glands  connected  with  the  hair-follicles  and  sweat-glands.  These  glands  are  in  the 
deeper  layer  of  the  skin  and  are  superficial  to  the  axillary  fascia,  hence  abscesses 
originating  from  them  tend  to  break  externally;  usually  they  do  not  become  large 
nor  extend  deep  into  the  axilla. 

Abscesses  originating  from  the  lymphatics,  on  the  contrary,  may  be  either  deep  in 
the  axilla  along  the  axillary,  pectoral,  or  subscapular  vessels,  or  they  may  be  in  the 
axillary  fat  and  tend  to  point  toward  the  skin.  If  the  lymphatics  along  the  axillary 
vessels  are  the  point  of  origin,  the  abscess  may  follow  them  down  under  the  deep 
fascia  to  the  elbow.  If  the  nodes  high  up  are  involved,  the  abscess  may  work  up 
under  the  clavicle  into  the  neck.     If,  however,  the  nodes  near  the  apex  of  the  axilla 


Fig.  276. — Subpectoral  abscess. 

form  the  starting-point  then  the  abscess  bulges  through  the  cribriform  portion  of  the 
axillary  fascia  (between  the  "  Armbogen  "  and  "  Achselbogen  " )  into  the  axilla 
and  tends  to  discharge  through  the  skin.  Abscesses  originating  in  the  pectoral 
group  of  lymphatics  point  at  the  lower  margin  of  the  anterior  axillary  fold.  The 
attachment  of  the  serratus  anterior  to  the  side  of  the  chest  prevents  them  from  work- 
ing towards  the  back. 

Abscesses  involving  the  subclavian  nodes  may  cause  a  siibpedoi'al  abscess  (Fig. 
276).  The  pus  collects  superficial  to  the  costocoracoid  membrane  and  clavipectoral 
fascia  and  pushes  the  pectoralis  major  muscle  outward,  forming  a  large  rounded 
prominence  below  the  inner  half  of  the  clavicle.  The  pus  cannot  extend  upward  or 
toward  the  median  line  on  account  of  the  attachment  of  the  pectoralis  major  muscle. 
It  can  burrow  through  the  intercostal  spaces  and  involve  the  pleural  cavity,  or  break 
through  the  fibres  of  the  pectoralis  major  anteriorly  or  between  the  pectoralis  major 
and  deltoid,  or,  as  is  most  commonly  the  case,  work  its  way  under  the  pectoralis 
major  muscle,  over  the  pectoralis  minor,  until  it  reaches  the  border  of  the  pectoralis 
major  at  the  anterior  fold  of  the  axilla. 

In  emptying  these  abscesses  an  incision  is  to  be  made  along  the  anterior  axillary 
fold  and  a  tube  introduced  beneath  the  pectoralis  major. 

Incision  for  Axillary  Abscess. — In  opening  an  axillary  abscess  one  should  bear  in 
mind  that  the  important  veins  and  nerves  accompany  the  arteries  and  that  the  arteries 
lie  in  three  places,  viz. ,  externally  along  the  humerus,  anteriorly  along  the  edge  of  the 
pectoral  muscles,  and  posteriorly  along  the  edge  of  the  scapula ;  therefore  these  three 
localities  are  to  be  avoided  and  an  incision  made  in  the  middle  of  the  axilla  and  short 
enough  not  to  endanger  the  brachial  vessels  on  the  outside  or  the  long  thoracic  or 
subscapular  on  the  inside  near  the  chest-wall. 

The  incision  may  divide  the  skin  and  if  desired  the  deeper  structures  can  be 
parted  by  introducing  a  closed  haemostatic  forceps  and  separating  its  jaws. 


THE   AXILLA.  265 

Axillary  abscesses,  if  of  slow  formation  and  unopened,  tend  to  burrow  and  follow 
the  vessels  upward  beneath  the  clavicle  and  appear  in  the  supraclavicular  space  beneath 
the  deep  cervical  fascia,  and  they  may  even  enter  the  superior  mediastinum.  They 
may  also  descend  the  arm  under  the  fascia  covering  the  coracobrachialis  muscle. 

Axillary  Tumors. — Tumors  of  the  axilla  are  almost  always  due  to  involvement 
of  the  lymph-nodes.  They  may  be  either  benign  and  inflammatory  in  character,  form- 
ing the  ordinary  axillary  adenitis,  or  tuberculous,  or  they  may  be  malignant.  As 
they  are  due  to  disease  of  the  lymph-nodes,  the  parts  which  the  glands  drain  should 
be  searched  for  the  starting-point  of  the  affection.  Aneurism  or  abscess  may  be 
mistaken  for  a  new  growth  and  an  inflamed  aneurism  may  readily  be  thought  to  be 
an  abscess. 

The  excision  of  axillary  tumors  is  difficult.  If  the  tumor  is  of  an  inflammatory 
origin  it  may  be  closely  adherent  to  the  veins  or  arteries  or  nerves,  and  the  same  con- 
dition may  exist  in  malignant  cases. 

The  blood  supply  of  the  axilla  is  so  free  that  nothing  is  to  be  gained  by  saving 
small  vessels,  therefore  in  paring  a  tumor  off  the  axillary  vessels  the  various  small 
branches  are  ligated  and  divided  and  the  main  vessels  left  bare.  This  applies  to  the 
veins  as  well  as  the  arteries. 

The  subscapular  artery  is  so  large  that  it  is  often  allowed  to  remain.  When 
working  in  the  posterior  portion  of  the  axilla  it  is  to  be  remembered  that  the  pos- 
terior circumflex  artery  is  opposite  the  surgical  neck  of  the  humerus,  above  the 
tendon  of  the  latissimus  dorsi  muscle,  and  that  the  subscapular  artery  is  on  the 
opposite  side  of  the  axillary  artery  a  little  higher  up.  The  large  subscapular  vein 
will  bleed  profusely  if  wounded  and  it  should  be  looked  for  at  the  axillary  border  of 
the  scapula  below  the  subscapularis  muscle. 

Wounds  of  the  axillary  vein  are  particularly  dangerous  on  account  of  the  admis- 
sion of  air.  The  attachment  of  the  vein  to  the  under  side  of  the  pectoralis  minor  and 
costocoracoid  membrane  keeps  it  from  collapsing;  hence  the  danger. 

Nerves  of  the  Axilla. — The  brachial  plexus  is  above  the  first  portion  of  the 
axillary  artery.  In  the  second  portion  one  cord  is  to  the  inner  side,  one  to  the 
outer,  and  one  behind.  In  the  third  portion  the  median  nerve  is  anterior  and  a  little 
to  the  outer  side  of  the  artery,  being  formed  by  two  roots,  one  from  the  inner  and 
the  other  from  the  outer  cord  of  the  brachial  plexus. 

The  musculocutaneous  nerve  is  to  the  outer  side  of  the  artery,  leaving  the  outer 
cord  to  enter  the  coracobrachialis  muscle.  The  ulnar,  internal  cutayieous  {cutaneus 
antebrachii  medialis),  and  lesser  internal  cutaneous  {czitaneus  brachii  medialis)  come 
from  the  inner  cord  and  lie  to  the  inner  side  of  the  artery.  From  the  posterior  cord 
come  the  axillary  {circumflex^  and  radial  (^musculo spiral^  nerves.  On  the  inner  wall 
of  the  axilla  behind  the  long  thoracic  artery  is  the  N.  thoracalis  longus  (long  thoracic, 
or  external  respiratory  nerve  of  Bell);  it  is  a  motor  nerve  and  supplies  the  serratus 
anterior  (magnus)  muscle,  hence  it  is  not  to  be  injured  in  clearing  out  the  axilla. 

Still  farther  posteriorly,  accompanying  the  subscapular  artery,  is  the  thoraco- 
dorsalis  or  long  subscapular  nerve.  It  also  is  a  motor  nerve  supplying  the  latissimus 
dorsi  muscle;  therefore  it  is  to  be  spared. 

Crossing  the  axilla  from  the  second  intercostal  space  to  anastomose  with  the 
cutaneus  brachii  medialis  nerve  is  the  intercostobrachial  {humeral^  nerve.  It  is  a 
nerve  of  sensation  and  need  not  be  spared.  Sometimes  another  branch  from  the 
third  intercostal  nerve  also  crosses  the  axilla;  it  is  also  sensory  and  can  be  cut  away. 

As  the  axillary  {circumflex)  nerve  normally  winds  around  the  surgical  neck 
of  the  humerus,  when  luxation  occurs  it  is  stretched  over  the  head  and  paralysis  of 
the  deltoid  may  ensue. 

The  various  nerves  of  the  brachial  plexus  are  often  injured  by  pressure  resulting 
from  the  use  of  crutches  ("crutch  palsy").  It  is  liable  to  affect  any  or  several  of 
the  nerves,  the  radial  (musculospiral)  probably  the  most  frequently.  Neuritis  is 
common  and,  as  in  injuries,  the  nerves  affected  are  recognized  by  the  motor  or 
sensory  symptoms  produced. 


266 


APPLIED    ANATOMY. 


THE  ARM. 

The  arm — or  upper  arm — is  formed  by  a  single  bone  surrounded  by  muscles, 
which,  with  the  exception  of  the  biceps,  are  attached  to  it.  The  main  vessels  and 
most  of  the  important  nerves  run  down  its  inner  side.  It  receives  from  the  trunk  the 
insertions  of  the  muscles  which  move  it,  and  gives  origin  to  the  muscles  which  move 


Anatomical  nee 


Supraspinatus. 

Greater  tuberosity. 
Lesser  tuberosity 

Bicipital  groove 

Surgical  neck 


Pectoralis  major, 


Brachioradialis 


Extensor  carpi 
radialis  longior 


Radial  fossa 


Teres  major 


— \— Rubscapularis 


Anatomical 
Latissi-  neck 

mus  dorsi 


Capitellu 


Trochlea 


Olecranon 
Pronator  fossa 

radii  teres 
Common  flexor 
tendons 

Flexor  carpi 

ulnaris  and 

other  flexors 


Supraspinatus 
Infraspinatus 

Greater  tuberosity 
Teres  minor 


Deltoid 


Brachialis  anticus 
Musculospiral 
(radial)  groove 


Anconeus 


Trochlea 


Fig.  277. — Anterior  surface  of  humerus,  showing 
attachment  of  muscles. 


Fig.  278. — Posterior  surface  of  humerus,  showing 
attachment  of  muscles. 


the  forearm.  It  is  more  subject  to  injury  than  to  disease;  infection,  caries,  and 
rickets  may  attack  the  bone  and  rarely  new  growths  may  occur,  but  its  common 
affections  are  wounds  involving  the  muscles,  blood-vessels,  or  nerves,  and  fractures 
of  the  bone.      Severe  injuries  occasionally  necessitate  amputation. 


THE  ARM.  267 

THE   HUMERUS. 

The  humerus  is  a  long  bone  with  a  large  medullary  cavity.  Its  shaft  is  com- 
posed of  compact  tissue  and  its  ends  of  cancellous  tissue.  In  shape  it  is  like  the 
letter  /,  that  is,  convex  anteriorly  above  and  concave  anteriorly  below.  At  the  mid- 
dle of  the  bone  on  its  external  surface  is  the  rough  deltoid  eminence  for  the  insertion 
of  the  deltoid  muscle. 

Anterior  Surface. — Separating  the  tuberosities  above  and  running  down  the 
anterior  surface  is  the  bicipital  groove.  Its  external  lip  receives  the  insertion  of  the 
pectoralis  major  muscle,  its  inner  lip  and  floor  those  of  the  latissimus  dorsi  above  and 
the  teres  major  below.  On  its  inner  side  at  and  a  little  below  its  middle,  is  the 
insertion  of  the  coracobrachialis  muscle.      On  the  anterior  surface  from  the  deltoid 


Coracoid  process 


Pectoralis  major 


Pectoralis  minor 

Subscapularis 

Ti     ..  y^  /  "^^^^^^^^^^^^^K*^         ^.-^ —  Teres  major 

Pectoralis  major/  ^^^^^^^^^^H^^--^'^ — 

Long  head  of  biceps,^,--'  [J^ 

^         .  ^  ^ .    , ^^^ ^___ Latissimus  dorsi 

Short  head  of  biceps 

Coracobrachialis, 


Inner  head  of  triceps 


Fig.  279. — Muscles  of  the  anterior  and  internal  aspects  of  the  region  of  the  shoulder. 

eminence  to  the  elbow-joint  is  the  origin  of  the  brachialis  anticus;  it  has  two  heads, 
which  embrace  the  insertion  of  the  deltoid,  one  being  in  front  and  the  other  behind 
it  (Fig.  277). 

Posterior  Surface. — On  the  posterior  surface,  running  obliquely  across  the 
bone  downward  and  outward,  below  the  insertion  of  the  deltoid,  is  a  shallow  groove, 
called  the  inusculospiral  groove  {stdciis  radialis).  It  holds  the  musculospiral 
{radial)  nerve  and  the  superior  profunda  artery.  Above  the  groove  and  to  its 
outer  side  is  the  origin  of  the  outer  head  of  the  triceps  extensor  muscle  and  the 
insertion  of  the  deltoid.  To  its  inner  side,  below,  is  the  origin  of  the  inner  head 
of  the  triceps.  Therefore  the  groove  separates  the  inner  head  of  the  triceps  muscle 
from  the  outer  (Fig.  278). 

MUSCLES  OF  THE  ARM. 

In  order  to  operate  intelligently  it  is  necessary  to  know  the  muscles  and  inter- 
spaces, for  the  latter  carry  important  structures.  The  arm  possesses  four  sets  of 
muscles.  One,  an  external  set,  abducts  it,  the  deltoid ;  another,  or  internal  set,  ad- 
ducts  it  (and  rotates  it  inward),  the  pectoraliz  major ,  teres  tnajor,  latissimus  dorsi, 
and  coracobrachialis ;  another,  anterior  set,  flexes  the  forearm,  the  biceps,  and  the 
brachialis  anticus;  and  the  last,  or  posterior  set,  extends  the  forearm,  the  triceps,  with, 
sometimes,  the  subajiconeus  beneath  it. 


268 


APPLIED    ANATOMY. 


The  External,  or  Abductor  Set. 

This  comprises  only  one  muscle,  the  deltoid;  the  supraspinatus  belongs  to  the 
shoulder  region. 

The  deltoid  forms  the  large  rounded  prominence  of  the  shoulder.  At  its 
insertion  the  bone  is  nearest  the  surface  and  can  be  most  readily  felt.  The  posterior 
edge  can  be  plainly  seen  when  contracted  running  upward  and  inward  and  crossing 


Acromion  process 

Coracoid  process 

Deltoid 

Long  head  of  biceps 

Short  head  of  biceps 
Pectoralis  major 

Biceps  (cut  edge) 


Brachialis  anticus. 


Outer  condyle 
Capitellum 


Insertion  of 
biceps  tendon 


Radius 


Subscapularis 


Teres  major 
Latissimus  dorsi 


Coronoid  process  of  ulna 


Fig.  280. — Anterior  view  of  muscles  of  the  arm. 

the  posterior  fold  of  the  axilla  at  right  angles.      Its  anterior  edge  blends  more  or 
less  completely  with  the  pectoralis  major  (Fig.  279). 

The  Internal  Set. 
The  internal  set  includes  the  coracobrachialis,  with  the  short  head  of  the  biceps, 
and  the  pectoralis  major,  teres  major,  and  latissimus  dorsi. 


THE  ARM.  269 

The  coracobrachialis  arises  from  the  coracoid  process  and  tendon  of  the  short 
head  of  the  biceps  and  inserts  on  the  inner  surface  of  the  humerus  for  a  distance  5  to 
7.5  cm.  (2  to  3  in.)  opposite  the  insertion  of  the  deltoid,  but  extending  a  htde  lower. 
In  its  course  from  the  coracoid  process,  in  its  lower  part,  it  is  subcutaneous  and  pro- 
duces a  distinct  muscular  prominence  along  the  anterior  border  of  the  axilla.  It 
occupies  about  one-third  of  the  width  of  the  axilla  and  is  a  guide  to  the  brachial 
artery.  Below  the  edge  of  the  anterior  axillary  fold  it  dips  down  to  insert  into  the 
bone' and  is  covered  by  the  biceps  muscle.  The  inner  edge  of  the  coracobrachialis 
is  continuous  with  the  inner  edge  of  the  biceps.  When  it  contracts  it  adducts  the 
humerus  and  brings  it  forward. 

The  pectoralis  major,  forming  the  anterior  axillary  fold,  inserts  into  the 
external  lip  of  the  bicipital  groove  from  the  greater  tuberosity  above  to  the  insertion 
of  the  deltoid  below.  The  tendon  is  twisted  on  itself  so  that  the  lowest  fibres  at  its 
origin  are  inserted  the  highest,  and  the  highest  in  origin  are  the  lowest  at  their 
insertion. 

The  latissimus  dorsi  and  teres  major  form  the  posterior  axillary  fold  and 
their  manner  of  insertion  resembles  that  of  the  pectoralis  major.      The  tendon  of  the 


Fig.  28 1 . — Rupture  of  the  tendon  of  the  long  head  of  the  biceps  muscle,  producing  a  swelling 
comparatively  low  down. 

latissimus  dorsi  inserts  into  the  bottom  of  the  bicipital  groove  higher  up  than  the 
teres  major.  Hence  near  the  humerus  the  lower  edge  of  the  posterior  axillary  fold 
is  formed  by  the  teres  major  and  its  lower  border  marks  the  lower  limit  of  the  axillary 
and  the  beginning  of  the  brachial  artery. 

As  the  pectoralis  major,  latissimus  dorsi,  and  teres  minor  muscles  insert  on  the 
anterior  surface  of  the  humerus,  they  tend  to  rotate  it  inward  as  well  as  to  adduct  it. 

The  Anterior  Set. 

The  biceps  and  brachialis  anticus  form  the  muscular  mass  on  the  anterior  surface 
of  the  arm. 

The  biceps  has  no  attachment  to  the  humerus.  It  spans  the  bone  and  is 
attached  to  the  scapula  above  and  to  the  radius  and  deep  fascia  of  the  forearm  below. 
In  the  lower  half  of  the  arm  it  lies  on  the  brachialis  anticus.  The  long  head  runs 
up  in  the  bicipital  groove,  and  is  covered  by  the  tendon  of  the  pectoralis  major  up  to 
the  tuberosities,  above  that  by  the  transverse  humeral  ligament  up  to  the  capsule, 
which  it  perforates,  and,  crossing  over  the  head  of  the  humerus,  is  attached  to  the 
upper  edge  of  the  rim  of  the  glenoid  cavity  (Fig.  280). 

The  bicipital  branch  of  the  anterior  circumflex  artery  accompanies  the  tendon 
in  the  bicipital  groove.     This  tendon  is  comparatively  rarely  luxated,  because  it  is 


270 


APPLIED    ANATOMY. 


firmly  held  in  place  by  the  transverse  humeral  ligament.  Pus,  in  finding-  an  exit 
from,  the  joint,  follows  the  long  tendon  of  the  biceps  and  passes  under  the  transverse 
humeral  ligament,  then  beneath  the  tendon  of  the  pectoralis  major  to  appear  on  the 
anterior  aspect  of  the  arm  at  its  lower  border.  Luxation  of  the  tendon  outwardly 
would  be  opposed  by  the  insertion  of  the  pectoralis  major,  therefore  it  is  only  dis- 
placed inwardly.  Rupture  of  the  long  tendon  may  occur  from  violent  muscular  con- 
traction; or,  in  rheumatoid  arthritis  of  the  shoulder,  the  tendon  may  become  partly 
dissolved  and  break.  When  this  occurs  the  belly  of  the  muscle  contracts  and  forms 
a  large  protuberance  on  the  front  of  the  arm  (Fig.  281). 

The  short  head  of  the  biceps  fuses  with  the  coracobrachialis  muscle,  to  be 
attached  with  it  to  the  coracoid  process  on  its  outer  portion.     The  pectoralis  minor  is 

the  third  muscle  attached  to  this  process. 
The  biceps  forms  the  large  muscular 
swell  on  the  front  of  the  arm  between 
the  anterior  fold  of  the  axilla  and  elbow. 
At  its  lower  end  the  biceps  inserts  by  a 
strong  tendon  into  the  posterior  border 
of  the  bicipital  tubercle  of  the  radius. 
An  example  of  its  rupture  is  shown  in 
Fig.  282.  Between  it  and  the  bone  is 
a  bursa,  which  does  not  communicate 
with  the  elbow-joint.  The  bicipital  fas- 
cia is  given  of?  from  the  tendon  and 
passes  downward  and  inward  to  blend 
with  the  deep  fascia  covering  the  flexor 
group  of  muscles.  The  biceps  not  only 
flexes  the  radius  on  the  arm  but  also  acts 
as  a  powerful  supinator. 

The  brachialis  anticus  covers 
the  lower  three-fifths  of  the  humerus 
and  begins  with  two  slips,  one  on  each 
side  of  the  insertion  of  the  deltoid  ten- 
don. It  inserts  into  the  inner  and  lower 
part  of  the  anterior  surface  of  the  coro- 
noid  process  of  the  ulna.  As  the  articu- 
lation of  the  ulna  and  trochlear  surface 
of  the  humerus  is  a  pure  hinge-joint  the 
muscle  acts  solely  as  a  flexor. 

The  Posterior  or  Extensor  Set. 
The  posterior  or  extensor  set  in- 

PiG.  282. — Rupture  of  the  lower  tendon  of  the  biceps.         i    j       ...i      ...   •  j  i.i.  u  „ 

Contraction  of  the  muscle  produces  a  swelling  abnormally      CludCS  the  triCCpS  and  the  SubanCOneOUS, 

high  up  on  the  arm.    (From  a  photograph.)  when  present  as  a  distinct  muscle. 

The  Triceps  Muscle. — The  mus- 
cular mass  on  the  posterior  surface  of  the  arm  is  formed  solely  by  the  triceps  muscle. 
It  arises  by  three  heads  and  inserts  by  a  single  tendon  into  the  olecranon  process  of 
the  ulna.  Its  three  heads  are  the  long,  external,  and  internal.  The  long  head  arises 
from  the  lower  edge  of  the  glenoid  cavity  and  the  scapular  border  below  it  for  2.5 
cm.  (i  in.).  It  blends  with  the  capsule  of  the  joint  and  tends  to  strengthen  it  at 
this  point.  When  the  arm  is  abducted,  this  tendon  is  closely  applied  to  the  capsule 
and  head  of  the  humerus,  and  when  the  head  escapes  in  luxation,  it  slips  out  anterior 
to  the  tendon.  The  external  head  arises  from  the  humerus  above  the  musculospiral 
groove  and  from  the  external  intermuscular  septum;  the  internal  head  arises  from 
the  humerus  below  the  musculospiral  groove  and  from  the  internal  and  the  lower 
part  of  the  external  intermuscular  septum  (Fig.  283). 

At  its  lower  end  the  triceps  inserts  into  the  olecranon  process,  the  upper  third 
of  the  ulna,  and  the  deep  fascia  of  the  back  of  the  forearm.  The  expansion  of  fascia 
from  the  olecranon  on  the  inner  side  is  thin  and  insignificant,  but  that  on  the  outer 
side,  on  the  contrary,  is  thick  and  strong,  and  when  fracture  of  the  bone  occurs  is  an 
important  factor  in  preventing  separation  of  the  fragments. 


THE  ARM. 


271 


Outer  head 
of  triceps 


THE  INTERMUSCULAR  SEPTA. 

The  deep  fascia  of  the  arm  completely  encircles  it,  like  a  tube.  It  is  continuous 
above  with  the  fascia  co\'ering  the  deltoid,  pectoralis  major  and  teres  major  muscles, 
and  axillary  fascia.  Below,  it  is  continuous  with  the  fascia  of  the  forearm  and  is 
attached  to  the  olecranon  and  internal  and  external  condyles. 

On  each  side  of  the  lower  half  of  the  humerus,  extending  from  the  condyles  and 
the  bone  above  outward  to  the  deep  fascia,  are  two  fibrous  partitions.  They  are 
the  internal  and  external  internniscular 
septa.  The  space  in  front  of  them  is  filled 
by  the  flexors,  the  biceps,  and  brachialis 
anticus,  and  the  space  behind  contains 
the  triceps  extensor.  The  external  sep- 
tum begins  at  the  external  condyle  and 
extends  above  to  the  tendon  of  the  del- 
toid, with  which  it  blends.  The  internal 
septum  begins  below  at  the  internal  con- 
dyle and  extends  above  to  the  coraco- 
brachialis.  The  radial  (musculospiral) 
nerve  and  anterior  terminal  branch  of 
the  (superior)  profunda  artery,  as  they 
wind  around  the  humerus  below  the  in- 
sertion of  the  deltoid,  pierce  the  external 
septum.  The  internal  septum  is  pierced 
high  up  by  the  ulnar  nerve  and  superior 
ulnar  collateral  (inferior  profunda)  artery 
as  they  emerge  at  about  the  level  of  the 
lower  portion  of  the  insertion  of  the 
coracobrachialis  to  pass  down  behind 
the  internal  condyle. 

These  intermuscular  septa  are  of 
importance  in  operative  procedures  be- 
cause they  indicate  the  limits  of  the  mus- 
cles and  position  of  nerves  and  vessels. 

SURFACE  ANATOMY. 

Inasmuch  as  the  movements  of  the 
elbow-joint  are  anteroposterior  only  and 
not  lateral,  the  muscles  are  principally 

on  the  front  and  back  and  not  on  the  "X  WSi^km  Anconeus 

sides.  Hence  on  looking  at  an  arm 
a  rounded  mass  is  seen  anteriorly  and 
posteriorly,  and  separating  them  on  the 
sides  can  be  seen  in  a  spare,  muscular 
individual,  distinct  furrows  called  the 
internal  and  external  bicipital  furrows. 
If  these  furrows  are  obscured  by  fat, 
one  can  still  feel  that  the  bone  is  nearer 
the  surface  at  these  points  than  else- 
where. The  anterior  muscle  mass  is 
formed   by   the   biceps    and    brachialis 

anticus  muscles,  the  posterior  mass  by  the  triceps.  The  bone  is  most  readily 
felt  at  the  insertion  of  the  deltoid  at  the  middle  of  the  outer  side  of  the  arm. 
From  this  point  directly  down  to  the  external  condyle  passes  the  external  inter- 
muscular septum  and  external  bicipital  furrow.  Winding  around  from  the  poste- 
rior edge  of  the  insertion  of  the  deltoid  is  the  radial  {iniisculospirai)  7ierve  and 
{supej'ior)  profunda  artery.  They  pierce  the  external  intermuscular  septum  and 
pass  downward  in  the  groove  formed  by  the  brachioradialis  (supinator  longus)  and 
extensor  muscles  on  the  outside  and  the  brachialis  anticus  on  the  inside.  On  the 
inner  side  of  the  arm  the  bicipital  furrow,  between  the  biceps  in  front  and  the  triceps 


Inner  head 
of  triceps' 


Fig.  283. — Triceps  and  anconeus  muscles. 


272 


APPLIED    ANATOMY. 


behind,  is  quite  evident  and  marks  the  internal  intermuscular  septum,  which  extends 
to  the  medial  (internal)  condyle.  In  front  of  it  lie  the  brachial  artery  and  veins, 
and  median  and  ?nedial  antebrachial  {internal)  cutaneous  nerve.  At  the  upper 
portion  of  the  inside  of  the  arm  can  be  seen  the  swell  formed  by  the  coracobrachialis 
muscle.  The  inner  or  posterior  border  of  the  coracobrachialis  is  continuous  with 
the  inner  border  of  the  biceps,  and  the  brachial  artery  follows  them.  The  coraco- 
brachialis muscle  ends  just  below  the  level  of  the  insertion  of  the  deltoid,  and,  of 
course,  can  neither  be  seen  nor  felt  below  that  point.  It  is  here  that  the  ulnar  nerve 
leaves  the  artery  to  pierce  the  internal  intermuscular  septum  in  company  with  the 
superior  2ilnar  collateral  {inferior profunda)  artery  to  reach  the  groove  behind  the 
internal  condyle.  The  brachial  artery  is  covered  only  by  the  skin  and  superficial  and 
deep  fascia,  and  can  be  felt  pulsating  along  the  inner  edge  of  the  biceps  muscle  and 
tendon;  it  can  be  compressed  against  the  bone  by  pressure  directed  outwardly 
above  and  inclining  more  posteriorly  as  the  artery  progresses  down  toward  the  bend 
of  the  elbow.  It  is  on  the  inner  side  of  the  arm  in  the  upper  two-thirds,  and  is  more 
anterior  in  the  lower  one- third  (Fig.  284). 

The  cephalic  vein  runs  up  the  external  bicipital  furrow  and  the  basilic  up  the 
internal.  At  the  junction  of  the  middle  and  lower  thirds  of  the  arm  the  basilic 
pierces  the  deep  fascia  and  from  that  point  runs  up  beneath  it  and  joins  with  the 
internal  vena  conies  opposite  the  lower  border  of  the  teres  major  or  subscapularis. 

THE  BRACHIAL  ARTERY. 

The  arm  being  abducted,  the  course  of  the  brachial  artery  is  indicated  by  a 
line  drawn  from  the  inner  edge  of  the  coracobrachialis  muscle,  at  the  junction  of 
the  anterior  and  middle  thirds  of  the  axilla,  above,  to  a  point  just  inside  the  tendon 
of  the  biceps  at  the  bend  of  the  elbow,  below,  midway  between  the  two  condyles 
of  the  humerus.  This  lies  in  the  internal  bicipital  furrow  along  the  inner  edge  of 
the  biceps  muscle.  The  artery  is  superficial  in  its  entire  course.  It  is  accom- 
panied by  two  small  venae  comites,  which  closely  embrace  it.  The  basilic  vein 
runs  along  its  inner  side.  The  median  nerve  lies  on  the  artery  to  its  outer  side 
above,  then  directly  on  it  and  a  little  to  its  inner  side  at  the  middle,  and  passes 
to  its  inner  side  at  the  bend  of  the  elbow.  The  medial  antebrachial  (internal) 
cutaneous  nerve,  much  smaller  than  the  median,  passes  down  along  the  inner  side 
of  the  artery  between  it  and  the  basilic  vein  to  pierce  the  fascia  about  the  middle  of 
the  arm  (Fig.  285). 

The  ulnar  7ierve  lies  to  the  inner  side  of  the  artery  above  and  is  posterior  to  the 
basilic  vein.  About  opposite  the  insertion  of  the  coracobrachialis  it  diverges  from 
the  artery  to  pierce  the  internal  intermuscular  septum. 


Older  Side 
Median  nerve,  above 
Coracobrachialis 
Biceps 
Vena  comes 


Relations  of  the  Brachial  Artery 

In  Front. 
Skin  and  fascia 

Overlapped  by  coracobrachialis  and  biceps 
Median  basilic  vein 
Bicipital  fascia 
Median  nerve 

Intter  Side 
Medial  antebrachial  (int.) 
Brachial  cutaneous  and 

Artery  ulnar  nerves 

Median  nerve  below 
Basilic  vein 
Vena  comes 
Behind 
Triceps  (long  and  inner  heads) 
Radial  (musculospiral)  nerve 
(Sup.)  profunda  artery 
Coracobrachialis  muscle 
Brachialis  anticus  muscle 


THE  ARM. 


273 


Branches  of  the  Brachial  Artery, — The  branches  of  the  brachial  artery  are 
the  profunda  (superior),  the  superior  ulnar  collateral  (inferior  profunda),  the  nutrient, 
muscular,  and  inferior  ulnar  collateral  (anastomotica  magna). 


Deltoid 


Supinators  and  extensors 


Pronators  and  flexors 

Internal  bicipital  furrow 

Triceps,  long  and  inner  heads 

Brachial  artery 

Coracobrachialis  muscle 
Fig.  284. — Surface  anatomy  of  the  arm. 

Not  infrequently  the  brachial  artery  instead  of  dividing  into  the  radial  and  ulnar 
opposite  the  neck  of  the  radius  divides  higher  up.  This  is  called  a  high  division  and 
is  seen  most  often  in  the  upper  third  of  the  arm.      The  two  vessels  may  follow  the 


Musculocutaneous  nerve 

Brachial  artery 
Coracobrachialis     -' 
Median  nerve 

Biceps 


Latissimus  dorsi 


Brachialis  anticus 


Superior  profunda  artery 
Musculospiral  nerve 
Inner  head  of  triceps 
Ulnar  nerve 

Inferior  profunda  artery 


Anastomotica  magna  arterj' 

Basilic   vein 

Fig.  285. — Dissection  of  the  arm,  viewed  from  the  inner  side. 


usual  course  in  the  arm,  or  the  radial  may  run  under  the  biceps  tendon,  instead  of 
over  it,  and  the  ulnar  may  accompany  the  median  nerve  in  front  of  the  medial  con- 
dyle or  the  ulnar  nerve  behind  it. 


274 


APPLIED    ANATOMY. 


The  prof  mida  is  given  off  just  below  the  lower  edge  of  the  posterior  fold  of  the 
axilla  (teres  major).  It  accompanies  the  radial  (musculospiral)  nerve  around  the 
arm  to  its  outer  side;    it  sends  one  branch,  the  radial  collateral,  to  the  front  of  the 


Median  nerve 
Biceps  muscle     / 


Ulnar  nerve 


Brachial  artery 


.  Superior  profunda  (A.  profunda 
brachii) 

•  Brachial  artery 

.  Inferior  profunda  (coUateralis 
ulnaris  superior) 


Anastomotica  magna  (collate- 
"ralis  ulnaris  inferior) 


Fig.  286. — Ligation  of  the  brachial  artery  in  the  middle  of  the  arm  showing  the  median  nerve  lying  on  the  artery 

and  the  ulnar  nerve  to  its  inner  side. 

elbow  and  the  middle  collateral  behind  it.     The  superior  ulnar  coIlate7-al  artery 
(inferior  profunda)  comes  off  about  opposite  the  insertion  of  the  coracobrachialis 

muscle.  It  is  much  smaller  than  the  pro- 
funda and  with  the  ulnar  nerve  pierces  the 
internal  intermuscular  septum.  The  nutri- 
ent artery  comes  off  close  to  the  origin  of 
the  superior  ulnar  collateral  (inferior  pro- 
funda) or  is  a  branch  of  it.  It  passes  down- 
ward in  the  bone  in  a  direction  toward  the 
elbow-joint.  The  inferior  ulnar  collateral 
(anastomotica  magna)  is  given  off  5  cm. 
(2  in.)  above  the  elbow  and  passes  inward 
over  the  brachialis  anticus  to  divide  into 
two  branches,  one  going  down  in  front  and 
the  other  behind  the  elbow. 

Ligation  of  the  Brachial  Artery. 
— In  ligating  the  brachial  artery.  Heath 
strongly  advises  that  the  arm  be  held  by  an 
assistant  in  an  abducted  position  with  the 
hand  supine,and  not  allowed  to  rest  on  any- 
thing. The  object  of  this  is  to  avoid  hav- 
ing the  artery  overlapped  by  the  triceps  be- 
ing pushed  up  and  thus  becoming  obscured. 
The  incision  is  to  be  made  in  the  line 
from  the  inner  edge  of  the  coracobrachialis 
to  a  point  midway  between  the  tips  of  the 
condyles.  The  deep  fascia  is  to  be  opened 
and  the  inner  edge  of  the  biceps  muscle 
is  to  be  sought  for,  recognized,  and  held 
outward.  The  pulsation  of  the  artery  may 
indicate  its  position  in  the  living;  if  not,  it 
is  to  be  sought  for  to  the  inner  side  of  the 
edge  of  the  biceps.  The  median  nerve  is 
not  to  be  mistaken  for  it.  It  will  lie  either 
over  its  middle  or  to  its  inner  side  if  low  down  and  to  its  outer  side  if  high  up  (Fig.  286). 
The  ulnar  nerve  lies  on  the  inner  side  of  the  artery  as  far  as  the  middle  of  the 


-Radial  recurrent 
-Ulnar  recurrent 


-Interosseous  recurrent 
-  Posterior  interosseous 


— Anterior  interosseous 
"Radial  artery 
-Ulnar  artery 


'A 


Fig.  287. — Collateral  circulation  after  ligation  of  the 
brachial  artery  at  the  bend  of  the  elbow. 


THE  ARM.  275 

arm,  it  then  leaves  the  artery.  Below  the  middle,  if  the  search  is  made  too  far 
posteriorly,  the  ulnar  nerve  and  basilic  vein  will  be  encountered.  The  ulnar  nerve 
should  not  be  seen,  the  basilic  vein  and  median  nerve — and  above  the  middle  of  the 
arm  the  medial  antebrachial  (internal)  cutaneous  nerve — are  to  be  displaced  to  the 
inner  side. 

The  needle  is  to  be  passed  from  within  outward.  Care  must  be  taken  not  to 
mistake  a  large  superior  or  inferior  profunda  for  the  main  trunk.  A  high  division 
of  the  brachial  may  give  two  vessels  of  approximately  equal  size.  Of  course,  in  such 
a  case  both  must  be  ligated. 

Collateral  Circulation. — If  the  ligature  is  placed  above  the  profunda  (superior) 
branch,  the  anterior  and  posterior  circumflex  will  anastomose  with  the  profunda 
(superior)  and  superior  ulnar  collateral  (inferior  profunda)  below.  If  the  ligature  is 
placed  between  the  profunda  and  superior  ulnar  collateral  arteries,  the  profunda 
(superior)  will  anastomose  below  with  the  radial  recurrent  and  posterior  interosseous 
recurrent  on  the  outer  side  and  will  also  communicate  with  the  inferior  ulnar 
collateral  (anastomotica  magna)  and  superior  ulnar  collateral  (inferior  profunda) 
on  the  inside  (Fig.  287).  If  below  the  superior  ulnar  collateral  (inferior  profunda) 
then  the  profunda  (superior)  would  anastomose  with  the  radial  and  posterior  inter- 
osseous recurrents  on  the  outside,  and  the  superior  ulnar  collateral  (inferior  profunda) 
with  the  inferior  ulnar  collateral  (anastomotica  magna)  and  the  anterior  and  posterior 
ulnar  recurrents. 

AMPUTATION   OF   THE   ARM. 

In  amputation  one  has  to  deal  with  a  part  of  the  body  that  is  approximately 
cylindrical  in  shape  and  that  contains  only  a  single  bone  entirely  surrounded  by 
soft  parts.  The  circular  method  is  more  applicable  to  amputation  of  the  arm  below 
the  insertion  of  the  deltoid  than  to  any  other  part  of  the  body,  but  nevertheless  in 
some  cases,  particularly  in  muscular  arms,  difficulty  may  be  experienced  in  turning 
back  the  cuff.  In  such  cases  the  cuf5  is  slit  by  the  surgeon  and  the  operation 
becomes  one  of  square  skin  flaps.  For  this  reason  flap  amputations  are  usually  to 
be  preferred. 

The  arm  may  be  amputated  at  any  place,  high  up  or  low  down.  Artificial 
appliances  for  the  upper  extremity  are  comparatively  useless;  hence  the  height  of 
division  of  the  bone  is  determined  by  the  injury. 

As  it  is  desirable  to  retain  the  head  of  the  bone  and  tuberosities,  if  pos- 
sible, in  order  to  preserve  the  shape  of  the  shoulder  and  retain  the  attachment 
of  the  muscles,  amputation  may  be  done  through  the  surgical  neck.  This  is  just 
below  the  epiphyseal  line.  In  performing  a  flap  amputation  the  soft  parts  should 
cover  or  cap  the  bone  like  a  hemisphere:  therefore  the  total  length  of  the  flaps  should 
be  equal  to  one-half  the  circumference  of  a  sphere  whose  diameter  is  the  diameter  of 
the  limb  at  the  point  of  section  of  the  bone.  If  the  diameter  of  the  limb  is  4  inches, 
then  the  total  length  of  the  flaps  should  be  approximately  6  inches.  If  the  flaps 
were  of  equal  length  then  each  would  be  3  inches  long.  If  there  was  only  one  flap, 
it  would  be  6  inches  long. 

It  is  an  axiom  in  surgery  that  in  flap  amputations  the  artery  should  be  contained 
in  the  shorter  flap.  The  operator  should  accurately  know  the  course  of  the  artery 
and  avoid  making  his  flaps  in  such  a  manner  as  to  bring  the  vessel  in  the  angle  of  the 
wound.  Otherwise  the  artery  is  liable  to  be  split.  In  a  high  amputation  the 
external  flap  may  be  long  and  the  internal  short.  In  the  middle  of  the  arm  antero- 
posterior flaps  are  preferred  and  the  artery  is  included  in  the  posterior  flap.  If  the 
amputation  is  in  the  lower  third  and  the  flaps  are  anteroposterior,  then  the  artery  of 
necessity  is  in  the  anterior  flap. 

Above  the  middle  of  the  arm  the  deltoid,  coracobrachialis,  and  biceps  muscles 
are  free  and  therefore  retract  markedly  when  cut.  In  the  middle  the  biceps  only  is 
free  and  the  same  is  the  case  in  the  lower  third.  The  triceps  and  brachialis  anticus 
are  attached  to  the  bone  and  therefore  retract  but  little  when  cut.  Surgeons  have 
called  attention  to  the  necessity  of  being  careful  to  see  that  the  radial  (musculospiral) 
nerve  is  properly  divided,  otherwise  it  may  be  torn  by  the  saw.     The  groove  in  which 


276 


APPLIED   ANATOMY. 


it  lies  may  be  unusually  deep  and  necessitate  a  special  effort  to  divide  it.  On  the  face 
of  the  stump  the  artery  is  to  be  looked  for  to  the  inner  side  of  the  bone  in  the  upper 
two-thirds  of  the  arm  and  anteriorly  in  the  lower  third.  Lying  on  it  will  be  the 
median  nerve  and  to  its  inner  side  the  ulnar  nerve.  At  the  level  of  the  insertion  of 
the  deltoid  the  radial  (musculospiral)  nerve,  accompanied  by  the  (superior)  profunda 
artery,  will  be  posterior  or  toward  the  outer  side.  The  superior  ulnar  collateral  (in- 
ferior profunda)  artery  is  given  off  at  the  level  of  the  insertion  of  the  coracobrachialis 
muscle,  which  is  about  opposite  the  insertion  of  the  deltoid.  It  accompanies  the  ulnar 
nerve.  A  nerve  may  be  seen  lying  between  the  biceps  and  brachialis  anticus.  It  is  the 
musculocutaneous  which  becomes  superficial  just  above  the  bend  of  the  elbow  (Fig.  288) . 


Median  nerve 

Brachial  artery 
Internal  cutaneous  nerve  ^ 


Ulnar  nerve  and  inferior 
profunda  artery 


Coraco-brachialis 

Musculospiral  nerve  and 
superior  profunda  artery 


Biceps 
Musculocutaneous  nerve 


Brachialis  anticus 


Deltoid 


Triceps 


Triceps 


Fig.  288. — Amputation  just  above  the  middle  of  the  arm. 

Five  cm.  (2in. )  above  the  elbow  the  inferior  ulnar  collateral  (anastomotica 
magna)  artery  may  be  expected  to  be  encountered  passing  down  and  in  over  the 
brachialis  anticus  muscle. 


FRACTURES   OF   THE   HUMERUS. 


Fractures  of  the  Shaft  of  the  Humerus. — There  seems  to  be  but  little  doubt 
that  in  many  cases  the  character  of  displacement  of  the  fragments  in  fracture  of  the 
shaft  of  the  humerus  is  due  to  the  mode  of  injury  and  not  to  muscular  action.  This 
being  so  accounts  for  there  being  less  uniformity  in  these  fractures  than  in  those 
higher  up,  which  have  already  been  considered.  There  are  some  cases,  however,  in 
which  muscular  action  does  play  a  part  and  the  possible  influence  of  the  muscles 
should  be  understood. 

The  line  of  fracture  is  usually  more  or  less  oblique,  in  rare  cases  nearly  trans- 
verse, but  the  displacement  is  often  not  marked.  Notwithstanding  this  latter  fact, 
non-union  of  fracture  of  the  shaft  of  the  humerus  is  one  of  the  most  frequent  of  any 
in  the  body. 

Muscular  action  shows  its  influence  most  markedly  in  producing  displacements 
in  three  directions,  viz. ,  in  towards  the  body,  out  away  from  the  body,  and  directly 
anteriorly. 


THE  ARM. 


277 


There  are  two  main  points  where  fracture  occurs;  immediately  above  the  inser- 
tion of  the  deltoid  and  below  it. 

Frachire  above  the  Insertion  of  the  Deltoid. — The  bone  may  be  fractured  imme- 
diately above  the  deltoid  insertion.  In  this  case  the  powerful  axillary  fold  muscles, 
pectoralis  major,  teres  major,  and  latissimus  dorsi,  being  attached  to  the  upper  frag- 
ment, tend  to  draw  it  toward  the  body,  while  the  deltoid  tends  to  draw  the  lower 
fragment  out.  The  influence  of  the  other  muscles,  biceps,  coracobrachialis,  and  triceps, 
would  be  to  increase  the  overlapping  (Fig.  289). 

Fracture  belozv  the  Deltoid  Insertion. — This  is  the  more  common  site  of  fracture. 
The  line  of  fracture  is  most  apt  to  be  from  above  downward  and  outward.  The 
upper  fragment  is  displaced  anteriorly  by  the  coracobrachialis  and  anterior  portion 


Pectoralis  major 


Latissimus  dorsi 


Deltoid 


Teres  major 


Fig.  289. — Fracture  of  the  shaft  of  the  humerus  just  above  the  insertion  of  the  deltoid  and  below  the  inser- 
tion of  the  axillary  fold  mviscles.  The  lower  fragment  is  seen  to  be  drawn  outward  by  the  deltoid;  the  upper  frag- 
ment is  seen  to  be  drawn  inward  by  the  pectoralis  major,  latissimus  dorsi,  and  teres  major. 


of  the  deltoid  and  is  drawn  outward  by  the  deltoid  aided  by  the  supraspinatus.  To 
relax  the  deltoid  the  arm  is  sometimes  dressed  in  an  abducted  position  (Fig.  290). 

Non-Union. — The  humerus  has  muscles  attached  to  it  almost  throughout  its 
entire  length,  and  w^hen  the  sharp  ends  of  the  fragments  are  displaced  they  probably 
become  fixed  in  the  surrounding  muscle,  and  proper  apposition  of  the  fragments  is 
prevented,  hence  non-union.  Hamilton  believed  that  lack  of  proper  fixation  was  also 
a  prominent  cause. 

The  Radial  (Musculospiral)  Nerve. — In  fracture  of  the  shaft  of  the 
humerus,  paralysis  of  the  extensors  due  to  injury  of  the  radial  nerve  is  compara- 
tively common.  It  also  occurs  from  pressure  due  to  the  use  of  crutches,  to  sleep- 
ing  on  the  arm,  etc.     The  other  nerves  are  too   far  removed  from  the  bone   to 


278 


APPLIED    ANATOMY. 


be  injured,  but  the  radial  (musculospiral)  lies  on  the  bone  in  the  radial  (musculo- 
spiral)  groove  in  approximately  the  middle  third  of  the  bone.  It  comes  into  contact 
with  the  bone  posteriorly  above  the  insertion  of  the  deltoid  and  leaves  the  bone  on 
its  outer  anterior  surface  to  pass  between  the  brachialis  anticus  and  brachioradialis 
(supinator  longus) muscles.  Paralysis  may  be  caused  (i)  by  direct  injury  to  the 
nerve  at  the  time  the  fracture  is  received.  (2)  By  subsequent  changes  in  the  nerve 
due  to  its  being  stretched  over  the  sharp  edge  of  a  fragment.  (3)  By  being  included  in 
callus.  The  last  is  probably  much  more  rarely  the  case  than  the  two  former  (Fig.  291). 
Paralysis  should  be  examined  for  early  in  the  course  of  treatment.  Too  often  it 
is  detected  only  after  the  splints  have  been  removed,  and  then  it  is  apt  to  be  ascribed 
to  improper  treatment  or  to  misapplied  pressure.     The  symptoms  of  involvement  of 


Deltoid 


Infraspinatus 


Teres  minor 


Site  of  fracture 


Teres  major 


Latissimus  dorsi 


Long  head  of  triceps 


External  head  of  triceps 


Fig.  290. — Posterior  view  of  a  fracture  of  the   shaft  of  the   humerus   just   below  the  insertion  of  the   deltoid, 
showing  the  influence  of  that  muscle  in  producing  abduction  of  the  upper  fragment. 

the  musculospiral  nerve  are  wrist-drop  and  diminution  of  the  power  of  supination, 
also  some  sensory  changes  in  the  dorsum  of  the  hand  and  forearm. 

This  nerve  is  frequently  paralyzed  from  pressure  in  cases  in  which  there  is  no 
fracture,  as  from  sleeping  on  the  arm,  the  use  of  crutches,  and  also  in  certain  sys- 
temic affections,  such  as  lead  poisoning.  It  suppHes  the  triceps,  part  of  the  brachialis 
anticus,  brachioradialis  (supinator-  longus),  and  extensor  carpi  radialis  longior 
muscles  in  the  arm,  and  then  proceeds  to  the  forearm.  The  branch  to  the  triceps  is 
given  off  before  the  nerve  enters  the  musculospiral  groove,  hence  is  not  often  injured, 
and  loss  of  extension  of  the  forearm  is  not  often  present;  even  paralysis  of  the  other 
muscles  mentioned  is  not  common,  the  forearm  muscles  being  mostly  affected.  The 
branch  to  the  inner  head  of  the  triceps  also  supplies  the  anconeus. 


THE   ARM. 


279 


OPERATIONS   ON   THE   ARM. 

Caries  or  necrosis  of  the  humerus  may  necessitate  operative  interference  at  almost 
any  part  of  the  arm.  The  same  may  be  said  of  wounds.  In  operative  procedures 
it  is  sometimes  desirable  to  avoid  important  structures  and  at  others  to  find  them. 


Deltoid 


Brachialis  anticus 


Long  head  of  triceps 


Outer  head  of  triceps 
Radial  (musculospiral)  nerve 

Superior  profunda  artery 

Brachioradialis 

Extensor  carpi  radialis  longior 

Extensor  muscles  of  forearm 
External  condyle 


Fig.  291. — The  radial  (muscolospiral)  nerve  and  outer  side  of  arm. 

The  important  structures  run  lengthwise,  hence  transxerse  incisions  are  not  to  be 
used.  Most  of  the  large  vessels  and  nerves  pass  down  the  inner  side  of  the  arm, 
hence  this  region  is  usually  avoided.  The  bone  can  readily  be  reached  by  an  incision 
downward  from  the  insertion  of  the  deltoid,  but  no  operation  is  to  be  done  in  this 
region  without  a  thorough  familiarity  with  the  course  of  the  musculospiral  nerve. 


28o  APPLIED    ANATOMY. 

A  line  drawn  on  the  posterior  surface  of  the  arm  from  behind  and  above  the  insertion 
of  the  deltoid  to  the  groove  on  the  anterior  surface  between  the  brachialis  anticus  and 
brachioradialis  (supinator  longus)  just  above  and  to  the  inner  side  of  the  external 
condyle  will  indicate  its  course.  If  exposed  during  an  operation  bleeding  from  the 
accompanying  (superior)  profunda  artery  may  be  expected.  The  median  and  ulnar 
nerves  give  off  no  branches  in  the  upper  arm.  The  median  can  be  readily  located 
by  its  relation  to  the  artery.  It  lies  to  the  outer  and  anterior  side  of  the  brachial 
artery  above,  then  in  front,  and  then  to  its  inner  side  below.  The  ulnar  nerve  lies 
to  the  inner  side  of  the  artery  and  between  it  and  the  vein  posteriorly.  In  the  middle 
of  the  arm,  it  leaves  it  to  pierce  and  pass  beneath  the  internal  intermuscular  septum 
and  thence  behind  the  medial  (internal)  condyle.  Operations  involving  it  would 
be  accompanied  by  bleeding  from  its  companion  the  superior  ulnar  collateral  artery 
(inferior  profunda). 

In  operations  on  the  lower  portion  of  the  bone  the  position  of  the  inferior  ulnar 
collateral  (anastomotica  magna),  5  cm.  (2  in.)  above  the  elbow,  should  be  borne  in 
mind.  It  runs  on  the  brachialis  anticus  muscle  and  towards  the  inner  and  not  the 
outer  side.  Incisions  on  the  outer  side  will  encounter  the  cephalic  vein  in  the  external 
bicipital  furrow.  Incisions  on  the  inner  side  will  encounter  the  basilic  vein  ;  at  the 
junction  of  the  lower  and  middle  thirds  of  the  arm  it  pierces  the  deep  fascia. 

REGION    OF  THE   ELBOW. 

The  elbow  is  so  named  because  at  this  point  the  arm  is  usually  bent.  A  joint  is 
here  inserted  which  permits  of  flexion  and  extension  ;  when  the  arm  is  fully  extended 
the  "elbow"  might  be  said  to  have  disappeared.  The  lower  end  of  the  humerus 
forms  the  proximal  portion  of  the  joint  and  the  upper  ends  of  the  ulna  and  radius  form 
its  distal  portion.  Ligaments  join  these  bones  together  to  form  the  joint,  and  the 
blood-vessels  and  nerves  change  in  .character  in  this  region  as  they  pass  from  the  arm 
to  the  forearm.  '     l'  * 

The  bones  are  frequently  subject  to  fractures  which  are  of  an  exceedingly  puz- 
zling and  disabling  character.  The  joint  becomes  luxated  and  the  vessels  and  nerves 
are  not  infrequently  injured.  A  thorough  knowledge  of  the  anatomy  of  the  region 
is  absolutely  essential  to  the  proper  treatment  of  these  affections. 

BONES   OF   THE   ELBOW. 

Humerus. — The  lower  end  of  the  humerus  broadens  laterally  and  is  slightly 
concave  on  its  anterior  surface  ;  this  causes  the  articular  surfaces  to  look  downward 
and  forward  and  not  backward.  It  carries  two  articular  surfaces:  one,  the  trochlea,  for 
the  ulna,  and  the  other,  the  capitellum,  for  the  radius.  The  trochlea,  descending 
lower  than  thecapitellum,  causes  the  line  of  the  joint  to  incline  downward  and  inward 
instead  of  being  directly  transverse,  thus  producing  the  "  carrying  angle"  (Fig.  294). 
Extending  from  the  edges  of  the  articular  surfaces  outward,  one  on  each  side,  are  the 
condyles,  medial  {internal^  and  lateral  {extertial) . 

Chaussier  gave  the  name  epico?tdyle  to  the  condyles.  He  called  the  medial 
condyle  the  epitrochlea  and  the  lateral  (external)  condyle  the  epicondyle.  Henle 
called  the  internal  condyle  the  epicondylus  medialis  and  the  external  condyle  the 
epicondylus  lateralis.  The  name  epicondyle  is  now  quite  generally  employed  by  both 
surgical  and  anatomical  writers  to  designate  the  projecting  extra-articular  portion  of 
the  condyles,  so  that  the  terms  are  practically  synonymous  (Fig.  293). 

From  the  condyles  two  ridges  run  upward.  The  lateral  {exteryial)  supracon- 
dylar ridge  is  the  more  marked  of  the  two  and  gives  origin  to  the  brachioradialis 
(supinator  longus)  and  the  extensor  carpi  radialis  longior  muscles,  and  passes 
posterior  to  the  deltoid  eminence  to  be  continuous  with  the  posterior  lip  of  the 
radial  (musculospiral)  groove.  The  medial  {internal^  supracondylar  ridge  is  much 
less  prominent  than  the  lateral  and  soon  blends  with  the  shaft  of  the  bone.  Above 
the  trochlea  and  capitellum  anteriorly  are  two  fossae,  the  coronoid  and  the  radial, 
to  receive  the  coronoid  process  and  head  of  the  radius  when  the  arm  is  in  complete 


REGION    OF   THE    ELBOW. 


281 


flexion.  On  the  posterior  surface  there  is  another  depression,  the  olecranon  fossa,  to 
receive  the  olecranon  process  in  extreme  extension.  The  projecting-  hook-Uke  shape 
of  the  median  condyle  causes  it  to  be  more  frequently  fractured  than  the  less  promi- 
nent lateral  condyle.  The  two  condyles  are  readily  felt  directly  beneath  the  skin  and 
are  the  only  points  of  the  humerus  that  are  really  subcutaneous. 

Ulna. — The  upper  extremity  of  the  ulna  articulates  above  with  the  trochlea  of 
the  humerus  and  on  its  outer  side  with  the  radius.  Its  upper  end  is  the  olecranon 
process.  The  posterior  portion  of  this  process  is  called  the  tip  of  the  olecranon  and 
is  continuous  with  the  posterior  surface  of  the  ulna,  which  is  subcutaneous.      Immedi- 


FiG.  292. — .\nterior  view  of  bones  of  right  elbow. 


Fig.  293. — Posterior  view  of  bones  of  elbow. 


ately  in  front  of  the  olecranon  is  a  large  hollow,  which  receives  the  trochlea.  It  is 
called  the  greater  sigmoid  cavity.  The  anterior  margin  of  the  cavity  is  called  the 
coro7ioid process.  On  the  outer  side  of  the  coronoid  process  is  a  hollow  called  the 
lesser  sigmoid  cavity,  which  receives  the  head  of  the  radius.  Fracture  of  the  bone 
frequently  occurs  through  the  narrow  portion  of  the  olecranon  process  into  the  greater 
sigmoid  cavity. 

Radius. — The  radius  ends  above  in  a  fiat  rounded  head.  The  upper  surface 
of  this  head  articulates  with  the  capitellum.  The  lateral  surface  articulates  internally 
with  the  lesser  sigmoid  cavity  of  the  ulna.  The  remainder  of  the  circumference  of 
the  head  is  embraced  by  the  orbicular  ligament.  Immediately  below  the  head  is  the 
constricted  neck  and  bicipital  tuberosity.  To  the  posterior  half  of  this  latter  the 
tendon  of  the  biceps  is  attached,  but  its  anterior  portion  is  smooth  and  provided  with 
a  bursa.  The  head  of  the  radius  is  subcutaneous  posteriorly,  but  the  rest  is  too  much 
covered  by  muscles  to  be  readily  palpated. 


2S2 


APPLIED    ANATOMY. 


ELBOW-JOINT. 

By  the  term  elbow-joint  is  meant  the  articulation  between  the  humerus  above 
and  the  ulna  and  upper  surface  of  the  radius  below.  The  articulation  between  the 
upper  end  of  the  radius  and  the  ulna  forms  the  superior  radio-ulnar  articulation  and 
does  not  belong  to  the  elbow-joint  proper.  As  has  already  been  pointed  out,  the 
ulna  articulates  with  the  trochlea  and  the  radius  with  the  capitellum. 

The  elbow-joint  is  a  pure  hinge-joint.  The  articulation  between  the  trochlea 
and  ulna  is  so  .shaped  as  to  allow  no  lateral  motion,  but  only  an  anteroposterior  one. 
The  articulation  between  the  capitellum  and  upper  surface  of  the  head  of  the  radius 

is,  on  the  contrary,  a  ball-and-socket  joint.  The 
socket,  it  is  true,  is  shallow,  but  it  is  perfectly 
spherical,  made  so  by  the  rotary  movement  of  the 
radius  in  pronation  and  supination.  Hence  it  fol- 
lows that  the  shape  and  continuity  of  the  upper  ex- 
tremity depends  upon  the  articulation  of  the  ulna 
with  the  humerus:  it  further  follows  that  if  the 
radius  be  removed  from  the  elbow-joint  the  forearm 
would  still  be  held  in  its  proper  relation  to  the  arm, 
but  if  the  ulna  be  removed  the  stability  of  the  joint 
would  be  lost  and  the  forearm  would  move  in  any 
direction,  laterally  as  well  as  anteroposteriorly.  It 
is  for  this  reason  that  injuries  involving  the  medial 
condyle  and  trochlea  are  more  liable  to  be  followed 
by  serious  disability  than  are  those  of  the  lateral 
condyle  and  capitellum. 

The  movement  of  the  joint  takes  place  around 
a  transverse  axis,  which  passes  from  side  to  side 
below  and  in  front  of  the  condyles.  The  forearm 
can  be  extended  to  an  angle  of  i8o  degrees,  or  a 
straight  line,  with  the  arm.  It  can  be  flexed  to  an 
angle  of  30  to  40  degrees.  Sometimes  it  cannot  be 
flexed  so  much,  so  that  if  after  an  injury  to  the 
joint  the  patient  can  flex  the  elbow  to  half  a  right 
angle,  or  45  degrees,  he  may  be  regarded  as  hav- 
ing regained  a  normal  amount  of  motion. 

Carrying  Angle. — The  axis  of  motion  of  the 
joint  is  not  exactly  transverse,  but  slopes  slightly 
from  the  outside  downward  and  inward.  The 
effect  of  this  is  to  give  a  slight  obliquity  to  the 
motions  of  flexion  and  extension.  This  obliquity 
is  not  noticeable  except  in  extreme  extension  and 
flexion.  When  the  forearm  is  completely  extended 
it  is  seen  to  lie  not  in  the  axis  of  the  arm  but  to 
bend  outward  from  the  elbow  at  an  angle  of  170 
degrees.  This  angle  is  called  the  ' '  carrying  angle, ' ' 
because  by  resting  the  elbow  against  the  side,  any  article  which  is  carried  in  the  ex- 
tended hand  is  kept  away  from  the  body.  Sometimes  the  line  of  the  forearm  is  almost 
straight  with  that  of  the  arm,  at  others  the  deflection  may  amount  to  15  degrees.  It 
may  vary  on  the  two  sides  and  10  degrees  may  be  considered  an  average;  Woolsey 
gives  6  degrees  as  the  average.  This  carrying  angle  becomes  lost  in  certain  cases  of 
fracture  of  the  elbow,  as  will  be  pointed  out  later.  As  the  elbow  is  flexed  the  carrying 
angle  disappears  (see  Fig.  294). 

When  flexion  is  complete  the  ulna  instead  of  coming  up  toward  the  head  of  the 
humerus  inclines  inward  at  an  angle  of  10  degrees.  Morris  states  that  the  hand  has 
a  tendency  to  point  to  the  middle  of  the  clavicle,  which  would  make  an  angle  of  20 
degrees.     This  we  believe  to  be  too  great. 


Fig.  294. — The  carrying  angle;  formed 
by  the  deviation  outward  of  the  axis  of  the 
forearm  from  the  axis  of  the  arm. 


REGION    OF   THE    ELBOW. 


283 


LIGAMENTS    OF   THE    ELBOW. 

The  ligaments  of  the  elbow-joint  are  four  in  number — anterior,  posterior,  internal 
lateral,  and  external  lateral. 

In  all  joints  there  are  two  kinds  of  ligaments.  One  kind  serves  to  retain  the 
synovial  fluid;  it  is  a  capsular  ligament  and  is  usually  thin;  the  other  kind  is  thick, 
firm,  and  strong,  and  is  intended  to  bind  the  bones  together  and  prevent  their  dis- 
placement and  to  limit  movemenl:.  These  two  kinds  of  ligaments  often  blend 
together  so  that  it  is  impossible  to  say  where  one  begins  and  the  other  ends;  at  other 
places  they  are  quite  distinct.  If  an  elbow-joint  is  distended  with  effusion  (or  wax) 
the  distinction  is  readily  seen.  The  capsule  becomes  distended  in  front  and  behind, 
while  at  the  sides  the  ligaments  remain  closely  applied  to  the  bones;  hence  we  learn 
that  the  anterior  and  posterior  ligaments  are  capsular  in  their  function  while  the 
lateral  ligaments  are  retentive.      These  will  be  considered  more  in  detail  later. 

Superior  Radio-nhiar  Articulation. — While  the  superior  radio-ulnar  articula- 
tion is  not  considered  a  part  of  the  elbow-joint  proper,  it  is  nevertheless  so  closely 


Fig.  295. — The  external  lateral  ligament  of  the  elbow- joint,  showing  its  A  shape.  Its  upper  end  is  attached 
to  the  external  condyle  of  the  humerus:  its  lower  ends  are  attached  to  the  ulna.  The  circular  fibres  surrounding 
the  head  of  the  radius  are  called  the  orbicular  ligament. 

associated  with  it  that  it  cannot  be  ignored.  The  head  of  the  radius,  in  addition  to 
its  movements  of  flexion  and  extension  on  the  humerus,  possesses  a  motion  of  rotation. 
In  order  that  it  may  rotate  properly  the  ligaments  are  arranged  in  a  peculiar  manner. 
Its  motion  in  respect  to  the  ulna  is  a  purely  rotary  one,  so  that  it  is  bound  to  the 
ulna  by  a  ligament  which  encircles  its  head,  called  the  orbicular  ligament.  The 
bulk  of  the  ligament  encircles  three-fourths  of  the  head  of  the  radius  and  is  attached 
at  its  ends  to  the  anterior  and  posterior  edges  of  the  lesser  sigmoid  cavity  of  the  ulna. 
Its  lower  fibres  are  continuous  below  the  lesser  sigmoid  cavity,  forming  a  complete 
circle.  The  upper  edge  of  this  orbicular  ligament  blends  with  the  anterior  ligament 
in  front,  the  posterior  behind,  and  the  external  lateral  at  the  side.  We  thus  see  that 
as  the  anterior  and  posterior  ligaments  are  capsular  in  their  function  the  radius  is 
kept  in  place  by  the  external  lateral  ligament,  which  branches  below  in  the  form  of 
the  letter  Y  to  blend  with  the  orbicular  ligament.  When  we  consider  that  these 
fibres  are  hardly  inserted  at  all  into  the  radius,  but  pass  over  it  to  the  ulna,  it  is 
evident  that  this  part  of  the  joint  is  comparatively  weak  and  not  an  excessive  amount 
of  force  would  be  required  to  pull  the  head  of  the  radius  from  beneath  the  orbicular 


284 


APPLIED    ANATOMY 


ligament  and  so  luxate  it.  The  supinator  {brevis)  arises  partly  from  the  orbicular 
ligament  and  strengthens  the  joint  somewhat. 

The  external  lateral  ligament  is  a  strong  band  which  is  attached  above  to 
the  lower  portion  of  the  lateral  (external)  condyle,  blends  with  the  orbicular  liga- 
ment and  is  attached  below  to  the  ulna  along  the  anterior  and  posterior  edges  of  the 
lesser  sigmoid  cavity  (Fig.  295). 

The  internal  lateral  ligament  is  a  strong  band  attached  above  to  the  lower 
and  anterior  portion  of  the  medial  (internal)  condyle,  the  groove  beneath,  and 
descends  in  the  shape  of  a  fan  to  insert  into  the  inner  edge  of  the  coronoid  process 
and  olecranon  (Fig.  296). 

The  anterior  ligament  is  capsular  in  its  nature  and  function,  and  is  a  broad, 
comparatively  thin  membrane  which  stretches  between  the  lateral  ligaments  on  the 


Fig.  296. — The  internal  lateral  ligament  of  the  elbow- joint,  showing  its  fan-like  shape. 

sides  and  is  attached  above  to  the  upper  edge  of  the  coronoid  fossa  and  below  to  the 
coronoid  process  and  orbicular  ligament.  It  sometimes  possesses  a  few  coarse  fibres 
passing  downward  and  outward,  but  it  is  mostly  very  thin,  in  places  barely  covering 
the  lining  membrane. 

The  posterior  ligament  resembles  the  anterior.  It  blends  on  each  side  with 
the  lateral  ligaments  and  is  attached  above  across  the  upper  portion  of  the  olecranon 
fossa  and  below  to  the  olecranon  and  posterior  portion  of  the  orbicular  ligament.  It 
also  has  some  cross  fibres;  but,  especially  at  its  upper  attachment,  it  is  very  weak. 


MUSCLES   OF   THE   ELBOW. 

The  elbow-joint  is  interposed  between  the  long  bones  of  the  forearm  below  and 
the  long  humerus  above.  The  arm  muscles  come  down  and  pass  over  the  joint  to 
insert  close  to  it  in  the  bones  of  the  forearm.  The  muscles  of  the  forearm  in  a  similar 
manner  cross  the  joint  and  are  attached  comparatively  near  it  to  the  humerus  above. 
Thus  we  see  the  joint  strengthened  by  the  crossing  of  the  various  muscular  insertions. 
The  elbow  having  only  an  anteroposterior  motion,  the  muscles  must  of  necessity  be  in 
two  main  groups,  one  in  front  and  the  other  behind  the  joint. 

Lateral  Muscles. — It  is  true  that  there  are  lateral  muscles  but  they  have  little 
or  no  influence  on  the  movements  of  the  elbow-joint.  The  medial  (internal)  condyle 
gives  origin  to  the  flexor  muscles  of  the  forearm  and  the  pronator  radii  teres,  and 
the  lateral  (external)  condyle  gives  origin  to  the  extensor  muscles;    but  the  bony 


REGION    OF   THE    ELBOW 


285 


attachment  of  both  these  sets  of  muscles  coincides  too  closely  with  the  axis  of  motion 
to  allow  of  their  aiding  to  any  marked  extent  either  flexion  or  extension  of  the 
elbow.  Their  function  as  far  as  the  elbow  is  concerned  is  to  aid  and  strengthen  the 
lateral  ligaments  of  their  special  sides. 

The  Anterior  or  Flexor  Muscles. — These  comprise  the  biceps,  brachialis 
antiais,  brachioradialis,  and  extensor  carpi  radialis  longior.  It  will  be  observed 
that  the  first  two  muscles  come  from  above  and  cross  the  joint,  while  the  last  two 
arise  just  above  the  joint  to  pass  down  the  forearm  (Fig.  297). 

The  brachialis  anticiis  arises  from  the  humerus  by  two  heads,  one  on  each 
side  of  the  insertion  of  the  deltoid,  and  from  the  anterior  surface  to  just  above  the 


Inner  head  of  triceps 


Flexor  carpi  ulnaris 


Biceps 


Brachialis  anticus 


Brachioradialis 


Supinator 


Pronator  radii  teres 


Flexor  carpi  radialis 


Palmaris  longus 


Fig.  297. — View  of  the  antecubital  fossa  and  muscles  at  the  bend  of  the  elbow. 

elbow-joint.  It  passes  over  the  joint  and  inserts  into  the  base  or  lower  and  inner 
part  of  the  coronoid  process.  It  does  not  insert  into  the  tip,  but  some  distance 
below.      Its  function  is  purely  flexion. 

The  biceps  arises  from  the  upper  rim  of  the  glenoid  cavity  by  its  long  head  and 
from  the  coracoid  process  by  its  short  head.  It  inserts  into  the  posterior  edge  of  the 
bicipital  tubercle  of  the  radius.  Between  it  and  the  tubercle  is  a  bursa.  About  4  cm. 
( I  ^  in. )  above  its  insertion  its  tendon  gives  off  a  fibrous  expansion  which  passes 
inward  to  blend  with  the  deep  fascia  covering  the  flexor  group  of  muscles.  This  is 
called  the  bicipital  or  semilunar  fascia.  The  biceps  tendon  passes  almost  in  the 
middle  between  the  two  condyles.  Along  its  inner  side  is  the  brachial  artery,  which 
is  covered  by  the  bicipital  fascia;  over  this  fascia  passes  the  median  basilic  vein, 
sometimes  used  for  transfusion.  The  insertion  of  the  biceps  is  into  the  radius,  which 
is  the  movable  bone,  and  not  into  the  ulna,  which  is  less  so.  As  a  consequence,  in 
addition  to  its  function  of  flexion  it  acts  also  as  a  powerful  supinator  of  the  radius. 


286 


APPLIED    ANATOMY. 


The  extensor  carpi  radialis  longwr  arises  from  the  lateral  condyle  and  lower  third 
of  the  supracondyloid  ridge  and  inserts  into  the  base  of  the  second  metacarpal  bone. 

The  brachioradialis  or  supinator  longus  arises  from  the  upper  two-thirds  of  the 
lateral  (external)  supracondyloid  ridge  above  the  preceding  muscle  and  as  high  as  the 
insertion  of  the  deltoid.      It  inserts  into  the  base  of  the  styloid  process  of  the  radius. 

These  two  muscles,  owing  to  their  high  attachment,  so  much  above  the  axis  of 
motion  of  the  joint,  both  act  as  flexors.     The  brachioradialis  also  supinates  the  hand. 

The  Posterior  or  Extensor  Muscles. — These  comprise  the  triceps  and 
anconeus  niiiscles  (Fig.  298). 

The  triceps  arises  by  its  long  head  from  the  lower  part  of  the  rim  of  the  glenoid 
cavity  and  adjoining  border  of  the  scapula;  by  its  external  or  lateral  head  from  the 


Triceps 


Olecranon  process 

Brachioradialis 

Extensor  carpi  radialis  longior 

External  condyle 

Fascial  continuation  of  the  triceps 
inserting  into  the  shaft  of  the  ulna 


Anconeus  muscle  under  the  fascia 


Fio.  298. — Extensor  muscles  of  the  back  of  the  elbow. 


upper  outer  portion  of  the  humerus  from  the  greater  tuberosity  above  to  the  radial 
(musculospiral)  groove  below;  by  its  internal  or  medial  head  from  the  posterior 
surface  of  the  humerus  below  the  radial  groove.  It  inserts  into  the  posterior  part  of 
the  upper  surface  of  the  olecranon.  Just  above  its  insertion  it  is  separated  from  the 
bone  by  a  bursa.  It  is  continuous  from  the  outer  edge  of  the  olecranon  as  a  firm  fascia 
which  passes  down  over  the  anconeus  to  be  attached  to  the  upper  fourth  of  the  ulna 
and  the  deep  fascia.      This  is  an  important  structure  in  fractures  of  the  olecranon. 

The  anconeus  passes  downward  and  backward  from  the  lateral  (external)  condyle 
to  insert  into  the  side  of  the  olecranon  and  upper  fourth  of  the  ulna.  Its  fibres  are 
practically  continuous  with  the  lower  fibres  of  the  triceps  and  it  may  be  considered 
as  a  fourth  head  of  that  muscle.  It  covers  the  posterior  portion  of  the  head  of  the 
radius  and  overlaps  somewhat  the  supinator  (brevis)  muscle. 


REGION    OF    THE    ELBOW. 


287 


SURFACE   ANATOMY. 

Having  become  acquainted  with  the  bones  and  muscles,  one  will  be  better  able 
to  appreciate  the  surface  markings  and  understand  their  significance  (Fig.  299). 

When  the  elbow  is  fully  extended  the  bony  projections  are  obscured  by  the  soft 
tissues,  hence  in  examining  an  elbow  it  should  be  flexed  at  approximately  a  right 
angle.  The  first  object  to  strike  the  eye  is  the  prominent  olecranon  process.  It  is 
subcutaneous  and  the  bony  ulna  beneath  can  be  felt  and  followed  down  the  back  of 
the  forearm.  From  the  tip  upward  for  a  couple  of  centimetres  can  be  felt  the  upper 
surface  of  the  olecranon  into  which  the  triceps  inserts.  To  feel  this  distinctly  the 
forearm  should  be  slightly  extended  to  relax  the  triceps;  the  outline  of  the  upper 
portion  of  the  olecranon  then  becomes  perfectly  distinct. 

Projecting  on  each  side  of  the  elbow  are  the  two  condyles  of  the  humerus. 
These  bony  projections  do  not  belong  to  the  forearm.  The  two  condyles  are  nearly 
on  the  same  level.  The  medial  (internal)  is  much  more  prominent  and  has  the 
appearance  of  being  a  trifle  higher  and  slightly  anterior.     A   line   joining   them 


Tendon  of  triceps  — 


Internal  condyle 
Olecranon  process 


Flexor  carpi  ulnaris 


Brachioradialis  and  extensor  carpi 
■  radialis  longior 


-External  condyle 

Depression,  head  of  radius 
-Anconeus 

_       Extensor  communis  digitorum 
—  Extensor  carpi  ulnaris 
— Subcutaneous  surface  of  ulna 


Fig.  299. — Surface  anatomy  of  the  back  of  the  elbow. 

crosses  the  long  axis  of  the  humerus  at  an  angle  of  90  degrees,  but  makes  an  angle 
of  only  80  degrees  with  the  forearm.  By  deep  pressure  the  lateral  (external)  supra- 
condylar ridge  can  readily  be  felt  running  up  the  arm  somewhat  posteriorly  from 
the  lateral  (external)  condyle.  The  medial  (internal)  supracondylar  ridge  is  much 
less  easily  felt  though  the  intermuscular  septum  is  more  evident  on  this  side.  When 
the  elbow  is  flexed  at  a  right  angle  a  line  drawn  parallel  with  the  humerus  and  pro- 
longed through  the  two  condvles  will  cut  the  tip  of  the  olecranon.  If  the  forearm  is 
extended  the  olecranon  passes  slightly  posterior  to  this  line;  if  the  forearm  is  flexed, 
the  olecranon  passes  somewhat  in  front  of  it.  Hence  in  examining  the  elbow  for 
injury  it  is  desirable  to  determine  the  relation  of  these  points  when  the  elbow  is  bent 
at  a  right  angle.  The  coronoid  process  lies  anteriorly,  deep  in  the  flexure  of  the 
elbow,  and  cannot  be  distinctly  felt. 

If,  now,  the  elbow  is  extended,  the  tip  of  the  olecranon  can  still  be  felt  with  the 
medial  (inner)  condyle  to  its  inner  side.  Between  the  two  is  a  deep  groove  in  which 
lies  the  ulnar  nerve.  To  the  outer  side  of  the  olecranon  is  a  deep  pit  or  short  groove; 
the  bone  marking  its  outer  edge  is  the  lateral  (external)  condyle.  In  the  bottom  of 
this  pit  at  its  lower  portion,  about  2.5  cm.  (i  in.)  below  the  tip  of  the  olecranon,  can 
be  felt  the  head  of  the  radius.     If  the  thumb  is  placed  on  it  and  the  hand  rotated,  the 


288  \MIWHK»         APPLIED    ANATOMY.  "^^^^^OI^M 

head  of  the  radius  can  be  felt  turning  beneath.  Immediately  above  the  head  of  the 
radius,  lying  to  the  outer  side  of  the  olecranon,  if  the  elbow  be  again  flexed  to  a  right 
angle,  can  be  seen  and  felt  the  bony  projection  of  the  capitellum  covered  by  the 
strong  expansion  from  the  triceps.  By  careful  palpation  a  groove  can  be  felt  between 
the  lower  edge  of  the  capitellum  and  the  head  of  the  radius  which  marks  the  limits 
and  point  of  articulation  of  the  two  bones. 

On  the  posterior  aspect  of  the  joint  the  ulnar  nerve  is  the  most  important  struc- 
ture; there  is,  however,  a  bursa  between  the  upper  or  posterior  surface  of  the  olec- 
ranon and  the  skin  and  also  another  on  its  inferior  surface,  extending  downward, 
which  from  its  exposed  position  is  frequently  injured  and  enlarged.  Such  an 
enlargement  occurs  from  chronic  irritation  in  certain  occupations,  hence  the  name 
' '  miners'  elbow. ' ' 

With  the  elbow  flexed  at  a  right  angle  there  is  seen  on  its  anterior  surface  a 
crease  which  runs  from  one  condyle  across  to  the  other.  If  a  knife  were  held  parallel 
with  the  forearm  and  entered  at  this  crease,  it  would  strike  the  humerus  above  the 
level  of  the  joint  line,  that  is,  the  line  of  contact  of  the  bones.  This  joint  line  runs 
from  1.25  cm.  (^  in.)  below  the  lateral  (external)  condyle  to  2.5  cm.  (i  in.)  below 
the  medial  (internal)  condyle. 

Anteriorly  the  muscular  masses  form  prominent  landmarks.  In  the  middle  of 
the  crease  can  be  felt  the  tendon  of  the  biceps  muscle.  The  muscular  swell  above 
the  crease  is  formed  by  the  biceps  muscle  with  the  brachialis  anticus  beneath.  The 
sharp  upper  edge  of  the  bicipital  fascia  can  be  distinctly  felt  when  the  muscle  con- 
tracts. The  limits  of  the  biceps  can  be  felt  as  two  lines,  radiating  like  the  letter  V 
from  the  biceps  tendon  upward.  These  are  the  commencing  bicipital  furrows  or 
grooves. 

The  outer  branch  marks  the  depression  between  the  outer  edge  of  the  biceps  and 
the  swell  forming  the  supinator  group  of  muscles.  The  inner  branch  marks  the  inner 
edge  of  the  biceps,  and  between  it  and  the  medial  condyle  can  be  felt  a  muscular 
mass  which  is  formed  by  the  inner  portion  of  the  brachialis  anticus.  In  the  middle 
of  the  flexure  of  the  elbow  below  the  crease  is  a  depression  called  the  anteczibital fossa. 
To  its  outer  side  is  the  muscular  prominence  of  the  extensors  and  supinator.  To  its 
inner  side  is  the  muscular  prominence  of  the  flexors  and  pronator.  The  inner  mus- 
cular swell  ends  at  the  medial  (internal)  condyle,  but  the  external  one  passes  well  up 
on  the  arm.  The  muscles  so  prolonged  upward  are  the  extensor  carpi  radialis  longior 
for  about  5  cm,  (2  in.)  above  the  lateral  (external)  condyle,  and  the  brachioradialis 
(supinator  longus)  for  10  cm.  (4  in.)  higher.  The  outer  limit  of  the  antecubital  fossa 
is  formed  by  the  inner  edge  of  the  brachioradialis.  The  inner  side  is  formed  by  the 
pronator  radii  teres  muscle. 

To  the  inner  side  of  the  biceps  tendon  lies  the  brachial  artery,  which  bifurcates 
opposite  the  neck  of  the  radius,  approximately  2  cm.  or  a  finger's  breadth  below  the 
crease  of  the  elbow.  Still  farther  to  the  inner  side  lies  the  median  nerve.  In  the 
groove  between  the  biceps  and  brachialis  anticus  on  the  inner  side  and  brachio- 
radialis (supinator  longus)  and  extensor  carpi  radialis  longior  on  the  outer  side  lies 
the  radial  (musculospiral)  nerve;  it  divides  above  or  opposite  the  lateral  (external) 
condyle  into  the  superficial  branch  and  posterior  interosseous  nerve 

THE  VEINS   OF   THE   ELBOW. 

The  flexure  of  the  elbow  is  occupied  by  a  number  of  veins  which  are  of  impor- 
tance from  the  fact  that  they  are  frequently  used  for  purposes  of  saline  infusion, 
sometimes  for  blood-letting,  and  not  infrequently  they  are  wounded  and  give  rise  to 
troublesome  hemorrhage. 

They  are  made  more  prominent  by  allowing  the  arm  to  hang  and  by  tying  a 
bandage  firmly  above  the  elbow.  The  larger  part  of  the  blood  from  the  parts  below 
is  carried  by  the  superficial  veins;  hence  the  largest  veins  lie  directly  beneath  the  skin 
and  can  be  seen  through  it. 

Their  arrangement  is  not  always  regular  but  they  follow  a  more  or  less  general 
plan.  The  blood  from  the  radial  side  of  the  wrist  and  forearm  is  carried  by  the  radial 
vein.     The  median  vein  brings  the  blood  from  the  anterior  surface  of  the  wrist  and 


REGION    OF   THE    ELBOW. 


289 


parts  abo\'e.  There  are  two  veins  on  the  ulnar  side,  an  anterior  and  a  posterior.  The 
anterior  carries  the  blood  from  the  anterior  ulnar  aspect  and  the  posterior  ulnar  from 
the  posterior  ulnar  aspect  of  the  wrist  and  forearm.  All  these  veins  contain  valves 
at  intervals  of  a  few  inches.  The  median  vein  passes  up  the  middle  of  the  anterior 
surface  of  the  forearm,  and  just  below  the  lower  edge  of  the  bicipital  fascia  communi- 
cates with  the  deep  veins  accompanying  the  radial  and  ulnar  arteries.  This  commu- 
nication is  large,  distinct,  and  always  present  (Fig.  300). 

The  median  vein  then  divides  into  the  median  basilic,  which  passes  upward  in 
the  internal  bicipital  furrow,  and  the  median  cephalic,  which  follows  the  edge  of  the 


Median  nerve 


Basilic  vein 

Ulnar  nerve 

Triceps  muscle 


Internal  cutaneous 
(antibrachii  medialis)  nerve 


Brachialis  anticus   muscle 


Posterior  ulnar  vein * 


Anterior  ulnar  vein 


Bicipital  fascia 


Brachial  artery- 


Biceps  muscle 


Median  basilic  vein 


Median  cephalic  vein 


Musculocutaneous 
nerve      (antibrachii 
lateralis) 

Communication 
between  the  deep  and 
superficial  veins 

Radial  vein 


Median  vein 


Fig.  300. — Veins  at  the  bend  ot  the  elbow. 


biceps  to  the  external  bicipital  furrow.  Three  or  four  centimetres  above  the  bifurca- 
tion of  the  median,  the  median  cephalic  vein  is  joined  by  the  radial,  and  from  that 
point  up  it  is  called  the  cephalic  vein. 

The  two  ulnar  veins  just  below  the  medial  (internal)  condyle  or   sometimes 

just  above  it  empty  into  the  median  basilic  vein,   which  from  this  point  is  called 

the  basilic  vein.     Sometimes  the  two  ulnar  veins,  anterior  and  posterior,  unite  and 

empty  into  the  median  basilic  by  a  common  trunk.      The  median  basilic  vein  passes 

19 


290 


APPLIED    ANATOMY. 


over  the  bicipital  fascia,  which  separates  it  from  the  brachial  artery  which  lies  directly 
beneath.  The  median  basilic  \ein  (or  cephalic  when  more  prominent)  is  usually 
chosen  for  purposes  of  saline  infusion.  It  lies  to  the  inner  side  of  the  biceps  tendon 
and  no  important  structures  are  liable  to  be  wounded.  The  terminal  filaments  of 
the  musculocutaneous  nerve  pass  under  the  median  cephalic  vein  and  are  not  liable 
to  be  wounded.  If  the  median  basilic  is  chosen  for  infusion  or  venesection  care  must 
be  taken  not  to  cut  through  the  bicipital  fascia,  otherwise  a  wound  of  the  brachial 
artery  may  be  produced  which  may  result  in  the  formation  of  a  varicose  aneurism  or 
aneurismal  varix. 

When  these  veins  are  wounded  the  bleeding  may  be  very  free.  Not  only  are 
the  superficial  parts  drained  but  likewise  the  deep  parts  through  the  communication 
with  the  median.  We  saw  one  case  in  which  death  nearly  resulted  from  such  a 
wound  made  by  a  piece  of  tin.  When  saline  infusion  is  practised  the  vein  selected 
is  made  visible  by  compressing  it  above.  It  is  then  cut  directly  down  upon  and 
isolated,  and  the  cannula  inserted. 

BRACHIAL   ARTERY. 


At  the  bend  of  the  elbow  the  artery  lies  to  the  inner  side  of  the  biceps  tendon. 


It  is  beneath  the  bicipital  or  semilunar  fascia, 
felt  opposite  the  crease.  In  the  lower  third 
of  the  arm  the  median  nerve  lies  close 
to  the  artery,  but  as  the  bend  of  the  elbow 
is  reached  it  diverges  and  becomes  sepa- 
rated from  it  by  the  coronoid  head  of  the 
pronator  radii  teres  muscle.  Superficial  to 
the  deep  fascia  is  the  median  basilic  vein, 
crossed  at  its  upper  portion  by  the  cuta- 
neous antebrachii  medial  is  (internal  cuta- 


The  upper  edge  of  this  fascia  can  be 


m 


Superior  profunda  (A.  profunda 
brachii) 

■  Brachial  artery 

Inferior  profunda  (coUateralis 
ulnaris  superior) 


Internal  condyle 

Median  nerve 

Venae  comites 

Brachial  artery 

Biceps  tendon 


;^ 


Anastomotica  magna  (collate- 
"ralis  ulnaris  inferior) 


-Radial  recurrent 
-Ulnar  recurrent 


Jnterosseous  recurrent 
-Posterior  interosseous 
"Anterior  interosseous 

Radial  artery 
-Ulnar  artery 


I 


Fig.  301. — Ligation  of  the  brachial  artery  at  the  bend 
of  the  (left)  elbow. 


Fig.  302. — Collateral  circulation  after  ligation  of  the 
brachial  artery  at  the  bend  of  the  elbow. 


neous)  nerve.  The  bifurcation  of  the  brachial  artery  occurs  opposite  the  neck  of  the 
radius,  which  is  approximately  a  finger's  breadth,  or  about  2  cm.,  below  the  crease  of 
the  elbow. 

Ligation  of  the  Brachial  Artery  at  the  Bend  of  the  Elbow. — The  inci- 
sion is  laid  along  the  inner  edge  of  the  biceps  tendon.  The  median  basilic  vein  is 
usually  more  prominent  than  the  median  cephalic  and  can  be  seen  obliquely  crossing 


REGION    OF   THE    ELBOW.  291 

the  artery  to  reach  its  inner  side.  This  vein  is  encountered  as  soon  as  the  skin  is 
divided,  hence  care  is  necessary  to  avoid  wounding  it.  It  should  be  displaced  to  the 
inner  side  along  with  a  filament  of  the  cutaneous  nerve  if  this  is  present.  The  inci- 
sion is  then  deepened  through  the  upper  portion  of  the  bicipital  fascia  and  the  artery 
found  beneath,  lying  in  loose  fatty  tissue  and  accompanied  by  two  venae  comites. 
The  median  nerve  lies  to  the  inner  side  but  may  be  sufficiently  removed  not  to  be 
exposed.     The  needle  is  passed  from  the  inner  towards  the  outer  side  (Fig.  301). 

Collateral  Circulation. — On  the  outer  side  the  profunda  (superior)  anastomoses 
with  the  interosseous  recurrent  (a  branch  of  the  posterior  interosseous)  and  radial 
recurrent.  On  the  inner  side  the  superior  ulnar  collateral  (inferior  profunda)  and 
inferior  ulnar  collateral  (anastomotica  magna)  anastomose  with  the  anterior  and 
posterior  ulnar  recurrent  arteries  (Fig.  302). 

DISLOCATIONS   OF   THE   ELBOW. 

In  dislocation  of  the  elbow  the  bones  of  the  forearm  are  most  commonly  displaced 
backward.  More  rarely  they  may  be  partially  displaced  either  inwardly  or  outwardly 
and  with  or  without  an  accompanying  backward  displacement.     The  lateral  ligaments 


External  condyle 
of  humerus 


Head  of  radius 


Olecranon 
Fig.  303. — Posterior  luxation  of  the  elbow;  surface  view  of  the  outer  side. 

are  strong,  the  anterior  and  posterior  weak.  The  formation  of  the  bones  permits 
anteroposterior  movement  and  resists  lateral  movement;  hence  the  frequency  of 
anteroposterior  and  the  rarity  of  lateral  luxations.  To  understand  and  recognize  these 
dislocations  and  distinguish  between  them  and  fractures  requires  a  knowledge  of  the 
shape  of  the  bones,  the  position  of  the  articulations,  and  especially  of  the  relations 
and  significance  of  the  various  bony  prominences,  in  other  words,  surface  anatomy. 
In  doubtful  cases  compare  the  normal  with  the  injured  elbow. 

Backward  Dislocation  of  the  Elbow. — In  backward  dislocation  the  radius 
and  ulna  are  pushed  backward  and  the  lower  end  of  the  humerus  comes  forward.  It 
is  most  commonly  caused  by  falls  on  the  outstretched  hand  and  not  by  direct  injury 
to  the  elbow. 

On  the  cadaver  hyperextension  with  or  even  without  a  slight  twisting  readily 
produces  the  displacement. 

The  internal  and  external  lateral  ligaments  are  torn  loose  from  their  respective 
condyles  and  the  anterior  ligament  is  ruptured.      The  posterior  ligament  is  stretched 


ag2 


APPLIED    ANATOMY 


from  the  olecranon  process  to  the  humerus,  and  with  the  periosteum  may  be  hfted 
up  but  not  ruptured.  This  is  especially  the  case  with  the  periosteum  above  the 
external  condyle,  as  shown  by  Stimson. 

The  amount  of  tearing  of  the  muscles  depends  on  the  amount  of  displacement. 
The  flexor  muscles  may  be  partly  torn  from  the  internal  condyle  or  the  extensors 
from  the  external.  The  brachialis  anticus  probably  will  be  somewhat  torn  near  its 
insertion  in  front  of  the  coronoid  process.  The  biceps  is  not  torn  but  may  in  some 
cases  be  caught  behind  the  external  condyle.  The  orbicular  ligament  remains  intact 
and  holds  the  radius  in  its  proper  relation  to  the  ulna. 

Signs. — The  position  assumed  by  the  bones  is  usually  one  of  slight  flexion, 
approximately  120  degrees  (Hamilton). 

Viewing  the  elbow  from  the  side,  the  anterior  portion  of  the  arm  above  the  crease 
is  fuller  than  is  normally  the  case.  Posteriorly  the  olecranon  is  seen  projecting,  and 
above  it  is  a  distinct  hollow.  On  the  outer  side  of  the  joint  immediately  in  front  of 
the  olecranon  is  seen  a  prominent  projection  caused  by  the  head  of  the  radius.      It  is 


Internal  condyle  of    humerus 


Prominence  formed   by  the   trochlea  of  the 
lower  end  of  the  humerus 


Olecranon 
Fig.  304. — Posterior  luxation  of  the  elbow;  surface  view  of  the  inner  side. 

to  be  recognized  by  placing  the  thumb  on  it  and  rotating  the  hand.  Almost  directly 
above  it  may  be  felt, — though  it  is  not  at  all  distinct, — the  external  condyle  (Figs.  303 
and  305  ) .  On  the  inner  side  are  seen  two  rounded  bony  eminences.  The  posterior  and 
upper  of  these  is  the  larger;  it  is  the  internal  condyle.  Below  and  anterior  to  this  is 
another;  it  is  the  inner  edge  of  the  trochlear  articulating  surface  (Figs.  304  and  306). 

Measurements  from  the  condyle  to  the  acromion  process  show  that  they  are  the 
same  on  the  injured  and  the  healthy  sides.  Measurements  from  the  condyle  to  the 
styloid  process  of  the  ulna  show  shortening  on  the  injured  side.  As  the  lateral  liga- 
ments are  torn  there  is  abnormal  lateral  mobility.  If  the  forearm  is  placed  at  right 
angles  to  the  arm,  it  is  seen  that  the  tip  of  the  olecranon  no  longer  lies  on  a  plane 
drawn  through  the  long  axis  of  the  arm  and  the  two  condyles,  but  is  considerably 
posterior  to  it. 

The  diagnosis  as  pointed  out  by  Stimson  should  be  based  on  the  positive  recog- 
nition of  the  position  of  the  olecranon,  the  two  condyles,  and  the  head  of  the  radius. 

Treatment. — The  lower  end  of  the  humerus  rests  in  front  of  the  coronoid  process 
(rarely  fractured).      When  the  forearm  is  flexed  the  triceps  becomes  tense  and  holds 


REGION    OF   THE    ELBOW. 


'■93 


the  bones  locked  in  their  displaced  position.     The  coronoid  process  prevents  the 
humerus  from  going  back  into  place.      To  reduce  the  dislocation,  the  triceps  is  to  be 


Fig.  305. — Posterior  luxation  of  the  elbow,  showing  the 
position  of  the  bones  as  viewed  from  the  outer  side. 


Fig.  306. — Posterior  luxation  of  the  elbow,  showing  the 
position  of  the  bones  as  viewed  from  the  inner  side. 


relaxed  by  extending  the  forearm  to  an  angle  of  about  120  degrees,  thus  lowering 
the  coronoid  process,  and  extension  is  to  be  made  on  the  forearm  and  counterexten- 
sion  on  the  arm.     Usually  an  anaesthetic  is  not  required  (Fig.  307). 

Inward  Dislocation  of  the  Elbow. — In  inward  dislocation  the  ulna  and 


Median  nerve^ 


Brachialis  anticus 


Tendon  of  triceps 
Ulnar  nerve 

"Olecranon  process 


Coronoid  process 
Pig.  307. — Dissected  preparation  of  posterior  luxation  of  the  elbow,  viewed  from  the  inner  side, 

radius  are  pushed  toward  the  inner  side.     The  head  of  the  radius  leaves  the  capi- 
tellum  to  rest  on  the  adjacent  portion  of  the  trochlea.     The  olecranon  slides  from  the 


294 


APPLIED    ANATOMY. 


outer  to  the  inner  surface  of  the  trochlea.  The  outer  condyle  then  becomes  promi- 
nent while  the  inner  becomes  confused  with  the  olecranon.  The  identity  of  the  con- 
dyles is  always  to  be  established  by  tracing  them  up  the  humerus.  This  dislocation 
is  always  incomplete. 

Treatment. — Extension  and  counterextension  with  the  arm  slightly  flexed  to 


Fig.  308. — Anterior  dislocation  of  the  head  of  the  radius.     (From  author's  sketch.) 


release  the  coronoid  process  aided  by  direct  pressure  on  the  humerus  inward  and  the 
ulna  outward. 

Outward  Dislocation  of  the  Elbow. — In  outward  dislocation  the  concave 
surface  of  the  olecranon  rests  on  the  capitellum  and  in  the  groove  between  it  and  the 
trochlea.  The  head  of  the  radius  projects  far  to  the  outer  side  of  the  external  condyle. 
The  inner  condyle  and  trochlea  become  quite  prominent  and  can  be  readily  recognized. 

Treatme7it. — Slight  flexure  of  the  fore- 
arm. Traction  and  pressure  on  the  radius 
inward  and  on  the  internal  condyle  and 
lower  end  of  the  humerus  outward. 

Dislocation  of  the  Head  of  the 
Radius. — The  ulna  alone  is  rarely  luxated 
(when  displaced  it  would  practically  be 
a  backward  and  inward  luxation  of  the 
elbow)  but  the  head  of  the  radius  is  not 
infrequently  pulled  out  of  place  (Fig.  308). 
The  accident  occurs  in  children,  par- 
ticularly young  ones  who,  in  walking  with 
their  elders,  are  frequently  lifted  or  helped 
along  by  a  pull  on  the  hand.  The  pull, 
accompanied  by  hyperextension  of  the  el- 
bow and  some  adduction  of  the  hand,  draws 
the  head  of  the  radius  from  beneath  the 
orbicular  ligament  and  then  the  tension  of 
the  biceps  drags  it  forward.  The  displace- 
ment may  be  either  marked  or  slight.  A 
marked  displacement  in  the  well-developed 
arm  of  an  adult  is  readily  recognized,  but 
in  the  fat,  chubby,  undeveloped  arm  of  an 
infant  it  is  easily  overlooked. 

Diagnosis. — Pain  attracts  attention  to 
the  part.  There  is  apt  to  be  inability  to 
flex  the  arm  beyond  a  right  angle,  due  to 
the  radius  impinging  on  the  lower  end  of 
the  humerus.  Careful  palpation  reveals  a 
hollow  below  the  lateral  (external)  condyle  which  should  be  normally  occupied  by 
the  head  of  the  radius.  The  outer  side  of  the  forearm  at  the  bend  of  the  elbow  may 
be  abnormally  full  and  pressure  here  may  detect  the  head  of  the  radius  displaced 
forward  (Figs.  309  and  310). 

Treatment.  — The  forearm  is  to  be  extended  almost  to  a  straight  line.  Pressure 
is  to  be  made  with  the  thumb  to  force  the  head  of  the  radius  back  into  place.  While 
this  is  done  the  forearm  is  to  be  flexed  on  the  arm   and  if  the  head  is  replaced  the 


Fig.  309. — Anterior  dislocation  of  the  head  of  the 
radius.    Position  of  bones  when  viewed  from  in  front. 


REGION   OF   THE    ELBOW.  295 

elbow  can  be  bent  to  its  normal  acute  angle.  On  extension  being  made  the  radius 
frequently  again  jumps  forward,  hence  the  injury  is  to  be  subsequently  treated  with 
the  arm  in  a  flexed  position. 


Brachialis  anticus 
Biceps  tendon 


External  condyle 

External  lateral  liga- 
ment 

Orbicular  ligament 


Ulna 
Fig.  310. — Anterior  luxation  of  the  head  of  the  radius. 

FRACTURES   IN   THE   REGION   OF  THE   ELBOW. 

The  elbow  is  frequently  the  seat  of  fractures,  especially  in  children.  Their 
diagnosis  and  treatment  are  both  difficult  and  the  result  sometimes  unsatisfactory. 

The  bony  processes  are  less  distinct  in  children  than  in  adults  and  fractures 
sometimes  pass  unrecognized,  being  considered  sprains,  until  the  persistent  disability 
or  marked  deformity  betrays  their  presence.  Luxations  and  fractures  are  at  times 
mistaken  for  one  another.  For  these  reasons  a  working  knowledge  of  the  anatomy  of 
the  region  is  indispensable. 

The  fractures  that  occur  in  this  region  are  transverse  fractures  above  the  con- 
dyles and  oblique  fractures  through  the  condyles,  which  may  either  involve  the  condyles 
proper  (epicondyles  so  called)  and  be  extra-articular,  or  involve  the  articular  surface 
of  the  trochlea  or  capitellum.  Both  condyles  may  be  detached  by  a  T-  or  Y-shaped 
fracture:  the  olecranon  may  be  fractured  and  also  the  head  or  neck  of  the  radius. 

Transverse  Fracture  of  the  Humerus  above  the  Condyles  (Supra- 
condylar).— This  is  the  most  frequent  fracture  of  the  lower  end  of  the  humerus. 
The  mechanism  of  its  production  is  not  settled.  There  is  little  doubt  but  that  it  can 
be  produced  by  hyperextension,  as  the  bone  fractures  at  this  point  when  luxation 
does  not  occur.  Hamilton  regarded  a  blow  on  the  elbow  as  the  cause.  The  line  of 
fracture  runs  transversely  across  the  bone  just  above  the  condyles  and  obliquely 
from  behind  downward  and  forward  (Fig.  311,  page  296). 

Displacemeiit. — The  lower  fragment  is  drawn  upward  and  backward  and  some- 
times there  is  an  angular  lateral  deformity  with  obliteration  of  the  carrying  angle 
(see  page  282). 

Signs.  — The  overriding  of  the  fragment  produces  shortening  of  the  humerus  as 
measured  from  the  acromion  to  the  lateral  (external)  condyle.  The  olecranon  projects 
backward,  causing  a  hollow  above  which  resembles  that  produced  in  backward  lux- 
ation. The  flexure  of  the  elbow  is  fuller  than  normal.  The  relation  of  the  condyles 
to  the  tip  of  the  olecranon  is  not  altered.  The  condyles  may,  however,  lie  posterior 
to  a  line  drawn  down  the  middle  of  the  humerus  in  its  long  axis.  The  sharp  edge  of 
the  lower  fragment  can  sometimes  be  felt  posteriorly. 

Extension  of  the  forearm  causes  the  fragment  to  be  pushed  still  farther  upward. 

Treatment. — There  is  no  single  treatment  that  is  applicable  to  all  cases.  If  the 
arm  is  too  much  extended,  the  biceps  and  brachialis  anticus  are  made  tense,  and 


296 


APPLIED    ANATOMY. 


tension  of  either  the  anterior  or  posterior  muscles  tends  to  favor  overlapping  and  to 
prevent  replacement.  Full  flexion  renders  the  triceps  tense.  To  relax  both  sets  of 
muscles  a  position  at  about  right  angles  is  probably  best. 

Stimson  has  shown  that  gunstock  (angular)  deformity  frequently  follows  this 
injury,  hence  especial  care  should  be  taken  to  guard  against  it.  It  is  caused  by  a 
tilting  of  the  lower  fragment.  Instead  of  a  line  joining  the  condyles  being  at  right 
angles  to  the  long  axis  of  the  humerus,  it  may  be  oblique,  owing  to  one  condyle 
being  higher  than  the  other.  Practically  it  is  not  possible  to  recognize  this  displace- 
ment when  the  arm  is  bent  at  a  right  angle.  The  splints  will  fit  the  part  and  every- 
thing appears  satisfactory,  but  on  removal  of  the  splints  and  extension  of  the  forearm 
it  may  be  found  that  the  carrying  angle  has  been  destroyed  and  that  a  gunstock 
deformity  is  present.  This  accident  is  to  be  avoided  by  extending  the  arm  during 
the  earlier  periods  of  treatment  before  the  fragment  becomes  fixed  by  callus,  and 


Triceps  muscle 
Ulnar  nerve 

Internal  condyle 
Olecranon 


Fig.  311. — Transverse  fracture  of  the  lower  end  of  the  humerus  above  the  condyles.  The  upper  fragment 
is  seen  to  be  displaced  forward  and  the  lower  fragment  with  the  olecranon  is  displaced  backward.  This  posterior 
displacement  is  increased  by  tension  of  the  triceps  muscle. 

seeing  that,  on  extension,  the  forearm  makes  the  same  angle  with  the  arm  as  does 
that  of  the  healthy  side. 

The  common  mode  of  treatment  of  supracondylar  fractures  is  the  use  of  antero- 
posterior splints  with  the  elbow  bent  at  a  right  angle  or  sometimes  acutely  flexed. 

Fractures  Involving  the  Condyles. — The  condyles  (page  280)  have  been 
described  as  the  lateral  bony  projections  of  the  lower  end  of  the  humerus  which  are 
extra-articular.  Therefore  the  trochlea  and  capitellum  are  not  parts  of  the  condyles, 
and  the  epicondyles  are  simply  the  tips  of  the  condyles. 

Bearing  this  in  mind  it  is  evident  that  fractures  involving  the  condyles  may  be 
confined  to  them  and  not  implicate  the  articular  surfaces.  They  are  then  extra-artic- 
ular fractures  of  the  condyles,  or  they  can  with  some  reason  be  called  fractures  of  the 
epicondyles.  Other  fractures  may  not  only  implicate  the  condyles,  but  pass  through 
them  into  the  articular  surfaces.  These  will  be  called  intra-articular  fractures  of  the 
condyles.  The  internal  epicondyle  (epicondylus  medialis)  is  sometimes  called  the 
epitrochlea. 

Extra-artiailar  Fractures  of  the  Condyles  or  Fractures  of  the  Epicondyles. — The 
medial  (internal)  condyle  projects  far  beyond  the  body  of  the  bone  as  a  distinct  bony 


REGION    OF   THE    ELBOW.  297 

process,  while  the  lateral  (external)  condyle  is  low,  flat,  and  not  prominent.  For 
these  reasons  fractures  of  the  medial  condyle  not  involving  the  joint  are  more  common 
than  those  of  the  lateral  condyle.  In  fact  e.xtra-articular  fractures  of  the  lateral  con- 
dyle (detachment  of  the  epicondyle)  are  almost  unknown,  but  they  have  been  proven 
to  exist. 

In  extra-articular  fractures  of  the  medial  condyle,  the  fragment  has  been  dis- 
placed downward  by  the  flexor  muscles  which  arise  from  it.  To  counteract  this 
tendency  the  arm  is  treated  in  a  flexed  position.  As  the  ulnar  nerve  runs  in  the 
groove  on  the  posterior  surface  of  the  condyle  it  has  also  been  injured,  and  vesicles 
and  impairment  of  sensation  in  the  course  of  the  nerv^e  have  been  observed.  As 
the  articular  surfaces  are  not  involved,  no  serious  deformity  or  disability  need  be 
expected. 

Intra-articular  Fractures  of  the  Condyles. — The  line  of  fracture  in  these  injuries 
usually  starts  above  the  epicondyle  and  passes  toward  the  middle  of  the  bone, 
chipping  off  a  portion  of  the  trochlear  surface  or  the  capitellum.  Fractures  invoh'ing 
the  lateral  are  probably  more  frequent  than  those  involving  the  medial  condyle. 

Intra-articidar  Fracture  of  the  Medial  Condyle. — The  line  of  fracture  passes 
obliquely  through  the  condyle,  entering  just  above  its  tip  and  emerging  on  the  artic- 
ular surface  of  the  trochlea  either  in  the  groove  sepa- 
rating the  two  portions  of  the  trochlea  or  the  groove 
between  the  trochlea  and  capitellum.  As  already  ex- 
plained (page  282),  the  integrity  of  the  joint  and  the 
line  of  the  arm  depend  on  the  trochlea  and  not  on 
the  capitellum,  therefore  the  farther  over  toward  the 
capitellum  the  line  of  fracture  goes  the  more  likely  is 
there  to  be  lateral  mobility  (Fig.  312). 

The  fragment  may  be  pushed  up;  this  carries  the 
ulna  up  with  it  while  the  radius  is  prevented  from 
following  by  the  capitellum.  Therefore  the  forearm 
bends  inward,  making  a  lateral  deformity.  The  carry- 
ing angle  (page  282)  becomes  obliterated  and  what  is 

known  as  gunstock  deformity  or  cubittis  varus  is  pro-       

duced.      It  is  mainly  to  the  researches  of  Dr.  O.  H.  pio.  312.— Fracture  of  internal 

Allis  that  we  are  indebted  for  our  knowledge  of  the       condyle  and  trochlea  causing  gun- 

.     ,  .       ,    .  .  _,,  ,       "^  ,  stock     detormitv     (cubitus     varus). 

mechanism  of  this  deformity.      1  he  attachment  of  the       From  a  photograph  of  a  preparation 

n  1         J  ^1  it.      r  i.  r  •    •  in  the  Mutter    Museum   of   the   Col- 

flexor  muscles  does  not  keep  the  fragment  from  rising.        lege  of  Physicians. 
The  deformity  is  difficult  to  detect  when  the  elbow  is 

flexed.  The  condyles  and  olecranon  and  shaft  of  the  humerus  may  all  be  in  the 
same  straight  line  and  still  the  medial  (internal)  condyle  be  higher  than  normal.  If 
the  injury  is  treated  with  a  right-angled  splint  the  radius  and  ulna  remain  in  their 
proper  positions  but  the  ulna  and  medial  condyle  may  both  be  higher  than  normal. 
If  this  is  the  case,  then,  when  the  forearm  is  extended,  instead  of  it  making  an  angle 
of  10  degrees  outwardly  with  the  line  of  the  humerus,  it  may  incline  10  degrees  or 
even  20  degrees  inwardly:  thus  it  may  deviate  as  much  as  30  degrees  from  the  normal 
direction.  To  guard  against  this  deformity  Allis  advised  treating  the  injury  with  the 
arm  in  full  extension.  Any  tendency  to  lateral  deformity  will  then  be  at  once  evident 
and  can  be  corrected  by  additional  lateral  support.  Certain  it  is  that  no  serious 
fracture  of  the  elbow  ought  to  be  treated  without  frequent  examinations  of  the  arm 
in  full  or  almost  complete  extension  being  made  from  time  to  time,  so  as  to  be  sure 
this  deformity  is  not  becoming  established. 

The  treatment  of  fractures  involving  the  joint  by  placing  the  elbow  in  a  position 
of  complete  flexion  has  been  strongly  advocated  and  as  a  rule  is  best,  although  it  has 
not  entirely  superseded  other  methods  in  all  cases. 

Intra-articnlar  Fracture  of  the  Lateral  {Fxternal)  Condyle. — This  is  also  a  fairly 
common  injury.  The  line  of  the  fracture  passes  from  above  the  tip  of  the  lateral 
condyle  down  into  the  joint  through  the  capitellum  or  between  it  and  the  trochlea. 
As  is  to  be  expected,  this  does  not  show  the  same  tendency  to  lateral  deformity 
as  does  fracture  of  the  trochlea.  When  lateral  deformity  does  occur  it  is  be- 
cause the  fracture  is  so  extensive  as  to  also  involve  the  trochlea.     This,   like  the 


APPLIED    ANATOMY 


other  fractures  of  this  region,  is  to  be  diagnosed  by  grasping  the  fractured  part  and 
detecting  crepitus  and  excessive  mobihty.  The  medial  (internal)  condyle  is  felt 
firmly  attached  to  the  humerus  and  the  olecranon  to  the  ulna,  but  the  lateral  (ex- 
ternal) condyle  is  felt  to  move  independently  of  the  others.  It  is  efficiently  treated 
by  an  anterior  (not  internal)  angular  splint. 

Intercondylar  or  T  Fracture. — When  both  condyles  are  detached  there  is 
produced  what  is  known  as  a  T  fracture.  In  this  injury  both  condyles  are  detached 
from  each  other  and  from  the  shaft  of  the  humerus.  The  line  of  fracture  may  vary. 
Sometimes  there  is  a  transverse  fracture  above  the  condyles  with  a  second  line 
passing  longitudinally  into  the  joint  like  the  letter  T.  In  other  cases  the  lines  may 
be  like  the  letter  V  or  Y  (Fig.  313). 

In  all  these  cases  the  mobility  is  very  marked  and  the  limb  can  be  bent  at  the 
elbow  in  any  direction.  The  diagnosis  is  to  be  made  by  grasping  the  shaft  of  the 
humerus  with  one  hand  and  moving  each  condyle  separately  with  the  other.  Having' 
determined  that  each  is  detached  from  the  humerus,  then 
one  condyle  is  grasped  in  each  hand  and  they  are  moved 
on  one"  another,  thus  establishing  the  fact  of  a  fracture 
between  them. 

In  treatment  the  same  care  must  be  exercised  to  detect 
the  occurrence  of  gunstock  deformity  as  has  already  been 
advised  in  fractures  of  the  medial  condyle.  In  these  frac- 
tures the  fragments  are  frequently  rotated  on  one  another, 
and  disability  and  deformity  so  often  result  that  in  some 
cases  it  is  advisable  to  fix  the  fragments  in  place  by  some 
operative  means. 

Fracture  of  the  Olecranon  Process. — The  olecra- 
non process  may  be  fractured  either  close  to  its  extremity 
near  the  insertion  of  the  triceps  tendon,  through  approxi- 
mately the  middle  of  the  greater  sigmoid  cavity,  or  toward 
the  coronoid  process. 

The  second  is  the  more  common.  The  fracture  which 
occurs  nearer  the  insertion  of  the  triceps  is  liable  to  occur 
from  muscular  action,  the  triceps  contracting  and  tearing  off 
the  piece  of  bone  into  which  it  is  inserted.  The  shape  of 
the  process  should  be  noted.  In  the  bottom  of  the  greater 
sigmoid  cavity  near  where  the  process  joins  the  shaft  it  is 
constricted  and  weakened  by  a  groove  which  sometimes 
passes  nearly  or  quite  across  its  surface.  This  is  the 
weakest  point  and  is  most  often  the  site  of  fracture. 

The  triceps  muscle  inserts  not  only  into  the  upper  sur- 
face of  the  olecranon  but  also  along  its  sides.  In  addition 
it  sends  of?  a  fibrous  expansion  to  each  side ;  the  one  to  the 
medial  condyle  is  thin,  but  the  one  to  the  lateral  condyle 
forms  a  broad,  tough,  fibrous  band  which  stretches  from 
the  olecranon  to  the  lateral  condyle  and  passes  down  over  the  anconeus  to  be 
attached  to  the  outer  edge  of  the  upper  fourth  of  the  ulna  (Fig.  314).  In  cases  of 
fracture  the  fragment  is  only  slightly  displaced  upward  by  the  contraction  of  the 
triceps.  The  reason  is  that  the  fibrous  expansion  of  the  triceps  usually  is  not  suffi- 
ciently torn  to  allow  of  the  retraction  of  the  fragment.  The  amount  of  separation  of 
the  fragments  is  directly  proportional  to  the  amount  of  tearing  of  the  lateral  fibrous 
expansion  of  the  triceps  tendon.  By  extending  the  forearm  the  triceps  is  relaxed  and 
by  pushing  the  fragment  down  crepitus  can  often  be  elicited. 

Treatment. — Fracture  of  the  olecranon  process  is  usually  treated  with  the  elbow 
slightly  flexed.  Complete  extension  is  not  commonly  employed.  The  slight  flexion 
allows  for  the  effusion  into  the  joint  and  leaves  the  arm  sufficiently  extended  to  relax 
the  triceps. 

An  adhesive  strip  placed  across  the  back  of  the  elbow  above  the  fragment  and 
brought  down  and  crossed  on  the  front  of  the  forearm  usually  suffices  to  keep  the 
fragment  in  position.  . 


Fig.  313.  —  Intercondylar 
or  T  fracture  of  the  lower 
end  of  the  humerus.  Mutter 
Museum,  College  of  Physicians. 


REGION   OF   THE    ELBOW. 


299 


The  bond  of  union  between  the  fragments  is  usually  so  short  that  it  appears  to 
be  bony  and  function  is  perfect.  If  the  fibrous  band  is  long  extension  will  be  incom- 
plete and  weak. 

Fracture  of  the  Coronoid  Process  and  Upper  End  of  the  Radius. — 
Fracture  of  the  coronoid  process  does  occur  but  it  is  exceedingly  rare.  The  brachi- 
alis  anticus  does  not  insert  into  its  tip,  but  at  the  lower  part  of  its  anterior  surface. 
The  fracture  is  most  liable  to  occur  in  cases  of  luxation,  the  process  being  knocked 
of?  as  the  humerus  comes  forward. 

Fractures  of  the  Head  and  Neck  of  the  Radius. — The  head  and  neck  of  the 
radius  are  rarely  fractured.     When  broken,  the  line  of  fracture  through  the  head  is 


Ulnar  nerve 


Internal  condyle  ~7^ 


Site  of  fracture  of  olecranon 


Posterior  surface  of  the 
upper  end  of  the  ulna 


Triceps  extensor  muscle 


Portion  of  tendon  of  triceps  which 
inserts  into  the  olecranon  process 


External  condyle  of  humerus 


Portion  of  the  tendon  of  the  triceps 
which  inserts  into  the  posterior 
surface  of  the  upper  fourth  of  the 
ulna 


Fig.  314. — Fracture  of  the  olecranon  process,  showing  the  insertion  of  the  triceps  muscle  into  the  olecranon  and 

upper  fourth  of  the  ulna. 

usually  longitudinal  and  a  portion  of  the  head  is  chipped  off.  The  fragment  is  liable 
to  become  displaced,  and  either  creates  inflammation  and  suppuration  or  becomes 
fixed  and  greatly  interferes  with  motion.  For  these  reasons  the  fractured  head  has 
been  frequently  excised.  A  similar  displacement  may  occur  when  the  neck  of  the 
radius  is  fractured. 

In  this  latter  injury  an  anterior  angular  deformity  is  said  to  have  been  produced 
by  the  action  of  the  biceps  pulling  the  lower  fragment,  to  which  it  is  attached, 
forwards. 

The  classical  specimen  in  the  Mutter  Museum  of  the  College  of  Physicians  of 
Philadelphia  is  usually  instanced  as  an  example  of  this  action.  The  possibility  of  its 
occurrence  suggests  the  treatment  of  the  injury  with  the  elbow  flexed  to  relax  the 
biceps  muscle. 

Epiphyses  of  the  Bones  of  the  Elbow. — Traumatic  epiphyseal  separations 
are  possible,  but  so  rare  as    to    be  seldom  detected.     Supracondylar  fractures  in 


300 


APPLIED    ANATOMY. 


children,    though   not  infrequently   described  as    separations   of   the   epiphysis   are 

probably  more  often  true  bony  fractures. 

Hufucrus. — The  lower  end  of  the  humerus  ossifies  by  four  centres.      Three  of 

them,  those  for  the  lateral  (external)  condyle,  capitellum  and  outer  portion  of  the 

trochlea,  and  inner  portion  of  the  trochlea,  appear  at  the  twelfth,  third,  and  twelfth 

years  and  fuse  and  unite  with  the  shaft  at  about  the  six- 
teenth year.  The  fourth,  for  the  internal  condyle,  appears 
at  the  fifth  and  unites  about  the  seventeenth  or  eighteenth 
year.  The  epiphyseal  line  runs  close  to  the  edge  of  the 
articular  surface  and  is  below  the  level  of  a  transverse  line 
joining  the  upper  edges  of  the  two  condyles  (Fig.  315). 
A  true  epiphyseal  separation  would  thus  be  intra-articular 
and  would  involve  comparatively  only  a  thin  shell  of  the 
articular  surface.  As  already  stated  most  of  the  cases 
regarded  as  epiphyseal  separations  are  probably  true 
supracondylar  fractures. 

Destruction  or  removal  of  the  epiphyseal  cartilage 
is,  of  course,  if  possible,  to  be  avoided  in  operations  in 
young  children,  as  otherwise  interference  with  the  growth 
of  the  bone  will  occur. 

U/na. — Most  of  the  olecranon  process  is  a  direct 
outgrowth  from  the  shaft  of  the  ulna.  At  about  the 
tenth  year  a  thin  shell  forms  at  its  extremity  which 
unites  at  the  sixteenth  year.  Therefore  fractures  which 
pass  through  the  bottom  of  the  greater  sigmoid  caxity 
are  not  separations  of  the  epiphysis  but  true  fractures. 

Radius. — The  upper  articular  surface  of  the  radius 
has  a  centre  of  ossification  which  appears  from  the  fifth 
to  the  seventh  year,   and  unites  at  the   eighteenth  to 
twentieth  year. 
There  is  also  a  centre  for  the  tubercle.      Surgical  writers  as  a  rule  do  not  speak 

of  epiphyseal  separations  of  the  upper  ends  of  the  radius  and  ulna. 

DISEASE   OF   THE   OLECRANON   BURSA. 

Between  the  skin  covering  the  olecranon  process  and  the  bone  is  a  bursa, 
which,  from  its  exposed  position,  is  not  infrequently  diseased.  It  lies  in  the  subcu- 
taneous tissue  and  resembles  in  all  respects  the  bursa  in  front  of  the  patella.  In  those 
whose  occupation  causes  them  to  rest  frequently  on  the  elbow,  this  bursa  becomes 
enlarged,  hence  the  name  ' '  miner's  elbow. ' '  The  bursa  lies  on  the  posterior  surface 
of  the  bone  and  extends  from  the  tip  of  the  olecranon  downward  in  the  direction  of 
the  forearm.  Excision  is  the  most  efficient  treatment.  There  are  no  dangerous 
structures  to  be  encountered  in  the  operation  because  the  bursa  does  not  communi- 
cate with  the  joint.  The  position  of  the  ulnar  nerve  should  be  borne  in  mind.  It 
can  readily  be  avoided  and  usually  is  not  seen.  There  is  sometimes  another  bursa 
on  the  upper  surface  of  the  olecranon  just  below  the  insertion  of  the  triceps.  It  is 
rarely  affected. 

DISEASE   OF   THE  ELBOW-JOINT. 

The  elbow-joint,  like  others,  is  affected  with  rheumatoid  and  tuberculous  dis- 
ease. The  former  frequently  causes  ankylosis,  while  the  latter  frequently  causes 
suppuration.  The  joint  becomes  distended  and  enlarged.  The  bony  prominences 
of  the  elbow,  while  they  may  not  be  visible,  nevertheless  can  usually  be  recog- 
nized by  palpation.  The  lateral  ligaments  are  stronger  than  the  anterior  and  pos- 
terior, hence  the  swelling  is  most  marked  in  front  and  behind.  As  the  internal  lateral 
ligament  is  stronger  than  the  external  lateral,  swelling  will  be  more  marked  on  the 
outer  side  and  the  medial  (internal)  condyle  will  be  more  easily  recognized  than  the 
lateral  (external). 


Fig.  315.  —  Epiphysis  of  the 
lower  end  of  the  humerus;  unites 
with  the  shaft  at  about  the  seven- 
teenth or  eighteenth  year. 


REGION    OF   THE    ELBOW. 


301 


Pus  first  works  its  way  posteriorly  up  behind  the  tendon  of  the  triceps  and  then 
sideways  and  along  the  intermuscular  septa.  As  the  external  supracondylar  ridge  is 
nearer  the  surface  than  the  internal,  pus  will  show  itself  sooner  above  the  lateral 
(external)  condyle.  It  may  form  a  protrusion  on  each  side  of  the  triceps  tendon  and 
olecranon  process. 

Later  it  may  show  itself  anteriorly  ;  when  it  does  so  it  appears  more  to  the  outer 
than  to  the  inner  side,  being  deflected  outwardly  through  the  antecubital  space  by 
the  attachment  of  the  brachialis  anticus  to  the  coronoid  process,  by  the  tendon  of  the 
biceps  and  by  the  bicipital  fascia  which  passes  from  the  tendon  over  the  muscles 
attached  to  the  medial  (internal)  condyle. 

RESECTION    OF   THE   ELBOW. 

A  straight  incision  is  made  over  the  point  of  the  olecranon  a  little  internal  to  its 
middle.      The  upper  portion  of  this   incision  splits  the  triceps.      Its  lower  part  is 


Ole 


Head  of  radius 


Capitellum 
-Trochlea 

Internal  condvle 


Cut  edge  of  capsule 

Ulnar  nerve 

Cut  edge  of  triceps  tendon 


Fig.  316. — Resection  of  the  elbow- joint;  the  ends  of  the  bones  are  exposed  ready  to  be  removed. 

carried  down  to  the  bone  on  the  posterior  surface  of  the  ulna.  The  attachment  of 
the  triceps  to  the  inner  side  is  then  dissected  off  and  the  ulnar  nerve  raised  from  its 
groove  without  injuring  it.  The  medial  (internal)  condyle  is  then  to  be  cleared  of 
the  muscles  attached  to  it.  The  parts  external  to  the  incision  are  now  to  be  raised. 
By  means  of  periosteal  elevators  aided  by  the  knife  the  external  part  of  the  triceps  is 
detached  from  the  bone  as  closely  as  possible,  following  exactly  the  edge  of  the  ulna. 
The  anconeus  is  raised  with  the  triceps  and  the  broad  fibrous  expansion  passing  from 
the  olecranon  to  the  lateral  (external)  condyle  and  thence  over  the  anconeus  to  be 
continuous  with  the  deep  fascia  is  preserved  intact.  On  the  care  with  which  this  is 
done  depends  the  amount  of  subsequent  muscular  control.  As  the  triceps  is  turned 
aside  the  muscles  attached  to  the  lateral  condyle  are  raised  in  the  same  manner.  The 
soft  parts  being  drawn  to  each  side  the  bones  are  protruded  and  the  remaining  soft 
parts  anteriorly  can  be  detached.  A  flat  spatula  is  then  passed  beneath  the  bones 
and  the  humerus  sawed  through  opposite  the  upper  edge  of  the  medial  (internal) 
condyle  above  and  the  radius  and  ulna  opposite  the  lower  edge  of  the  head  of  the 
radius  below.      The  insertions  of  the  biceps  and  brachialis  anticus  are  not  disturbed. 


APPLIED    ANATOMY. 

In  raising  the  supinator  (brevis)  from  the  upper  portion  or  the  radius  care 
should  be  exercised  not  to  wound  the  posterior  interosseous  nerve.  It  runs  between 
two  planes  of  muscular  fibres  in  the  substance  of  the  supinator  (brevis).  It  is  a 
nerve  of  motion  supplying  all  the  extensor  muscles  with  the  exception  of  the  anco- 
neus, brachioradialis  (supinator  longus),  and  extensor  carpi  radialis  longior;  hence 
its  injury  will  be  followed  by  serious  paralysis.  Almost  no  vessels  require  ligation 
(Fig.  316). 

AMPUTATION   AT   THE    ELBOW-JOINT. 

Amputation  at  this  joint  is  peculiar  from  the  fact  of  the  width  of  the  lower  end  of 
the  humerus.  The  skin  is  loose  and  shows  a  marked  tendency  to  retract,  especially  on 
the  anterior  surface.     This,  combined  with  the  large,  expanded  end  of  the  humerus, 


Tendon  of  biceps. 


Radial  (musculospiral) 

nerve,  superficial  and 

deep  branches 


Stump  of  extensor  and 
supinator  muscles 


Radial  artery 

Internal  (antibrachil 
medialis)  cutaneous 
nerve 

Median  nerve 
Ulnar  artery 

Ulnar  nerve 

Stump  of  flexor  muscles 


Fig.  317. — Amputation  at  the  elbow- joint. 

requires  ample  flaps  to  be  made  or  difficulty  will  be  encountered  in  properly  covering 
the  end  of  the  humerus.  The  irregularity  of  the  line  of  the  joint  makes  disarticula- 
tion somewhat  difficult  (Fig.  317).    • 

A  long  anterior  flap  with  or  without  a  short  posterior  one  is  usually  advised. 
On  account  of  the  tendency  to  retraction  the  ends  of  the  incision  are  not  carried  up 
to  the  condyles  but  are  kept  at  least  2.5  cm.  (i  in.)  below  them. 

If  the  flap  is  cut  by  transfixion  the  line  of  the  articulation  must  be  borne  in  mind. 
Inasmuch  as  the  trochlear  surface  projects  farther  down  than  the  capitellum  it  is 
customary  to  incline  the  knife  downward  and  inward.  Also,  as  the  trochlear  portion 
is  thicker,  wider,  and  projects  farther  than  the  capitellum,  the  inner  side  of  the  flap  is 
made  longer  than  the  outer. 

The  skin  on  the  anterior  surface  is  loose  and  retracts  freely  as  soon  as  cut  ;  hence 
the  muscles  are  often  cut  by  transfixion.  The  skin  on  the  posterior  surface  is  not  so 
loose  and  does  not  exhibit  the  same  tendency  to  retraction.  After  the  anterior 
muscles  have  been  raised  and  the  short  posterior  skin  flap  turned  back  the  joint  is  to 


THE  FOREARM.  303 

be  opened.  The  line  of  the  joint  runs  from  i.  25  cm.  below  the  lateral  (ext.  )  condyle  to 
2.5  cm.  below  the  medial  (int.)  condyle  and  is  most  readily  recognized  on  the  outer 
side,  hence  the  division  of  the  ligaments  is  to  be  made  from  the  outer  toward  the 
inner  side.  The  point  at  which  to  enter  the  knife  is  to  be  found  by  first  feeling  the 
head  of  the  radius  in  the  pit  below  the  lateral  (external)  condyle  posteriorly  and  then 
by  pressure  just  above  the  head  recognizing  the  groove  between  the  upper  edge  of 
the  head  and  capitellum.  The  knife  passes  directly  traversely  along  between  the 
head  of  the  radius  and  capitellum,  then  across  the  inner  portion  of  the  trochlea  and  is 
then  directed  downward  and  inward  around  the  projecting  inner  portion  of  the 
trochlea.  Division  of  the  internal  lateral  ligament  allows  the  forearm  to  be  bent  back 
and  the  triceps  attachment  becomes  exposed  and  can  be  di\'ided  from  the  front.  The 
appearance  of  the  stump  will  depend  on  the  manner  in  which  the  flaps  have  been  cut. 

On  each  side  will  be  the  muscular  masses  from  the  internal  and  external  con- 
dyles. Between  them  will  be  the  tendons  of  the  biceps  and  brachialis  anticus.  The 
median  and  ulnar  nerves  are  to  be  found,  the  former  to  the  inner  side  of  the  biceps 
tendon  and  the  latter  behind  the  medial  (internal)  condyle.  They  are  to  be  short- 
ened. The  radial  (musculospiral)  has  already  divided  into  its  superficial  (radial)  and 
deep  (posterior  interosseous)  branches. 

The  ulnar  and  radial  arteries  will  probably  be  found  divided  well  anterior  on  the 
face  of  the  stump.  Some  bleeding  may  be  present  from  the  terminal  branches  of  the 
profunda  in  front  of  the  lateral  condyle,  from  the  superior  ulnar  collateral  (inferior 
profunda)  behind  the  medial  condyle,  or  from  the  interosseous  or  recurrent  branches. 
It  is  usually  not  necessary  to  apply  ligatures  to  the  larger  superficial  veins. 

THE  FOREARM. 

The  forearm  is  intimately  associated  with  the  functions'  of  the  hand.  It  serves 
as  a  sort  of  pedestal  or  support,  enabling  the  hand  to  be  carried  away  from  the  body, 
and,  by  possessing  certain  movements  of  its  own, — those  of  pronation  and  supination, 
— it  increases  greatly  the  range  and  character  of  the  movements  which  the  hand 
is  capable  of  executing.  The  hand  is  the  essential  part  of  the  upper  extremity  and 
the  forearm  is  subsidiary.  Hence  we  find  that,  like  the  neck,  the  forearm  possesses 
nerves  and  blood-\-essels  much  larger  than  its  own  proper  functions  would  require  and 
which  are  destined  for  the  more  important  parts  beyond.  It  is  composed  of  two 
bones,  the  radius  and  the  ulna,  which  act  as  the  bony  support  of  the  part,  of  a  few 
muscles  which  move  these  bones  and  many  more  which  move  the  hand  and  fingers 
beyond,  and  of  certain  nerves  and  blood-vessels  that  not  only  supply  it  but  also  the 
parts  beyond. 

BONES   OF  THE   FOREARM. 

The  forearm  contains  two  bones,  instead  of  one  as  in  the  arm.  One  of  these 
bones,  the  ulna,  is  directly  continuous  with  the  humerus;  the  other,  the  radius,  is 
continuous  with  the  hand.  In  other  words,  the  ulna  is  associated  with  the  move- 
ments of  the  arm,  and  the  radius  with  those  of  the  hand.  The  large  end  of  the  ulna 
articulates  with  the  humerus  and  its  small  end  is  at  the  wrist,  while  the  large  end  of 
the  radius  is  articulated  with  the  hand  and  its  small  end  with  the  humerus. 

The  ulna  is  the  bone  which  acts  mainly  as  a  support.  It  articulates  with  the 
humerus  by  a  pure  hinge-joint;  hence  its  only  motion  is  one  of  extension  and  flexion. 
It  is  the  fixed  bone  and  does  not  take  part  in  the  movements  of  pronation  and  supi- 
nation, but  serves  as  an  anchoring  part  for  the  attachment  of  the  muscles  which  move 
the  radius  as  well  as  the  hand.  At  its  upper  extremity  it  has  attached  to  it  the 
brachialis  antiais,  triceps,  and  anco?ieus  mzcscles,  which  flex  and  extend  it. 

At  its  upper  extremity  on  its  outer  side  is  the  lesser  sigmoid  cavity  for  the  articu- 
lation of  the  radius.  Its  lower  extremity  ends  in  a  head  tipped  with  a  styloid  process. 
The  ulna  gradually  decreases  in  size  from  above  downward  until  its  lower  fourth  is 
reached,  when  it  is  slightly  enlarged  to  end  in  the  head.  At  its  lower  end,  the  lateral 
aspect  of  the  head  of  the  ulna  rests  in  a  cavity  in  the  radius  to  allow  of  the  movements 
of  pronation  and  supination  (Fig.  318). 


304 


APPLIED   ANATOMY. 


The  radius  is  small  above  and  gradually  increases  in  size  until  its  lower  extremity 
is  reached,  where  it  is  largest.  Its  upper  portion  is  composed  mainly  of  compact 
bone  with  a  medullary  cavity;  lower  down  as  the  bone  becomes  larger  it  becomes 
more  cancellous.  Hence  it  does  not  follow  that  it  is  strongest  where  it  is  largest;  on 
the  contrary  it  is  most  often  fractured  at  its  lower  extremity.  About  two  centimetres 
below  the  head  of  the  radius  is  a  tubercle.  The  biceps  tendon  is  inserted  into  its 
posterior  portion  and  a  bursa  covers  its  anterior  part,  over  which  the  tendon  of  the 
biceps  plays.      The  radius  is  the  movable  bone  and  to  it  is  attached  the  hand. 

Stretched  across  from  one  bone  to  the  other  is  the  interosseous  membrane.  Most 
of  its  fibres  run  from  the  ulna  upward  and  outward,  so  that  the  shocks  received  on  the 


Flexor  carpi  ulnaris 

Flexor  sublimis  digitorum 
Pronator  radii  teres 


Brachialis  anticus 
Supinator  (brevis) 

Flexor  sublimis  digitorum 


Flexor  profundus  digitorum 


Pronator  quadratus 


Biceps 
Supinator  (brevis) 


Pronator  radii  teres 
Flexor  sublimis  digitorum 

Flexor  longus  pollicis 


Pronator  quadratus 
Rrachioradialis 


Fig.  318. — Anterior  view  of  radius  and  ulna  with  areas  ot  muscular  attachments. 


hand  are  transmitted  somewhat  to  the  ulna.  On  its  anterior  surface  run  the  anterior 
interosseous  arteiy  and  nerve.  About  2.5  cm.  (i  in.)  above  its  lower  end  the  artery 
pierces  the  membrane  to  go  to  the  back  of  the  wrist. 


I 


MOVEMENTS   OF   PRONATION  AND   SUPINATION. 

The  radius  revolves  on  the  ulna  about  an  axis  which  passes  through  the  centre 
of  the  head  of  the  radius  above  and  the  styloid  process  of  the  ulna  below,  which  line 
if  prolonged  would  pass  through  the  ring  finger  (Fig.  319).  In  pronation,  the  hand 
lies  with  the  palm  down  and  the  radius  is  crossed  diagonally  over  the  ulna;  the  bones 
are  close  together  (Fig.  320).     In  supination  the  hand  lies  with  the  palm  up,  the 


THE  FOREARM. 


305 


bones  lie  parallel  to  one  another  and  widely  separated  (Fig.  321).  In  the  midposi- 
tion  the  radius  lies  above  the  ulna  and  the  space  between  them  is  at  its  maximum. 
The  difference  in  this  respect  between  midpronation  and  complete  supination  is 
slight.  The  head  of  the  radius  rotates  in  the  orbicular  ligament,  the  lower  end  of 
the  radius  revolves  around  the  head  of  the  ulna  and  rests  on  the  interarticular  trian- 
gular fibrocartilage.  The  range  of  movement  is  from  140  degrees  to  160  degrees. 
The  radius  is  pronated  by  the  pronator  teres  and  pronator  quadratus  muscles.  It 
is  supinated  by  the  brachioradialis,  supinator  (brevis),  and  biceps  muscles.  Some 
of  the  other  muscles  also  aid  slightly  in  these  movements,  especially  the  flexor  carpi 
radialis  in  pronation.  In  fractures  the  preservation  of  the  interosseous  space  is 
essential  for  the  proper  performance  of  pronation  and  supination;  hence  anything 


/  ^ 


Fig.  319. — The  axis  of  rotation 
in  pronation  and  supination. 


Fig.  320. — Position  of  the  bones 
of  the  forearm  when  the  hand  is  in 
the  position  of  pronation. 


Fig.  321. — Position  of  the 
bones  of  the  forearm  when  the  hand 
is  in  the  position  of  supination. 


which  tends  to  encroach  on  it,  as  displacement  of  the  fragments  or  their  position  as 
influenced  by  the  position  of  the  hand,  is  to  be  guarded  against. 

The  muscles  of  supination  are  much  stronger  than  those  of  pronation;  for  this  rea- 
son instruments  intended  to  be  used  in  a  rotary  manner  turn  from  the  inside  toward 
the  outside;  that  is,  in  the  direction  of  supination.     The  screw-driver  is  an  example. 


MUSCLES   OF   THE   FOREARM. 

The  movements  of  the  hand  and  fingers  are  so  intricate  and  complex  as  to 
necessitate  a  large  number  of  muscles  for  their  performance.  It  is  probably  easiest 
in  order  to  understand  the  construction  of  the  forearm  to  study  these  muscles  in 
reference  to  their  functions. 

The  muscles  which  occupy  the  forearm  form  three  groups,  which  have  separate 
functions:  (i)  to  flex  and  extend  the  fingers;  (2)  to  flex  and  extend  the  wrist;  (3) 
to  pronate  and  supinate  the  hand. 


3o( 


APPLIED    ANATOMY. 


I.  THE  FLEXORS  AND   EXTENSORS   OF  THE  FINGERS. 

The  fingers  are  moved  by  two  sets  of  muscles,  a  long  set  arising  from  the  fore- 
arm and  a  short  set  which  is  confined  to  the  hand.  At  present  we  are  concerned 
only  with  the  long  extensors  and  flexors  which  are  found  in  the  forearm. 


Brachialis  anticus 
Biceps 


Brachioradialis  (supinator  ]ongus) 


Flexor  longus  poUicis 


Pronator  quadratus. 


Pronator  radii  teres 

-Flexor  carpi  radialis 
-Palmaris  longus 

Flexor  sublimis  diRitorum 
Flexor  carpi  ulnaris 


Fig.  322. — Superficial  view  of  the  anterior  muscles  of  the  forearm. 

The  Flexors  of  the  Fingers. 

The  flexors  of  the  fingers  consist  of  three  separate  groups  of  muscles:  (i)  the 
Jlexor  profundus  digitoriim  and  flexor  longus  pollicis,  which  insert  into  the  distal 
phalanges;  (2)  the  flexor  sublimis  digitorum ;  (3)  the  palmaris  longus  which, 
spreading  out  into  the  palmar  fascia,  is  attached  to  the  heads  of  the  metacarpal 


THE   FOREARM. 


307 


bones  and  blends  with  the  capsules  of  the  metacarpophalangeal  joints.      It  is  an 
additional  perforated  flexor  muscle_(Fig-.  322). 

I.   The  flexor  profundus   digitorum  is  composed  of  four  slips,  one  for  each 
finger,  and  the  flexor  longus  pollicis  (Fig.  323)  is  a  fifth  slip  that  supplies  the 


Brachioradialis 

Extensor  carpi  radialis  longioj 
Extensor  carpi  radialis  brevior 


Pronator  radii  teres 

Flexor  carpi  radialis 
Palmaris  longus 
Flexor  carpi  ulnaris 


Flexor  longus  pollicis 

Pronator  quadratus 

Stump  of  flexor  carpi  radialis 

Flexor  sublimis  digitorum 


Flexor  sublimis  digitorum 


Flexor  profundus  digitorum 


Flexor  carpi  ulnaris 


Palmaris  longus  and  palm 
"ascia  turned  down 


Pig.  323. — Dissection  showing  the  muscles  of  the  forearm,  especially  the  long  flexor  muscles  of  the  fingers. 

thumb.  The  flexor  profundus  arises  from  the  anterior  surface  of  the  ulna  and  inter- 
osseous membrane  while  the  flexor  longus  pollicis  arises  from  the  anterior  surface  of 
the  radius  and  interosseous  membrane.  Their  tendons  pass  through  slits  in  the 
flexor  sublimis  digitorum  opposite  the  proximal  phalanges  to  insert  into  the  bases  of 
the  distal  phalanges. 


3o8  ^^^^^^        APPLIED    ANATOMY.  S 

2.  The  flexor  sublimis  digitorum  arises  from  the  medial  (internal)  condyle  of 
the  humerus,  the  coronoid  process,  the  intermuscular  septa,  and  the  oblique  line  of 
the  radius  and  divides  into  four  tendons  which  split  in  front  of  the  proximal  pha- 
langes to  allow  the  profundus  to  pass  through  and  then  unite  again  and  insert  into 
the  sides  of  the  middle  phalanges.  There  are  only  four  instead  of  five  slips,  because 
the  thumb  has  no  middle  phalanx  but  only  proximal  and  distal  ones  (Fig.  323). 

3.  The  palmaris  longus  arises  from  the  medial  (internal)  condyle  of  the 
humerus  and  intermuscular  septa  and  inserts  into  the  palmar  fascia,  which  is  attached 
to  the  base  of  the  proximal  phalanges,  to  the  heads  of  the  metacarpal  bones,  and 
blends  with  the  capsules  of  the  metacarpophalangeal  joints.  It  is  thus  seen  to  be  a 
perforated  muscle  exactly  like  the  flexor  sublimis,  which  it  also  resembles  in  func- 
tion; its  attachment  is  not  so  far  forward.  Traction  on  it  tends  to  flex  the  proximal 
phalanx. 

The  Extensors  of  the  Fingers. 

The  extensors  of  the  thumb  and  fingers  arise  from  the  lateral  (external)  condyle 
and  posterior  surface  of  the  ulna,  radius,  interosseous  membrane,  and  intermuscular 
septa. 

Three  separate  slips  forming  the  extensor  longus  pollicis,  extensor  brevis 
pollicis,  and  extensor  ossis  metacarpi  pollicis  go  to  the  thumb.  The  longus 
inserts  into  the  distal  phalanx,  the  brevis  into  the  proximal,  and  the  ossis  into  the 
metacarpal  bone  of  the  thumb. 

The  extensor  communis  digitorum  divides  into  four  slips,  one  for  each 
finger.  The  slip  to  the  index  is  reinforced  by  an  additional  one  called  the  exten- 
sor indicis  proprius  muscle.  The  slip  to  the  little  finger  is  reinforced  by  the 
extensor  minimi  digiti  (ext.  digiti  quinti  proprius)  muscle.  They  divide 
on  the  dorsum  of  the  proximal  phlanges  into  three  parts,  the  middle  one  inserts  into 
the  base  of  the  middle  phalanx,  while  the  two  lateral  slips  insert  into  the  base  of  the 
distal  phalanx. 

2.  THE  FLEXORS  AND   EXTENSORS  OF  THE  WRIST. 

The  muscles  which  flex  and  extend  the  fingers  of  course  also  move  the  hand 
as  a  whole,  but  in  addition  to  these  muscles  there  are  five  others, — two  flexor 
muscles  and  three  extensor  muscles, — which  are  inserted  into  the  bones  of  the  meta- 
carpus and  not  into  the  phalanges.  When  these  muscles  contract  they  tend  to 
move  the  whole  hand  and  not  the  fingers  alone.  They  are  the  flexor  carpi  radialis, 
flexor  carpi  ubiaris,  extensor  carpi  radialis  longior,  extensor  carpi  radialis  brevior, 
and  extensor  carpi  ulnaris.  The  palmaris  longus  has  already  been  described  as  a 
flexor  of  the  fingers. 

Flexors  of   the  Wrist. 

Flexor  Carpi  Radialis.  —  The  two  flexors  of  the  wrist,  the  flexor  carpi 
radialis  and  the  flexor  carpi  ulnaris,  are  both  superficial  muscles  lying  directly 
beneath  the  skin.  The  flexor  carpi  radialis  arises  from  the  medial  (internal) 
condyle  of  the  humerus  and  intermuscular  septa  and  lies  between  the  pronator 
radii  teres  externally  and  the  palmaris  longus  internally.  It  runs  obliquely  across 
the  forearm,  striking  the  wrist  at  about  the  junction  of  the  middle  and  outer  thirds. 
It  lies  next  to  and  to  the  outer  side  of  the  palmaris  longus  tendon  and  to  the  ulnar 
side  of  the  radial  artery  and  inserts  into  the  front  of  the  base  of  the  second  meta- 
carpal bone  (Fig.  324). 

Flexor  Carpi  Ulnaris. — The  flexor  carpi  ulnaris  arises  by  two  heads,  one 
from  the  common  tendon  of  the  medial  (internal)  condyle  and  the  other  from 
the  olecranon  process  and  upper  two-thirds  of  the  ulna.  The  two  heads  are 
separated  by  the  ulnar  nerve,  which  passes  down  in  the  groove  between  the  medial 
condyle  and  olecranon  process.  The  muscle  passes  straight  down  the  anterior 
and  inner  surface  of  the  ulna  to  insert  first  into  the  pisiform  bone  and  unciform 
process  and  then  to  continue  over  to  the  base  of  the  fifth  metacarpal  bone.  The 
pisiform  bone  is  a  sesamoid  bone  in  the  tendon  of  the  flexor  carpi  ulnaris  muscle. 


THE   FOREARM. 


309 


Both  die  flexor  carpi  radialis  and  the  flexor  carpi  ulnaris  flex  the  hand  at  the 
wrist.  When  the  ulnaris  alone  acts  it  tends  to  tilt  the  hand  inward;  when  the 
radialis  acts  alone  it  tends  to  incline  the  hand  outward.  Being  superficial,  these 
muscles  are  both  important  landmarks  and  guides  to  the  arteries. 


Pisiform  bone 


Fio.  324. — The  flexor  muscles  of  the  wrist.  Fig.  325. — The  extensor  muscles  of  the  wrist. 

Extensors   of   the   Wrist. 

Extensor  Carpi  Radialis  Longior. — The  extensor  carpi  radialis  longior 
arises  from  the  lower  third  of  the  external  supracondylar  ridge  and  the  lateral 
(external)  condyle  and  inserts  into  the  back  of  the  base  of  the  second  metacarpal 
bone.     When  it  contracts  it  tends  to  tilt  the  hand  toward  the  radial  side  as  well 


3IO  APPLIED    ANATOMY.  ^^^^^^^^^H 

as  to  extend  it,  and,  being  attached  to  the  humerus  above  the  line  of  the  elbow- 
joint,  it  also  aids  in  flexing  the  elbow. 

Extensor  Carpi  Radialis  Brevior. — The  extensor  carpi  radiaHs  brevior 
arises  from  the  common  tendon  of  the  lateral  condyle  and  fascia,  and,  running 
down  parallel  to  the  longior  muscle,  inserts  into  the  base  of  the  third  metacarpal 
bone.  It  is  covered  by  the  extensor  carpi  radialis  longior  muscle  and  lies  on  the 
supinator  (brevis).      It  acts  as  a  pure  extensor  of  the  wrist  (Fig.  325). 

Extensor  Carpi  Ulnaris. — The  extensor  carpi  ulnaris  arises  by  two  heads, 
one  from  the  lateral  ( external  j  condyle  and  the  other  from  the  posterior  surface  of 
the  ulna  through  the  fascia  common  to  it,  to  the  flexor  carpi  ulnaris,  and  to  the  flexor 
profundus  digitorum.  It  inserts  into  the  base  of  the  fifth  metacarpal  bone.  It  extends 
the  wrist  and  tilts  the  hand  toward  the  ulnar  side. 

3.  PRONATORS  AND  SUPINATORS   OF  THE   HAND. 

The  movements  of  pronation  and  supination  have  already  been  described 
(page  304).  They  are  performed  by  five  muscles,  two  pronators  and  three  supin- 
ators. The  pronators  are  the  pronator  radii  teres  and  the  pronator  quadratus. 
The  supinators  are  the  brachioradialis  (^supinator  longus),  the  supinator  {brevis), 
and  the  biceps. 

Pronators  of  the  Hand. 

Pronator  Radii  Teres  {Round  Pronator). — The  pronator  radii  teres  arises 
by  two  heads,  one  from  the  medial  (internal)  condyle  and  the  other,  much  smaller, 
from  the  inner  surface  of  the  coronoid  process.  The  median  nerve  passes  between 
these  two  heads.  The  muscle  crosses  the  forearm  obliquely  and  inserts  by  a  flat 
tendon  into  the  middle  of  the  outer  surface  of  the  radius.  It  rotates  the  radius 
inward  and  tends  to  draw  it  toward  the  ulna  and  flex  it  on  the  humerus.  The 
influence  of  this  muscle  is  marked  in  displacing  the  radius  when  fractured. 

Pronator  Quadratus  {Square  Pronator). — The  pronator  quadratus  arises 
from  the  volar  (palmar)  surface  of  the  lower  fourth  of  the  ulna  and  inserts  into  the 
lateral  and  anterior  surface  of  the  radius.  By  its  contraction  it  rotates  the  radius 
toward  the  ulna  and  in  cases  of  fracture  tends  to  draw  the  bones  together  and  thus 
endanger  the  integrity  of  the  interosseous  space  (Fig.  326). 

Supinators  of  the  Hand. 

Brachioradialis  {Supinator  Longus) . — The  brachioradialis  arises  from  the 
upper  two-thirds  of  the  lateral  (external)  supracondylar  ridge  of  the  humerus  and 
inserts  into  the  base  of  the  styloid  process  of  the  radius.  When  the  hand  is  in  a  state 
of  pronation  contraction  of  the  brachioradialis  will  tend  to  supinate  it.  It  also  acts 
as  a  flexor  of  the  elbow,  as  has  already  been  pointed  out.  It  is  superticiai  and  is  an 
important  guide  both  to  the  radial  (musculospiral)  nerve  and  to  the  radial  artery. 

Supinator  {Brevis). — The  supinator  arises  from  the  lateral  condyle,  the 
external  lateral  and  orbicular  ligaments,  and  the  triangular  surface  of  the  ulna 
below  the  lesser  sigmoid  cavity.  It  winds  around  the  posterior  and  external  sur- 
faces of  the  radius  and  inserts  into  the  upper  and  outer  portion,  covering  its  head, 
neck,  and  shaft  as  low  down  as  the  insertion  of  the  pronator  radii  teres  muscle. 
It  lies  deep  down  beneath  the  mass  of  extensor  muscles  and  supinates  the  radius. 
It  is  pierced  by  the  deep  branch  of  the  radial  (posterior  interosseous)  nerve  which 
bears  the  same  relation  to  it  as  does  the  external  popliteal  nerve  to  the  peroneus 
longus  muscle  in  the  leg. 

Biceps  Muscle. — The  biceps  muscle  has  already  been  described.  Arising 
by  its  long  head  from  the  upper  edge  of  the  glenoid  cavity  and  by  its  short  head 
from  the  coracoid  process  it  inserts  into  the  posterior  portion  of  the  tubercle  of 
the  radius.  While  its  main  function  is  that  of  flexion  of  the  elbow,  still,  from  the 
manner  in  which  it  winds  around  the  tubercle  of  the  radius,  it  acts  as  a  powerful 
supinator  when  the  hand  is  prone  and  it  is  a  disturbing  factor  in  the  displacements 
which  occur  in  fractures  of  the  bones  of  the  forearm. 


THE   FOREARM. 


3" 


Pronator  radii  teres 


—    Biceps 


Brachioradialis 
(supinator  longus) 


Supinator  (brevis) 


Pronator  quadratus  ■ 


^^^ 


Fig.  326. — The  pronator  and  supinator  muscles  of  the  left  forearm. 


312 


APPLIED  ANATOMY. 


SURFACE  ANATOMY  OF  THE  FOREARM. 

The  forearm  has  the  shape  of  a  somewhat  flattened  cone,  being  large  above  and 
small  below.  This  is  because  the  bellies  of  the  muscles  lie  above  and  their  tendons 
below.  Most  of  the  muscles  of  the  forearm  go  to  the  hand  and  fingers.  The 
prehensile  functions  of  the  hand  require  a  strong  grasp;  hence  it  is  that  we  find 
the  flexor  muscles  on  the  anterior  surface  of  the  forearm  much  larger  and  more 
powerful  than  the  extensors  posteriorly,  and  the  bones  of  the  forearm,  the  radius  and 
ulna,  nearer  the  surface  posteriorly. 

Anterior  Surface. — Anteriorly  nothing  is  to  be  felt  except  muscles  and 
tendons.     The  extent  to  which  these  can  be  outlined  depends  on  the  absence  of 


Supinators  and  extensors 


Tendon  of  flexor  carpi  radialis 


Pronator  and  flexors 


Tendon  of  palmaris  longus 
Transverse  furrows 


Fio.  327. — Surface  anatomy  of  the  forearm. 


subcutaneous  fat  and  the  degree  of  development  and  contraction  of  the  individual 
muscles.  The  skin  of  the  forearm  is  loose  and  thin.  Through  it  can  be  seen 
anteriorly,  the  median  vein  going  up  the  middle  and  the  radial  vein  winding  around 
the  back  of  the  wrist  and  crossing  the  outer  edge  of  the  radius  about  its  middle. 
On  the  inner  side  near  the  elbow  the  anterior  and  posterior  ulnar  veins  are  visible 
passing  posteriorly. 

Sometimes  there  is  a  slight  depression  on  the  inner  side  below  the  medial 
(internal)  condyle  which  is  caused  by  the  bicipital  fascia  Ijolding  the  muscle  down. 
The  biceps  tendon  can  be  felt  at  the  bend  of  the  elbow,  and  immediately  below 
it  for  the  distance  of  5  cm.  (2  in. )  can  be  felt  a  hollow,  the  antecubital  fossa.  The 
mass  of   muscles  between   it  and  the  ulna  on  the  inside  and  posteriorly  are  the 


I 


THE   FOREARM. 


313 


flexors  and  pronator  radii  teres;  the  mass  of  muscles  on  the  outer  side  between  it 
and  the  radius  posteriorly  are  the  extensors,  supinator  (brevis),  and  brachioradialis. 
The  inner  edge  of  the  brachioradialis  is  indicated  by  a  line  drawn  from  the  outer 
side  of  the  biceps  tendon  to  the  outer  surface  of  the  styloid  process  of  the  radius. 
A  line  from  the  medial  (internal)  condyle  running  obliquely  across  the  forearm  to 
the  middle  of  the  radius  indicates  the  pronator  radii  teres  muscle.  A  line  from  the 
medial  condyle  to  the  middle  of  the  wrist  indicates  the  palmaris  longus  muscle; 
it  is  sometimes  absent.  Another  line  from  the  same  point  above  to  a  centimetre 
to  the  radial  side  of  the  palmaris  longus  tendon  at  the  wrist  indicates  the  flexor 


Triceps  tendon 


Internal  condyle 
Olecranon  process 


Ulna 


Extensor  carpi  ulnaris 


Styloid  process  of  ulna 


Brachialis  anticus 
External  bicipital  furrow 

Depression,  head  of  radius 

External  condyle 

Brachioradialis  and  extensor 
carpi  radialis  longior 
Anconeus 


Extensor  communis  digitorum 


Extensors  of  the  thumb 

Styloid  process  of  radius 
Extensor  longus  poUicis 


Fig.  328. — Surf  ace  anatomy  of  the  back  of  the  forearm. 

carpi  radialis  muscle.  The  tendons  of  both  these  muscles  can  readily  be  seen.  A 
hne  drawn  from  the  medial  (internal)  condyle  to  the  pisiform  bone  at  the  wrist 
indicates  the  anterior  edge  of  the  flexor  carpi  ulnaris  muscle. 

Having  located  the  superficial  muscles  the  arteries  and  nerves  can  be  traced. 
The  brachial  artery  bifurcates  about  a  finger's  breadth  below  the  bend  of  the  elbow. 
A  line  drawn  from  the  inner  edge  of  the  biceps  tendon,  or  a  point  midway  between 
the  two  condyles,  to  the  anterior  surface  of  the  styloid  process  of  the  radius  indi- 
cates the  course  of  the  radial  artery.  In  the  upper  half  of  the  forearm  it  is  over- 
lapped by  the  edge  of  the  brachioradialis.  In  the  lower  half  it  is  uncovered  by 
muscle  and  lies  in  the  groove  formed  by  the  brachioradialis  on  the  outer  side  and  the 
flexor  carpi  radialis  on  the  inner.  The  ulnar  artery  describes  a  marked  curve  toward 
the  ulnar  side  until  it  reaches  the  middle  of  the  forearm,  when  it  passes  down  in  a 
straight  line  from  the  medial  (internal)  condyle  to  the  radial  side  of  the  pisiform  bone. 


^^™^^^^^^^       APPLIED   ANATOMY.  -^^^^^^^m 

The  median  nerve  runs  down  the  middle  of  the  forearm,  lying  beneath  the 
groove  separating  the  palmaris  longus  and  flexor  carpi  radialis  tendons.  The  ulnar 
nerve  runs  from  the  groove  between  the  medial  (internal)  condyle  and  olecranon 
process  above  to  the  radial  or  outer  side  of  the  pisiform  bone  below.  It  lies  to  the 
ulnar  side  of  the  ulnar  artery  in  the  lower  half  of  the  forearm.  The  rounded  mus- 
cular mass  between  the  edge  of  the  flexor  carpi  ulnaris  and  the  palmaris  longus  is 
formed  by  the  flexor  sublimis  digitorum  muscle  (Fig.  327). 

Posterior  Surface. — The  posterior  surface  differs  from  the  anterior  in  the 
bones  being  more  conspicuous — they  are  subcutaneous.  Of  the  two  the  ulna  is  the 
more  evident.  At  the  elbow  the  olecranon  and  the  capitellum  to  its  outer  side  are 
well  marked  and  some  distance  inwardly  is  the  medial  (internal)  condyle.  By  pal- 
pation the  ulna  can  be  traced  down  the  forearm  almost  subcutaneous,  running  from 
the  olecranon  process,  in  a  gentle  curve  toward  the  median  line,  down  to  its  styloid 
process  at  the  back  of  the  wrist.  It  is  covered  only  by  the  skin  and  superficial  and 
deep  fascias.  About  3  cm.  (i}(  in.)  to  the  outer  side  of  the  olecranon  can  be  felt 
the  lateral  (external)  condyle  and  capitellum.  If  the  elbow  is  extended  a  dimple 
is  seen  just  below  the  capitellum  ;  it  marks  the  position  of  the  head  of  the  radius, 
and  by  pressure  the  groove  separating  the  head  from  the  capitellum  can  be  felt. 

By  placing  the  thumb  of  one  hand  in  the  dimple  on  the  head  of  the  radius,  and 
rotating  the  hand  of  the  patient  with  the  other,  one  can  feel  the  bone  rotate  and  thus 
be  assured  that  the  radius  is  intact.  Whenever  fracture  of  the  radius  is  suspected 
this  is  the  procedure  resorted  to  in  order  to  determine  whether  or  not  it  is  broken. 

The  radius  can  be  followed  only  for  an  inch  or  so  below  the  dimple,  when  it 
disappears  beneath  the  muscles  to  again  become  subcutaneous  on  the  outer  side  of 
the  forearm,  about  its  middle,  from  thence  it  can  be  followed  more  or  less  distinctly 
down  to  the  styloid  process  on  the  outer  side  of  the  wrist. 

The  ulna  being  subcutaneous,  fracture  can  be  determined  by  palpating  it  from 
the  olecranon  down  the  back  of  the  forearm  to  the  styloid  process. 

The  line  of  the  ulna  is  usually  marked  by  the  presence  of  a  groove.  To  the 
ulnar  side  of  the  groove  lie  the  flexor  carpi  ulnaris  and  the  other  flexors;  to  the 
radial  side  He  the  extensor  carpi  ulnaris  and  the  other  extensors  (Fig.  328). 

From  the  dimple  marking  the  head  of  the  radius  a  groove  in  the  muscles  can  be 
felt  which  runs  to  the  middle  of  the  outer  surface  of  the  radius.  Anterior  or  to  the 
palmar  side  of  this  groove  lie  the  brachioradialis  and  extensor  carpi  radialis  longior 
with  the  supinator  (brevis)  beneath.  The  muscles  posterior  or  between  the  groove 
and  the  ulna  are  the  extensor  carpi  radialis  brevior,  extensor  communis  digitorum, 
and  extensor  carpi  ulnaris.  Passing  over  the  lower  third  of  the  outer  side  of  the 
radius  are  the  tendons  of  the  extensor  ossis  metacarpi  poUicis  and  extensor  brevis 
poUicis  muscles.  As  they  are  here  subcutaneous,  this  is  the  point  at  which  creaking 
can  be  felt  when  they  are  affected  with  tenosynovitis. 

ARTERIES   OF   THE   FOREARM. 

A  knowledge  of  the  arteries  of  the  forearm  is  necessary  on  account  of  the  trouble- 
some hemorrhage  which  they  cause  when  wounded. 

At  the  bend  of  the  elbow,  a  finger's  breadth  below  the  crease  and  opposite  the 
neck  of  the  radius,  the  brachial  artery  divides  into  the  radial  and  iihiar  arteries. 
These  are  continued  through  the  forearm  to  enter  the  hand,  the  ulnar  anteriorly  over 
the  annular  ligament  and  the  radial  posteriorly  through  the  "  anatomical  snuff-box." 

The  ulnar  artery  is  larger  than  the  radial  and  in  its  upper  half  it  describes  a 
curve  with  its  convexity  toward  the  ulnar  side  passing  beneath  the  pronator  radii 
teres  and  superficial  flexor  muscles  arising  from  the  medial  (internal)  condyle.  It  is 
accompanied  by  venae  comites  but  not  by  any  nerve  in  this  portion  of  its  course. 
Just  above  the  middle  of  the  forearm  the  ulnar  nerve  joins  the  artery,  lying  to  its 
ulnar  side,  and  accompanies  it  down  into  the  hand.  In  the  lower  half  of  its  course 
the  ulnar  artery  lies  to  the  radial  side  of  the  flexor  carpi  ulnaris  muscle,  being  slightly 
overlapped  by  it.  The  flexor  sublimis  on  the  radial  side  also  tends  to  overlap  it. 
The  covering  of  the  artery,  partially  at  least,  by  these  muscles,  together  with  the 
thickness  of  the  deep  fascia  and  the  lack  of  a  proper  bony  support  beneath,  cause  the 


THE   FOREARM. 


315 


pulse  from  the  ulnar  artery  to  be  less  distinctly  felt  than  that  from  the  radial.  When 
the  artery  passes  beneath  the  pronator  radii  teres  muscle  it  is  crossed  by  the  median 
nerve,  which  lies  superficial  to  the  artery,  and  is  separated  from  it  by  the  deep  head 
of  the  muscle.  The  branches  of  the  ulnar  artery  in  the  forearm  are  the  anterior  and 
posterior  ulnar  recurrents,  the  common  interosseous,  muscular,  nutrient,  and  anterior 
and  posterior  ulnar  carpal  branches  (Fig.  329). 

The  anterior  ulnar  recurrent  runs  upward  between  the  edges  of  the  pronator 
radii  teres  and  brachialis  anticus. 


Radial  recurrent 


Radial  artery 
Interosseous  recurrent 
Posterior  interosseous 


Brachioradialis  muscle 


Flexor  carpi  radialis  muscle 


Median  nerve 
Superficial  volar 


Brachial  arterv 


Anterior  ulnar  recurrent 
Posterior  ulnar  recurrent 
Ulnar  artery 
Common  interosseous 

.\nterior  interosseous 


Flexor  carpi  ulnaris  muscle 


Ulnar  nerve 

Palmaris  longus  tendon 

Anterior  carpal  branch  of  the  ulnar 


Fig.  329. — Arteries  of  the  forearm. 

The  posterior  ulnar  rectirrent  passes  upward  with  the  ulnar  nerve  behind  the 
medial  (internal)  condyle. 

The  common  interosseozis  artery  comes  off  from  the  ulnar  about  2  to  3  cm.  from  its 
origin  and  divides  into  the  volar  (anterior)  and  dorsal  (posterior)  interosseous  arteries. 
The  anterior  gives  a  branch  to  the  median  nerve — the  comes  nervi  median! — a  nutrient 
branch  to  the  radius,  and,  on  reaching  the  upper  edge  of  the  pronator  quadratus,  sends 
a  posterior  terminal  branch  through  the  membrane  and  an  anterior  terminal  branch  into 
the  muscle.  The  posterior  interosseous  passes  beneath  the  oblique  ligament  to  the  back 
of  the  forearm  and  gives  of?  the  interosseous  recurrent,  which  runs  up  between  the  lateral 
(external)  condyle  and  the  olecranon  and  then  gives  branches  to  the  various  muscles. 


3i6  ^^^^^        APPLIED    ANATOMY.  ^^^^^^^^ 

The  radial  artery,  though  smaller  than  the  ulnar,  seems  to  be  a  direct  con- 
tinuation of  the  brachial  because  it  proceeds  in  the  same  general  direction  while  the 
ulnar  branches  off  to  one  side.  It  is  divided  into  three  parts  according  to  the 
region  it  traverses,  viz.,  the  forearm,  the  wrist,  and  the  hand.  It  describes  a  slightly 
outward  curved  line  from  a  finger's  breadth  below  the  middle  of  the  crease  of  the 
elbow  to  a  point  on  the  front  of  the  radius  at  the  wrist,  i  cm.  (|-  in.)  inside  of  its 
styloid  process.  It  is  superficial  in  nearly  its  entire  extent,  being  overlapped  only 
by  the  edge  of  the  brachioradialis  (supinator  longus)  in  its  upper  third.  This 
muscle  lies  to  its  outer  side  all  the  way  down  to  the  styloid  process.  In  the  middle 
third  the  cutaneous  branch  of  the  radial  nerve  lies  close  to  the  outer  side  of  the 
artery,  but  in  the  lower  third  the  nerve  leaves  it  to  become  subcutaneous,  passing 
more  toward  the  dorsum. 

To  the  inner  side  of  the  artery  is  the  pronator  radii  teres  muscle  in  its  upper 
third  and  the  flexor  carpi  radialis  for  the  rest  of  its  course.  At  the  wrist  it  rests  on 
the  anterior  surface  of  the  radius,  a  centimetre  to  the  inner  side  of  its  styloid  process. 
By  compressing  the  vessel  against  the  bone  its  pulsations  can  be  readily  felt,  and  here 
is  where  the  finger  is  applied  in  taking  the  pulse. 

The  branches  of  the  radial  artery  are  the  recurrent,  muscular,  anterior  radial 
carpal  and  superficial  volar. 

The  radial  recurrent  arises  from  the  radial  soon  after  its  origin  and  follows  the 
radial  nerve,  in  the  groove  between  the  brachialis  anticus  and  brachioradialis. 

The  anterior  carpal  is  a  small  branch  which  joins  with  the  corresponding  branch 
of  the  ulnar  and  anterior  terminal  branch  of  the  anterior  interosseous  to  form  a  so- 
called  anterior  carpal  arch  which  anastomoses  with  branches  of  the  deep  palmar  arch 
to  supply  the  bones  and  joints  of  the  carpus. 

The  superficial  volar  leaves  the  radial  artery  just  before  it  crosses  the  external 
lateral  ligament.  It  pierces  the  muscles  of  the  thumb  to  anastomose  with  a  superficial 
branch  of  the  superficial  palmar  arch.  Sometimes  this  artery  is  so  large  that  it  can  be 
seen  pulsating  as  it  passes  over  the  thenar  eminence  from  the  wrist  downward. 

Ligation  of  the  Ulnar  Artery  in  the  Forearm. — The  ulnar  artery  between 
the  elbow  and  wrist  is  so  large  that  when  wounded  it  may  require  ligation  in  any 
part  of  its  course.  On  account  of  the  artery  being  deep  beneath  the  flexor  muscles 
in  the  upper  part  of  the  forearm,  the  middle  and  lower  portions  are  to  be  preferred 
for  ligation  (Fig.  330). 

Ligation  in  the  Upper  Third. — This  is  done  only  for  wounds.  The  superficial 
incision  may  be  made  in  a  line  from  the  medial  (internal)  condyle  to  the  middle 
of  the  outer  border  of  the  radius.  The  fibres  of  the  pronator  radii  teres  are  to 
be  parted,  not  cut,  and  the  artery  searched  for  crossing  the  wound  almost  at  right 
angles,  on  a  line  from  the  bifurcation  of  the  brachial  artery  to  the  middle  of  the 
inner  border  of  the  ulna.  The  artery  is  to  be  found  lying  between  the  superficial 
flexor  muscles  arising  from  the  medial  condyle  and  the  deep  muscles  arising 
from  the  two  bones  and  the  interosseous  membrane.  It  lies  beneath  the  ulnar 
head  of  the  pronator  radii  teres,  which  separates  it  from  the  median  nerve,  which 
is  superficial  to  it  and  nearer  the  median  line. 

Ligation  in  the  Middle   Third. — The   ulnar  artery  reaches   the   inner   edge  of 
the  ulna  at  its  middle  and  from  thence  downward  runs  in  a  straight  line  from  the  . 
medial  (internal)  condyle  to  the  radial  side  of  the  pisiform  bone.      It  lies  directly 
under  the  deep  fascia  and  along  the  radial  or  outer  edge  of  the  flexor  carpi  ulnaris 
muscle,  which  can  be  made  tense  by  extending  and  abducting  the  hand. 

In  the  upper  part  of  its  middle  third  the  artery  lies  under  the  edge  of  the  flexor 
sublimis  digitorum  and  the  ulnar  nerve  lies  a  short  distance  to  its  ulnar  side.  In  the 
lower  part  of  the  middle  third  the  artery  and  nerve  lie  close  together,  the  nerve 
being  next  to  the  tendon  of  the  flexor  carpi  ulnaris.  The  tendon  to  the  radial  side 
of  the  artery  is  one  of  the  slips  of  the  flexor  sublimis  digitorum. 

If  difficulty  is  found  in  recognizing  the  edge  of  the  flexor  carpi  ulnaris  after  the 
skin  incision  has  been  made  the  hand  should  be  extended  and  abducted:  this  may 
make  the  muscle  tense.  Sometimes  the  intermuscular  space  is  marked  by  a  white 
or  yellow  (fatty)  line  or  by  some  small  blood-vessels  coming  to  the  surface  at  this 
point.     The  edge  of  the  flexor  carpi  ulnaris  is  more  likely  to  be  to  the  radial  than  to 


THE   FOREARM. 


317 


the  ulnar  side  of  the  skin  incision.      The  needle  is  to  be  passed  between  the  nerve 
and  artery  from  the  ulnar  toward  the  radial  side. 

Ligation  hi  the  Lower  Third. — The  relations  of  the  artery  are  practically  the 
same  as  in  the  lower  part  of  the  middle  third.  In  the  superficial  fascia  one  of  the 
branches  of  the  anterior  ulnar  vein  may  be  encountered.  It  should  not  be  mistaken 
for  the  artery.  The  artery  lies  beneath  the  deep  fascia  ;  the  edge  of  the  flexor  carpi 
ulnaris  muscle  should  be  clearly  recognized.  The  deep  fascia  is  apt  to  have  two 
layers,  one  passing  from  the  edge  of  the  flexor  carpi  ulnaris  over  the  flexor  sublimis 
while  the  other,  more  superficial,  goes  more  to  the  anterior  surface  of  the  annular 


Radial  nerve 

Radial  artery 

Brachioradialis  muscle 


Radial  artery 


Flexor  carpi  ulnaris  muscle 
Ulnar  nerve 
Ulnar  artery 


Flexor  carpi  ulnaris  tendon 
Ulnar  nerve 
Ulnar  artery 


Fig.   330. — Ligation  of  the  radial  and  ulnar  arteries. 

ligament.      Care  is  to  be  taken  not  to  work  laterally  between  these  layers  but  to 
isolate  and  recognize  the  edge  of  the  flexor  carpi  ulnaris  muscle. 

The  ner\e  lies  between  the  tendon  and  artery,  which  latter  has  venae  comites. 
The  needle  is  to  be  passed  from  the  ulnar  toward  the  radial  side. 


NERVES  OF  THE  FOREARM. 

Injuries  of  the  large  nerves  of  the  forearm  are  followed  by  much  disability. 
When  the.se  nerves  are  divided  in  wounds  it  is  desirable  to  unite  the  ends  imme- 
diately. The  reunion  of  nerve-trunks  which  have  been  divided  some  time  previously 
is  also  occasionally  necessary. 


3i8 


APPLIED    ANATOMY. 


These  operations  demand  on  the  part  of  the  surgeon  an  accurate  knowledge 
of  the  topography  of  the  part.  For  our  purpose  we  may  consider  the  nerves  of  the 
forearm  as  being  of  two  kinds — trunks  and  branches.  There  are  two  main  trunks — 
the  median  and  the  ulnar;  the  superficial  (radial),  and  deep  (interosseous)  branches 
of  the  radial  (musculospiral),  and  forearm  branches  of  the  median  and  ulnar  form 
the  second  class.  The  main  trunks  simply  traverse  the  forearm  to  be  distributed 
in  the  hand,  therefore  injury  to  them  shows  itself  by  disabilities  of  the  hand.  The 
branches  supplying  the  forearm,  if  of  sensation,  rarely  give  rise  to  any  serious  effects 
requiring  surgical  interference.     The  motor  branches  enter  the  muscles  of  the  fore- 


N.  cutaneus  antibrachii  lateralis 
(external  or  musculocutaneous) 

N.  radialis,  ramus  profundus 
(posterior  interosseous) 

N.  radialis,  ramus  superficialis 
(radial  nerve) 


Brachioradialis  muscle 


Median  nerve 


N.  cutaneus  antibrachii 
medialis  (internal  cutaneous) 


Pronator  radii  teres  muscle 


Ulnar  nerve 

Flexor  carpi  radialis  muscle 
Palmaris  longus  muscle 
Flexor  carpi  ulnaris  muscle 


i  si  form  bone 


Fig.  331. — The  nerves  of  the  forearm. 

arm  so  high  up  that  paralysis  usually  is  seen  only  when  the  nerves  are  injured  in 
the  region  of  the  elbow  or  above.  The  high  entrance  is  caused  by  the  bellies  of  the 
muscles  being  above  and  the  part  below  being  tendinous  (Fig.  331). 

The  Median  Nerve. — The  median  nerve  at  the  elbow-joint  lies  internal  to 
the  brachial  artery,  which  lies  next  and  internal  to  the  biceps  tendon.  It  lies  on  the 
brachialis  anticus  muscle  and  under  the  bicipital  fascia.  It  crosses  the  ulnar  artery 
obliquely  a  short  distance  below  its  origin.  The  artery  curves  toward  the  ulnar  side 
while  the  nerve  has  a  slight  curve  toward  the  radial  side ;  between  the  two  passes  the 
ulnar  head  of  the  pronator  radii  teres  muscle.     The  nerve  then  proceeds  downward 


THE   FOREARM.  319 

between  the  superficial  and  deep  layers  of  muscles.  It  lies  on  the  flexor  profundus 
digitorum  and  is  covered  by  the  flexor  sublimis;  about  5  cm.  above  the  annular  liga- 
ment it  becomes  more  superficial  and  lies  in  the  interval  between  the  palmaris  longus 
and  flexor  carpi  radialis  tendons  and  touching  them.  It  then  passes  under  the  annu- 
lar ligament  to  enter  the  palm  of  the  hand.  A  branch  of  the  anterior  interosseous 
artery  called  the  comes  nervi  viediani  accompanies  the  nerve  in  the  forearm. 

Branches. — The  median  nerve  gives  ofT  muscular,  volar  (anterior)  interosseous, 
an<i  palmar  cutaneous  branches,  besides  those  in  the  hand. 

The  superficial  flexor  muscles,  with  the  exception  of  the  flexor  carpi  ulnaris, 
are  supplied  by  branches  directly  from  the  main  trunk  near  the  elbow  ;  the  one 
to  the  pronator  radii  teres  usually  comes  off  above  the  elbow.  The  deep  flexor 
muscles,  with  the  exception  of  the  inner  half  of  the  flexor  profundus  digitorum,  are 
supplied  by  the  volar  Canterior)  interosseous  branch. 

The  volar  {a?iterior)  interosseous  nerve  leaves  the  main  trunk  of  the  median 
just  below  the  elbow  and  accompanies  the  volar  (anterior)  interosseous  artery, 
lying  on  the  interosseous  membrane  between  the  flexor  longus  pollicis  and  the 
flexor  profundus  digitorum.  It  supplies  the  flexor  longus  pollicis  and  radial  half 
of  the  flexor  profundus  muscles  as  well  as  the  pronator  quadratus. 

The  palmar  cntaneous  branch  is  given  off  just  above  the  annular  ligament  and 
comes  to  the  surface  between  the  palmaris  longus  and  flexor  carpi  radialis  tendons. 
It  passes  over  the  annular  ligament  to  be  distributed  to  the  thenar  eminence  and 
palm  of  the  hand. 

Wounds  of  the  Median  Nerve. — The  median  nerve  may  be  wounded  in 
any  part  of  its  course  in  the  forearm,  but  it  is  superficial  only  in  its  lower  portion  for 
about  5  cm.  above  the  wrist.  From  this  point  up  it  is  covered  by  the  flexor  sublimis, 
the  flexor  carpi  radialis  and  the  pronator  radii  teres. 

While  these  muscles  tend  to  protect  it  from  injury,  if  the  traumatism  is  exten- 
sive enough  to  divide  it  they  render  it  all  the  more  difficult  to  treat.  Accompanying 
the  nerve,  especially  in  the  middle  third  of  the  forearm,  is  the  comes  nervi  mediani 
artery,  which  may  cause  annoying  bleeding.  Careless  attempts  to  secure  the  artery 
may  injure  the  nerve.  Should  the  nerve  be  divided,  paralysis  ensues  of  all  the 
superficial  flexor  muscles  except  the  flexor  carpi  ulnaris,  and  of  the  deep  muscles, 
except  the  inner  half  of  the  flexor  profundus.  This  includes  the  pronator  radii  teres 
and  pronator  quadratus,  so  that  the  power  of  pronating  the  forearm  is  impaired 
as  well  as  the  ability  to  flex  the  hand.  The  flexor  carpi  ulnaris  and  outer  half  (that 
going  to  the  ring  and  little  fingers)  of  the  flexor  profundus  digitorum  are  the  only 
flexor  muscles  not  paralyzed. 

The  paralyzed  flexor  muscles  atrophy  and  the  size  of  the  forearm  is  much 
reduced.  There  will  also  be  impairment  of  the  functions  of  sensation  and  motion  in 
the  hand,  which  will  be  alluded  to  later. 

Operations. — ^To  find  the  nerve  in  the  upper  third  of  the  forearm  an  incision 
may  be  made  at  the  inner  side  of  the  biceps  tendon  and  brachial  artery.  The 
median  nerve  will  be  found  to  the  inner  side  of  the  artery  and  may  be  followed 
down.  When  the  pronator  radii  teres  is  reached  it  must  either  be  drawn  to  the 
ulnar  side  or  divided. 

The  fascial  expansion  cov^ering  the  flexor  sublimis  is  next  reached;  it  must  be 
slit  up  and  the  muscular  fibres  parted  to  reach  the  nerve  lying  between  it  and  the 
flexor  profundus,  with  the  volar  (anterior)  interosseous  nerve  alongside. 

To  reach  the  nerve  in  the  middle  third  of  the  forearm  the  guide  should  be  the 
palmaris  longus  tendon.  The  nerve  lies  in  a  line  joining  the  outer  edge  of  the  palma- 
ris longus  tendon  at  the  wrist  and  the  brachial  artery  at  the  inner  side  of  the  biceps 
tendon  at  the  elbow.  If  an  incision  is  made  in  the  middle  of  the  forearm  one  comes 
down  on  the  belly  of  the  flexor  carpi  radialis  muscle  and  it  is  necessary  to  part  its 
fibres  as  well  as  those  of  the  flexor  sublimis  beneath.  If  one  goes  a  little  lower  down 
and  places  the  incision  between  the  palmaris  longus  and  flexor  carpi  radialis  the  latter 
may  be  drawn  outward,  but  the  fascia  covering  the  flexor  sublimis  will  still  have  to 
be  incised.      The  comes  nervi  mediani  artery  will  be  found  accompanying  the  nerve. 

To  reach  the  nerve  in  its  lower  third  is  the  easiest  because  it  becomes  super- 
ficial about  5  centimetres  (2  in.  J  above  the  wrist.      Here  it  lies  either  beneath  the 


^i^^^^^^^^"^       APPLIED    ANATOMY.  ^^^^^^^B 

tendon  of  the  palmaris  longus  or  between  it  and  the  flexor  carpi  radialis.  The 
incision  should  be  made  between  the  muscles.  A  layer  of  deep  fascia  will  be  found 
beneath  them,  which  must  be  incised.  From  this  point  the  nerve  can  be  followed  up 
beneath  the  flexor  sublimis  or  downward  beneath  the  annular  ligament.  Care  is  to  be 
taken  not  to  disturb  the  tendons  of  the  flexor  sublimis  at  the  wrist. 

The  Ulnar  Nerve.  —  The  ulnar  nerve  passes  downward  in  the  groove  on 
the  back  of  the  medial  (internal)  condyle  and  between  the  condyle  and  olecranon 
process.  It  passes  between  the  two  heads  of  the  flexor  carpi  ulnaris  muscle  and  is 
covered  by  it,  lying  on  the  flexor  profundus  digitorum  ;  when  half  way  down  the 
forearm  it  becomes  superficial  and  lies  under  or  at  the  edge  of  the  flexor  carpi 
ulnaris  muscle  with  the  ulnar  artery  and  flexor  sublimis  muscle  to  its  outer  or  radial 
side.  The  ulnar  artery  joins  the  nerve  just  above  the  middle  of  the  forearm.  Just 
below  the  elbow  the  artery  gives  off  the  posterior  ulnar  recurrent  branch,  which 
passes  up  with  the  nerve  behind  the  medial  condyle.  From  the  middle  of  the 
forearm  to  the  wrist  the  ulnar  nerve  lies  behind  and  to  the  ulnar  side  of  the  artery. 

Branches. — It  gives  muscular  branches  in  the  upper  third  of  the  forearm  to 
the  flexor  carpi  ulnaris  and  ulnar  half  of  the  flexor  profundus  digitorum  muscles. 
It  gives  small  articular  branches  to  both  the  elbow-joint  and  wrist-joint. 

It  also  gives  off  anterior  and  posterior  cutaneous  branches.  The  anterior,  one 
or  two,  come  off  about  the  middle  of  the  forearm  ;  one  supplies  the  anterior  surface 
of  the  ulnar  side  of  the  forearm,  while  another,  called  the  palmar  aitaneous,  runs 
down  the  front  of  the  artery  to  be  distributed  to  the  palm. 

The  dorsal  or  posterior  cutaneous  branch  is  given  off  about  5  cm.  (2  in.)  above 
the  wrist  and  passes  downward  and  backward  beneath  the  tendon  of  the  flexor  carpi 
ulnaris,  across  the  interval  between  the  pisiform  bone  and  styloid  process  of  the  ulna, 
over  the  tendon  of  the  extensor  carpi  ulnaris,  and  thence  to  the  fingers. 

Wounds. — This  nerve  in  the  forearm  is  not  infrequently  wounded.  It  is 
especially  liable  to  injury  in  resecting  the  elbow-joint.  From  what  has  been  said  of 
its  course  and  branches  it  will  be  seen  that  in  order  for  paralysis  of  any  of  the 
muscles  of  the  forearm  to  be  produced  it  must  be  injured  high  up  in  its  upper  third. 
Then  the  flexor  carpi  ulnaris  and  inner  half  of  the  flexor  profundus  digitorum  will 
be  paralyzed.  If  injured  lower  down  the  only  muscular  paralysis  which  will  ensue 
is  that  of  the  short  muscles  of  the  hand  which  it  supplies. 

If  the  nerve  is  divided  above  the  middle  of  the  forearm  the  anterior  cutaneous 
nerves  will  be  involved.  If  divided  between  that  point  and  5  cm.  above  the  wrist 
the  anterior  cutaneous  escapes  but  the  dorsal  cutaneous  branch  is  paralyzed.  Below 
this  latter  point  the  dorsal  cutaneous  branch  escapes  and  the  muscular  and  sensory 
disturbances  produced  are  on  the  palmar  surface  (except  the  dorsal  interossei  muscles). 

Operations. — In  all  operations  on  the  nerve  it  should  be  remembered  that  its 
course  is  a  straight  line  from  the  medial  condyle  to  the  radial  edge  of  the  pisiform 
bone.  In  the  lower  half  of  its  course  it  lies  along  the  outer  (radial)  edge  of  the 
flexor  carpi  ulnaris  and  this  tendon  will  serve  as  a  guide  to  it.  It  is  here  covered 
only  by  skin  and  superficial  and  deep  fasciae,  though  it  may  be  overlapped  by  either 
the  artery  or  the  edge  of  the  tendon.  If  it  is  desired  to  reach  the  nerve  in  its 
upper  half  it  can  be  followed  either  from  above  downward  or  from  below  upward, 
the  fibres  of  the  flexor  carpi  ulnaris  muscle  which  cover  it  being  split  to  the  extent 
necessary  for  proper  exposure.  Below  the  middle  of  the  forearm  the  ulnar  artery 
lies  to  its  radial  side.  Near  the  elbow  the  posterior  ulnar  recurrent  artery  accom- 
panies it  upward,  but  the  nerve  is  far  removed  from  the  ulnar  artery  in  this  part  of 
its  course. 

The  Volar  Interosseous  Nerve  and  the  Superficial  and  Deep  Branches 
of  the  Radial  (Musculospiral). — In  addition  to  the  large  nerve-trunks  of  the 
median  and  ulnar  the  forearm  contains  the  volar  (anterior)  interosseous,  and  the 
deep  and  superficial  branches  of  the  radial  (musculospiral)  nerve. 

The  volar  {anterior^  interosseous  nerve  leaves  the  median  opposite  to  or  below 
the  bicipital  tubercle  of  the  radius  ;  it  lies  on  the  interosseous  membrane  to  the  ulnar 
side  of  the  accompanying  volar  interosseous  artery.  It  supplies  the  outer  half  of  the 
flexor  profundus  digitorum  and  the  flexor  longus  poUicis  muscles,  between  which  it 
lies,  and  the  pronator  quadratus  muscle.      It  is  rarely  wounded  alone. 


THE   FOREARM.  321 

The  deep  and  superficial  branches  are  the  continuation  of  the  radial  (musculo- 
spiral)  which  divides  in  the  groove  between  the  brachioradialis  (supinator  longus) 
and  brachialis  anticus  muscles  just  above  the  elbow. 

The  deep  branch  {posterior  interosseous^  is  the  larger  and  is  a  muscular  nerve  ; 
the  superficial  branch  (radial)  is  smaller  and  is  solely  sensory.  The  deep  branch 
passes  down  under  the  brachioradialis  and  extensor  carpi  radialis  longior  and  brevior 
muscles  and  then  enters  the  substance  of  the  supinator  (brevis)  through  which  it 
passes  to  supply  the  extensor  muscles  on  the  back  of  the  forearm  and  terminates  in  a 
gangliform  enlargement  on  the  back  of  the  wrist.  It  supplies  all  the  muscles  on  the 
back  of  the  forearm  except  the  anconeus,  brachioradialis,  and  extensor  carpi  radialis 
longior,  which  are  supplied  directly  from  the  radial  (musculospiral)  nerve.  In 
removing  the  head  of  the  radius,  in  resection  of  the  elbow,  the  supinator  (brevis)  is  to 
be  carefully  raised  from  the  bone  so  as  to  carry  the  nerve  with  it  and  a\'oid  injuring  it. 
Injury  to  this  nerve  causes  paralysis  of  the  extensors,  and  wrist-drop  follows. 

The  superficial  branch  {radial^  is  purely  a  nerve  of  sensation.  It  passes  down 
almost  in  a  straight  line  and  lies  to  the  outer  side  of  the  radial  «&rtery  at  the  junction 
of  its  upper  and  middle  thirds.  It  lies  alongside  of  the  artery  to  its  outer  side  in  its 
middle  third  and  then,  about  7  or  8  cm.  (3  in.)  above  the  wrist,  quits  the  artery, 
passes  beneath  the  tendon  of  the  brachioradialis,  and  divides  into  two  branches  which 
supply  sensation  to  the  dorsal  (radial)  side  of  the  hand  and  fingers  (Fig.  374,  p.  361). 

In  operating  on  the  radial  artery  in  the  middle  third  of  the  forearm  care  should 
be  exercised  not  to  include  the  nerve  in  the  ligature  with  the  artery. 

FRACTURES  OF  THE  FOREARM. 

Fractures  of  the  forearm  may  involve  either  the  radius  or  ulna,  or  both.  The 
radius  is  the  bone  most  often  broken.  The  preservation  of  the  interosseous  space 
and  functions  of  pronation  and  supination  are  prominent  points  in  treatment. 

Fractures  of  Both  Bones. — These  fractures  occur  either  from  a  direct  blow 
on  the  part  or  are  due  to  violence  in  falling  on  the  outstretched  hand.  They  usually 
occur  in  the  middle  or  lower  third.  The  character  of  the  displacement  depends 
more  on  the  manner  in  which  the  injury  is  produced  than  on  the  action  of  the 
muscles,  though  in  some  cases  they  also  have  some  influence. 

The  main  function  of  the  forearm  in  addition  to  that  of  serving  as  a  pedestal  or 
support  for  the  hand  is  to  perform  the  movements  of  pronation  and  supination.  It 
is  these  movements  that  are  most  apt  to  be  impaired  in  cases  of  fracture.  When 
both  bones  are  fractured  the  interosseous  membrane  still  remains,  running  transversely 
from  one  bone  to  that  of  the  opposite  side.  Therefore,  while  it  is  common  enough  to 
find  the  fractured  ends  displaced  toward  one  another,  thus  narrowing  or  obliterating 
the  space  between  them,  one  never  sees  a  displacement  of  the  fragments  produc- 
ing a  widening  of  the  interosseous  space.  In  fracture  of  both  bones  four  types  of 
deformity  or  combinations  of  these  types  are  found. 

1.  The  fractured  ends  of  the  distal  or  proximal  fragments  may  preserve  approx- 
imately their  normal  position  to  one  another  but  be  displaced  either  anteriorly  or 
posteriorly  or  else  to  one  side.  When  this  is  the  case  the  displacement  is  one  simply 
of  overlapping.  If  the  fragments  are  displaced  laterally  from  one  another  then  the 
tension  of  the  muscles  draws  the  fragments  together  and  causes  them  to  o\  erlap. 
There  is  no  special  direction  which  this  displacement  may  take.  The  lower  frag- 
ments may  be  either  in  front  or  behind  or  to  either  side  of  the  upper  ones.  The 
position  of  the  fragments  varies  according  to  the  direction  of  the  fracturing  force. 

This  displacement  is  to  be  remedied  by  traction  on  the  hand  to  overcome  the 
muscles  and  bring  the  broken  ends  opposite  one  another,  and  then  by  direct  pressure 
pushing  them  as  completely  as  possible  back  into  their  normal  position. 

The  shafts  of  both  bones  have  muscles  arising  from  them  on  both  their  anterior 
and  posterior  surfaces  dnd  the  sharp  fractured  ends  of  the  bones  not  infrequently  get 
stuck  in  the  muscular  fibres  and  so  prevent  proper  approximation;  non-union  may 
be  produced  by  this  cause. 

2.  The  fractured  ends  of  the  distal  or  proximal  fragments  may  be  displaced 
toward  one  another,  thus  lessening  or  even  obliterating  the  interosseous  space.    When 


322  APPLIED    ANATOMY. 

the  bones  are  intact  they  rest  on  one  another  at  their  ends,  leaving  a  space  between 
across  which  stretches  the  interosseous  membrane.  The  action  of  this  membrane  in 
preventing  a  separation  of  the  fragments  has  aheady  been  pointed  out,  and  the 
influence  on  the  fragments  of  pronation  and  supination  will  be  discussed  further  on. 
The  two  bones, — radius  and  ulna, — traverse  the  forearm  from  the  elbow  to  the 
wrist  like  two  bridges,  when  they  are  broken  they  naturally  fall  inward  toward  one 
another.  This  approximation  of  the  fragments  is  aided  by  the  muscles,  particularly 
the  pronators  and  the  brachioradialis. 

The  pronator  quadratus  and  teres  both  pass  from  the  ulna  to  the  radius,  the 
one  at  the  lower  and  the  other  at  the  upper  portion  of  the  forearm.  When  they 
contract  they  naturally  tend  to  draw  the  bones  toward  one  another.  The  brachio- 
radialis, arising  from  the  lateral  (external)  supracondylar  ridge  of  the  humerus 
and  inserting  into  the  base  of  the  styloid  process  of  the  radius,  by  its  contraction 
tends  to  tilt  the  upper  end  of  the  lower  fragment  toward  the  ulnar  side. 

Pressure  on  the  bones  by  bandages  wound  around  the  part  likewise  causes  them  to 
encroach  on  the  interosseous  space,  hence  the  desirability  of  splints  which  are  wider 
than  the  forearm  so  that  lateral  pressure  on  the  bones  by  the  bandages  is  prevented. 

3.  The  fragments  may  be  rotated  on  one  another  in  the  direction  of  pronation 
or  supination  and,  becoming  united  in  this  misplaced  position,  render  the  normal 
movements  of  rotation  either  much  restricted  or  altogether  impossible. 

This  axial  rotary  displacement  is  due  either  to  the  lower  fragments  being 
dressed  in  a  position  of  pronation  or  to  muscular  action.  As  has  already  been 
pointed  out  (see  movements  of  pronation  and  supination,  page  314),  in  performing 
the  movements  of  pronation  and  supination  the  ulna  is  the  fixed  bone  and  the  radius 
is  the  movable  one.  When  the  hand  is  pronated  the  radius  crosses  the  ulna 
obliquely  and  lies  almost  or  quite  in  contact  with  it,  thus  obliterating  the  inter- 
osseous space.  When  the  hand  is  in  a  position  of  middle  or  full  supination  the  bones 
are  widely  separated.  When  fractures  are  treated  in  the  prone  position  it  is  recog- 
nized that  the  callus  may  bind  the  bones  together  in  their  approximated  condition 
and  a  loss  of  motion  will  result. 

This  is  one  reason  why  it  is  always  required  to  treat  these  fractures  with  the 
hand  midway  between  supination  and  pronation  or  in  complete  supination,  in  which 
position  the  bones  are  widely  separated.  The  influence  of  the  supinator  muscles,  as 
was  pointed  out  by  Lonsdale,  is  also  important.  As  has  already  been  stated,  the 
supinators  are  stronger  than  the  pronators.  When  the  fracture  occurs  above  the  in- 
sertion of  the  pronator  radii  teres  the  upper  fragment  is  rotated  outward  by  the 
biceps  and  supinator  (brevis).  There  are  no  muscles  to  oppose  them.  On  this 
account  it  is  necessary  to  dress  the  fracture  with  the  hand  supinated.  When  the  bones 
are  broken  below  the  middle  of  the  forearm  the  pronator  radii  teres  remains  attached 
to  the  upper  fragment  and  tends  to  oppose  the  supinating  action  of  the  biceps  and 
supinator  (brevis).  Therefore  the  fracture  is  treated  with  the  hand  midway 
between  pronation  and  supination.  A  diminution  or  loss  of  the  power  of  pronation 
and  supination  is  a  common  sequel  of  fractures  of  the  forearm  and  is  due  either  to 
an  interference  with  the  movement  of  the  bones  by  callus  or  displaced  fragments  or 
by  supination  of  the  upper  fragment.  It  is  favored  by  treating  the  arm  in  an 
unfavorable  position. 

4.  The  fragments  may  be  inclined  toward  one  another,  producing  an  angular 
deformity.  Simple  bending  at  the  site  of  injury  produces  this  displacement.  It  is 
liable  to  occur  if  a  narrow  band  or  sling  is  used  to  support  the  injured  member.  If 
the  hand  is  supported  by  the  sling  the  arm  sags  at  the  seat  of  fracture.  If  the  fore- 
arm is  supported  at  the  site  of  fracture  the  hand  falls  and  an  angular  deformity 
again  occurs.  Treatment  of  the  fracture  with  the  hand  in  a  supine  position  on  a 
splint  with  a  long  sling  reaching  and  supporting  the  entire  length  of  the  forearm  will 
obviate  and  prevent  the  deformity. 

Fractures  of  the  Shaft  of  the  Radius. — Fractures  of  the  shaft  of  the  radius 
are  not  common.  They  are  produced  by  both  direct  and  indirect  injury.  The  hand 
is  attached  to  and  articulates  mainly  with  the  radius,  so  that  in  falls  on  the  hand  the 
force  is  transmitted  to  the  radius,  and  the  shaft  of  the  bone  is  not  infrequently 
fractured  in  this  manner. 


THE   FOREARM. 


323 


These  fractures  are  of  interest  from  an  anatomical  point  mainly  on  account  of 
the  influence  of  rotation  and  muscular  action  in  displacing  the  fragments.      The  fore- 
arm possesses  the  movement  of  rotation;  the  radius  is  the  movable  bone  and  rotates 
around  the  ulna,  hence  when  it  is  broken 
its  fractured  ends  are  readily  displaced. 
Fractures  of  this  bone  are  to  be  treated 
with  the  hand  in  half  or  full  supination 
because  in  these  positions  the  interosse- 
ous space  is  preserved.      In   pronation 
the  radius  crosses  the  ulna  obliquely  and 
lies  close  upon  it  and  is  then  most  liable 
to  be  bound   to  it  by  callus.      A   cer- 
tain amount  of  callus  or  deformity  may 
occur  without  interfering  with  the  ulna 
opposite. 

It  should  also  not  be  forgotten  that 
most  muscles  have  more  than  one  ac- 
tion. The  biceps  is  both  a  flexor  and 
supinator.  The  brachioradialis  flexes, 
supinates,  and  exerts  a  directly  upward 
traction  on  the  outer  surface  of  the  lower 
end  of  the  radius. 

The  fractures  of  the  shaft  of  the 
radius  may  be  divided  into  those  above 
and  those  below  the  insertion  of  the  pro- 
nator radii  teres.  This  muscle  inserts 
by  a  comparatively  small  tendon  into 
the  outer  and  posterior  surface  of  the 
middle  of  the  radius. 

Fractures  above  the  Insertion  of  the 
Pronator  Radii  Teres. — ^When  the  bone 
is  fractured  above  the  pronator  radii 
teres  insertion,  and  below  the  tubercle, 
the  upper  fragment  is  drawn  forward 
and  rotated  outward  by  the  biceps.  If 
the  fracture  is  down  close  to  the  upper 
edge  of  the  insertion  of  the  pronator 
radii  teres  the  supinator  (brevis)  will 
assist  in  the  supination.  The  lower  frag- 
ment will  be  pronated  by  the  pronator 
radii  teres  and  quadratus.  It  will  be 
drawn  toward  the  ulna  by  the  teres, 
quadratus,  and  also  by  the  action  of  the 
brachioradialis.  The  pronator  radii  teres 
will  also  tend  to  draw  the  lower  frag- 
ment anteriorly.  The  injury  is  to  be 
treated  with  the  elbow  flexed  to  relax 
the  biceps  and  in  a  fully  supinated  posi- 
tion (Fig.  332). 

Fractures  below  the  Insertion  of  the 
Pronator  Radii  Teres. — When  the  frac- 
ture is  below  the  insertion  of  the  pro- 
nator radii  teres  and  above  the  pronator 
quadratus  we  have  the  lower  fragment 

drawn  toward  the   ulna  by  the  pronator  quadratus  and   the  brachioradialis 
quadratus  also  tends  to  pronate  the  hand  (Fig.  333). 

The  upper  fragment  is  displaced  anteriorly  by  the  flexing  action  of  both  the  biceps 
and  pronator  radii  teres.  The  supinator  (brevis)  and  biceps  both  tend  to  supinate 
it  and  the  pronator  radii  teres  to  pronate  it.     This  tends  to  place  the  upper  fragment 


-Biceps 


-Supinator  (brevis) 

_Brachioradialis  (supi- 
"nator  longus) 


"Pronator  radii  teres 


-Upper  fragment 


■  Lower  fragment 


Deep  flexor  muscles 


Pronator  quadratus 


Fio.  332. — Fracture  of  the  shaft  of  the  radius  above 
the  insertion  of  the  pronator  radii  teres  muscle.  The 
upper  fragment  is  rotated  outward  by  the  biceps  and 
supinator  muscles. 


The 


324 


APPLIED   ANATOMY. 


midway  between  pronation  and  supination.  All  fractures  of  the  radius  are  to  be  treated 
with  the  elbow  flexed  to  relax  the  biceps  muscle.  It  is  to  be  marked  that  the 
position  of  the  lower  fragment  follows  the  position  of  the  hand  in  pronation  and 
supination.  Also  that  by  bending  the  hand  toward  the  ulnar  side  the  lower  fragment 
tends  to  be  tilted  away  from  the  ulna  and  thus  the  interosseous  space  is  increased. 


Biceps- 


Brachxoradialis 


Pronator 
radii  teres" 


Site  of  fracture  ■ 
Brachioradialis- 


Pronator 
quadratus  - 


Pronator 
quadratus 


FiG-  333- — Fracture  of  the  radius  just  below  the 
insertion  of  the  pronator  radii  teres  muscle.  The 
upper  fragment  is  displaced  directly  forward  in  a 
position  midway  between  pronation  and  supination. 


Fig.  334. — -Fracture  below  the  middle  of  the  shaft  of 
the  ulna,  the  lower  fragment  drawn  toward  the  radius 
by  the  pronator  quadratus  muscle. 


Pressure  with  the  thumb  and  fingers  between  the  bones  tends  to  increase  the  inter- 
osseous space  and  to  some  extent  to  counteract  the  action  of  the  brachioradialis. 

On  account  of  the  upper  fragment  assuming  a  middle  position  the  fracture  is 
dressed  in  this  position  with  the  thumb  upward — an  internal  angular  splint  is  used. 
Some  surgeons  prefer  using  the  position  of  full  supination. 

The  difference  in  the  width  of  the  interosseous  space  when  the  hand  is  in  full 
supination  and  when  it  is  in  semisupination,  though  it  may  be  slightly  in  favor  of  the 
latter  position,  is  too  little  to  give  it  any  preference  on  that  account. 


THE   FOREARM.  325 

Fractures  of  the  Shaft  of  the  Ulna. — The  shaft  of  the  ulna  is  more  often 
broken  by  direct  violence  than  is  the  shaft  of  the  radius.  When  the  arm  is  raised  to 
ward  off  a  threatened  blow  the  thumb  is  toward  the  body  and  it  is  the  ulna  which  is 
presented  externally  to  receive  the  impact  of  the  blow,  hence  its  more  frequent 
injury.  There  are  two  main  sites  of  injury,  one  just  below  its  middle  and  the  other 
a  short  distance  below  the  elbow-joint,  about  at  the  junction  of  its  middle  and  upper 
thirds.  The  former  results  from  the  fact  that  the  bone  below  the  middle  is  smaller 
and  weaker  than  it  is  above  and  is  not  so  well  covered  by  muscles. 

Fractures  just  Below  the  Middle  of  the  Shaft  of  the  Ulna. — The  bones  of  the 
forearm  act  as  props  to  separate  the  hand  and  elbow.  The  hand  is  attached  to  the 
radius  and  the  radius  rests  on  the  capitellum  of  the  humerus,  therefore  even  when  the 
ulna  is  fractured  as  long  as  the  radius  and  attachments  of  the  hand  are  intact  there  is 
usually  but  little  overlapping  of  the  fragments. 

The  lower  fragment  is  most  often  displaced  to  the  radial  side.  This  is  due  to 
the  action  of  the  pronator  quadratus  muscle  (Fig.  334). 

The  upper  fragment  articulating  with  the  humerus  by  a  pure  hinge-joint  cannot 
be  displaced  laterally,  but  the  radius  and  hand  can  move  bodily  toward  the  ulna, 
being  favored  in  so  doing  by  the  pronator  radii  teres.     Thus  it  is  seen  that  both 


External  condyle- 


Tendon  of  triceps 

Lower  fragment  Upper  fragment  Anconeus  covered  by  expansion 

of  ulna  of  ulna  of  the  tendon  of  the  triceps 

Fig.  335. — Fracture  through  the  upper  third  of  the  ulna  viewed  from  the  outer  side. 

Upper  and  lower  fragments  have  a  tendency  to  incline  toward  the  radius  and  so 
obliterate  the  interosseous  space  and  interfere  with  rotation. 

As  to  whether  the  lower  or  upper  fragment  will  be  nearer  to  the  radius  will 
depend  upon  the  direction  of  the  line  of  fracture.  If  this  is  from  within  downward 
and  outward,  as  is  the  more  usual,  then  the  lower  fragment  will  be  to  the  radial  side 
of  the  upper  one. 

The  treatment  of  fractures  in  this  locality  should  be  with  the  hand  placed  in  the 
position  of  full  supination.  Hamilton  ("Fractures  and  Dislocations,"  page  319) 
stated  that  he  had  three  times  seen  supination  lessened  in  this  injury  but  never  pro- 
nation. The  ulna  is  to  be  pushed  away  from  the  radius  by  pressure  made  between 
them  with  the  thumb  and  fingers  and  the  hand  bent  toward  the  radial  side. 

Fracture  at  the  Upper  Third.  —  The  radius  articulates  with  the  upper  end 
of  the  ulna  in  the  lesser  sigmoid  cavity.  Immediately  below  this  is  a  depression  in 
the  ulna  called  the  bicipital  hollow,  intended  to  accommodate  the  bicipital  tubercle 
when  the  forearm  is  pronated.  At  this  point  the  bone  is  slightly  narrowed  and 
then  widens  ag^ain  toward  the  middle.  This  constricted  part  is  7  or  8  cm.  (3  in.) 
below  the  tip  of  the  olecranon  process  and  the  spot  where  fracture  is  likely  to  occur. 
When  fracture  does  occur  here,  if  displacement  is  marked,  it  produces  characteristic 
lesions.     The  upper  fragment  may  be  displaced  either  posteriorly  or  anteriorly. 


326 


APPLIED    ANATOMY. 


The  carrying  angle  (page  282)  formed  by  the  line  of  the  arm  with  the  line  of 
the  forearm,  depends  on  the  integrity  of  the  humerus  and  ulna  and  their  proper 
articulation.  If  the  ulna  is  broken  high  up  the  forearm  is  deprived  of  its  support  on 
the  inner  side  and  it  sags  inward,  thus  approximating  the  bones,  obliterating  the 
interosseous  space,  and  diminishing  the  carrying  angle.  In  treatment  care  should 
be  taken  that  the  forearm  be  not  allowed  to  incline  toward  the  inner  side. 

Displacejnent  Posterior. —  When  the  displacement  is  posterior  the  lower  end  of 
the  upper  fragment  is  tilted  backward  by  the  contraction  of  the  triceps  muscle.  This 
causes  a  marked  projection  on  the  back  of  the  forearm  below  the  elbow  (Fig.  335). 

In  treating  this  injury  the  forearm 
should  be  placed  in  at  least  partial  ex- 
tension (complete  extension  is  usually 
not  necessary)  so  as  to  relax,  the  triceps 
muscle. 

Displacement  Anterior. — When  a 
person  receives  a  blow  in  the  region  of 
the  junction  of  the  upper  and  middle 
thirds  of  the  ulna  on  its  posterior  sur- 
face the  fragments  are  pushed  forward 
and  an  angular  deformity  is  produced, 
the  apex  of  the  angle  pointing  toward 
the  anterior  surface.  The  force  of  the 
blow  is  not  expended  entirely  on  the 
ulna  but,  having  broken  it,  continues 
and  pushes  or  dislocates  the  radius  for- 
ward (Fig.  336).  _ 

In  these  injuries  the  fracture  of  the 
ulna  is  readily  recognized,  but  the  dis- 
location of  the  head  of  the  radius  is  often 
overlooked.  If  the  dislocation  is  not 
reduced  subsequent  flexion  of  the  elbow 
will  not  be  possible  much  if  any  beyond 
a  right  angle.  The  contraction  of  the 
biceps  not  only  favors  this  luxation  by 
pulling  the  radius  forward  but  tends  to 
cause  it  to  recur  after  replacement. 

Reduction  is  to  be  attempted  by 
supinating  and  flexing  the  foi'earm  to 
relax  the  biceps  and  making  direct 
pressure  anteroposteriorly  on  the  radius 
to  force  the  head  back  into  place.  The  radius  may  be  kept  in  place  by  dressing 
the  arm  with  the  elbow  in  a  position  of  complete  flexion. 


Fig.  336. — Fracture  of  the  upper  third  of  the  ulna, 
with  anterior  angular  displacement  of  the  fragments  and 
anterior  dislocation  of  the  head  of  the  radius. 


AMPUTATION   OF   THE   FOREARM. 

The  lower  half  of  the  forearm  is  so  largely  tendinous  that  musculocutaneous 
flaps  are  unsuitable  ;  by  the  time  the  tendons  are  cut  short  there  is  little  tissue  left 
but  skin,  superficial  and  deep  fascia,  and  a  few  muscular  fibres. 

Amoutation  should  be  performed  as  low  down  as  one  can  so  as  to  save  as  much 
as  possible.  Artificial  appliances,  so  useful  in  the  lower  extremity,  are,  practically, 
of  little  value  in  the  upper.  The  preservation  of  the  power  of  pronation  and  supi- 
nation is  to  be  accomplished  when  the  condition  permits.  The  pronator  radii  teres 
has  its  insertion  in  the  middle  of  the  radius  and  if  the  division  of  the  bone  is  below 
that  point  rotary  movements  will  be  preserved. 

The  surgeon  should  be  acquainted  with  the  position  of  the  main  arteries  and 
nerves.  Four  arteries  will  require  ligation  :  the  radial,  ulnar,  volar  (anterior),  and 
dorsal  (posterior)  interosseous.  Their  position  as  well  as  that  of  the  nerves  will 
vary  accordingly  to  the  site  of  the  amputation.  The  median  and  ulnar  are  the  only 
nerves  that  require  shortening. 


THE  FOREARM. 


327 


Amputation  Through  the  Upper  Third. — The  radial  artery  is  to  be  looked 
for  near  the  surface  under  the  deep  fascia,  just  beneath  the  edge  of  the  brachioradialis 
muscle. 

The  ulnar  artery  lies  between  the  superficial  and  deep  fiexor  muscles  somewhat 
toward  the  ulnar  side  of  the  median  line. 

The  volar  interosseous  artery  lies  in  front  of  the  interosseous  membrane. 

The  dorsal  interosseous  lies  between  the  superficial  and  deep  muscles  on  the  back 
of  the  forearm  more  toward  the  ulnar  side. 

The  median  nerve  is  to  be  sought  in  the  middle  line  of  the  forearm  below  the 
superficial  flexor  muscles. 

The  ulnar  nerve  lies  to  the  ulnar  side  of  the  ulnar  artery  on  a  level  with  it  and 
beneath  the  flexor  carpi  ulnaris  muscle. 

Amputation  Through  the  Middle  Third. — The  radial  artery  lies  beneath 
the  deep  fascia  in  front  of  the  radius  along  the  inner  edge  of  the  brachioradialis. 


Superficial  layer 
of  flexor  muscles 

Ulnar  artery 

Ulnar  nerve 

Deep  layer  of 

flexor  muscles' 

Anterior  (volar)  interosseous. 

artery  and  nerve 


Ulna, 


Flexor  carpi  radialis 
Radial  artery 

Median  nerve 

Brachioradialis  (supinator  longus) 

Radial  nerve 

Pronator  radii  teres 
Extensor  carpi  radialis  longior 

Radius 

Extensor  carpi  radialis  brevior 


Extensor  muscles  of  fingers 
Fig.  337. — Amputation  about  the  middle  of  the  forearm. 

The  ulnar  artery  here  becomes  more  superficial  and  lies  beneath  the  radial  edge 
of  the  flexor  carpi  ulnaris  muscle. 

The  volar  interosseous  is  found  lying  on  the  anterior  surface  of  the  interosseous 
membrane  or  the  thin  edge  of  the  flexor  profundus. 

The  dorsal  interosseous  lies  posterior  to  the  membrane  between  the  superficial 
and  deep  extensor  muscles. 

The  median  nerve  is  directly  in  the  midline  beneath  the  flexor  sublimis  and 
above  the  flexor  profundus  digitorum. 

The  ulnar  nerve  lies  to  the  radial  side  of  the  ulna,  to  the  ulnar  side  of  the  ulnar 
artery,  and  under  the  flexor  carpi  ulnaris  muscle  (F"ig.  337). 

Amputation  Through  the  Lower  Third. — The  radial  artery  lies  beneath 
the  deep  fascia  between  the  flexor  carpi  radialis  and  brachioradialis. 

The  ulnar  artery  lies  to  the  ulnar  side  under  the  deep  fascia  and  at  the  edge  of 
the  flexor  carpi  ulnaris  muscle. 

The  volar  and  dorsal  interosseous  arteries  are  too  small  to  require  ligation. 

The  median  nerve  lies  beneath  the  palmaris  longus  muscle.  At  the  wrist  it  lies 
beneath  the  interval  between  it  and  the  flexor  carpi  radialis. 

The  ulnar  nerve  is  superficial  along  the  edge  of  the  flexor  carpi  ulnaris  and 
accompanies  the  ulnar  artery  along  its  medial  (ulnar)  side. 


328  ^^^       APPLIED   ANATOMY. 

OPERATIONS  ON   THE  BONES   AND  OTHER  STRUCTURES  OF  THE 

FOREARM. 

The  forearm  may  require  to  be  operated  on  for  disease  or  injuries  of  the  bones, 
tumors,  foreign  bodies,  wounds,  etc.  In  operating  on  this  region  of  the  body  it  is  to 
be  constantly  borne  in  mind  that  it  contains  a  multitude  of  structures  each  of  which 
is  essential  to  the  proper  performance  of  some  special  function.  Injury  to  these 
structures  is  followed  by  a  corresponding  functional  disability.  Attempts  at  brilliant 
operating  are  out  of  place  and  the  surgeon  should  be  exact,  careful,  and  even  tender 
in  his  handling  of  the  various  structures. 

The  forearm  is  mainly  nourished  by  the  volar  and  dorsal  interosseous  arteries;  the 
radial  and  ulnar  pass  through  it  to  nourish  the  hand.     These  latter  are  to  be  avoided. 

The  nerves  that  supply  the  forearm  are  given  of?  high  up  near  the  elbow,  hence 
they  are  not  usually  in  danger  of  injury.  The  median,  ulnar,  and  superficial  branch 
of  the  radial  nerve  pass  to  the  hand  and  they,  if  possible,  are  to  be  avoided. 

It  is  therefore  evident  that  as  far  as  the  arteries  and  nerves  are  concerned  oper- 
ations in  the  lower  part  of  the  forearm  are  less  dangerous  than  those  in  the  upper. 
With  the  muscles  it  is  just  the  opposite.  In  the  lower  half  the  muscles  become  ten- 
dinous and  soon  form  groups  or  masses  of  tendons.  These  tendons  are  separated  by 
thin  connective-tissue  sheaths  or  synovial  membrane  which  allow  them  to  move  freely 
as  the  muscles  contract.  Any  interference  with  these  sheaths  or  their  contents 
causes  an  outpouring  of  inflammatory  material  that  binds  them  together  and  fetters 
their  action.  As  healing  takes  place  contraction  sets  in  and  the  patient  is  left  with  a 
useless  claw-like  hand.  For  these  reasons  large  incisions  and  displacements  and 
interference  with  tendons  are  to  be  avoided  whenever  possible. 

As  the  muscles  mostly  run  longitudinally  the  incisions  should  also  be  longitu- 
dinal. Division  of  the  superficial  veins  is  not  liable  to  cause  trouble,  but  the  large 
radial,  median,  or  ulnar  veins  on  the  anterior  surface  may  be  plainly  visible  and  then 
the  incision  should  be  made  so  as  to  avoid  wounding  them. 

The  only  superficial  nerve  to  be  so  avoided  is  the  superficial  branch  of  the 
radial.  It  is  alongside  of  the  radial  artery  in  its  middle  third,  but  about  7  or  8  cm. 
(3  in. )  above  the  wrist  it  leaves  the  artery  and  winds  under  the  brachioradialis  to  go 
down  the  outer  and  posterior  surface  of  the  radius.  It  is  here  to  be  looked  for  and 
avoided,  as  it  furnishes  sensation  to  the  thumb,  index,  middle,  and  half  of  the  ring 
fingers. 

If  it  is  desired  to  penetrate  the  muscles  their  direction  is  to  be  remembered. 
The  superficial  flexor  muscles  arise  from  the  internal  condyle,  hence  the  incision 
should  point  upward  toward  it.  The  direction  of  the  pronator  radii  teres  is  from 
the  internal  condyle  to  the  middle  of  the  radius.  The  deep  fiexors  are  parallel  with 
the  bones. 

Posteriorly  the  extensor  group  of  muscles  tends  toward  the  external  condyle. 
A  third  group  on  the  radial  side  comprises  the  brachioradialis  and  the  extensor  carpi 
radialis  longior  and  brevior.  The  tendon  of  the  first  lies  on  the  outer  surface  of  the 
radius  with  the  other  two  immediately  posterior  to  it.  Crossing  the  posterior  and 
outer  surface  of  the  radius  in  its  lower  third  are  the  extensor  ossis  metacarpi  pollicis 
and  extensor  brevis  pollicis  tendons. 

If  it  is  desired  to  reach  the  bones  the  ulna  can  be  exposed  posteriorly  where  it 
is  subcutaneous  in  its  entire  length  by  an  incision  between  the  flexor  carpi  ulnaris 
and  extensor  carpi  ulnaris.     The  deep  fascia  is  attached  to  the  bone  at  this  point. 

If  it  is  desired  to  expose  the  radius,  H.  Morris  {C/m.  Soc.  Trans.,  vol.  x,  p.  138) 
has  advised  going  in  between  the  brachioradialis  and  the  extensor  carpi  radialis 
longior.  He  used  the  superficial  branch  of  the  radial  nerve  as  a  guide  to  the  desired 
interspace. 

If  an  incision  were  made  upward  from  the  outer  surface  of  the  styloid  process  of 
the  radius  one  would  first  encounter  the  tendons  of  the  extensor  brevis  pollicis  and 
extensor  ossis  metacarpi  pollicis  muscles.  These  being  displaced  posteriorly  would 
reveal  the  brachioradialis  tendon  crossing  from  beneath  the  posterior  border  of  the 
radius;  5  to  7  cm.  (2  to  3  in.)  above  the  styloid  process  would  be  the  superficial 


THE   FOREARM.  329 

branch  of  the  radial  nerve.  Following  the  nerve  and  edge  of  the  brachioradialis 
tendon  would  lead  to  the  interspace  between  it  and  the  extensor  carpi  radialis 
muscle  posteriorly.  When  the  middle  of  the  forearm  was  reached  the  insertion  of 
the  pronator  teres  would  be  encountered,  and  from  that  point  up  the  bone  would 
be  covered  by  the  supinator  (brevis). 

Operations  on  the  median  nerve  (page  319)  and  the  ulnar  nerve  (page  320) 
have  already  been  alluded  to. 

In  operations  involving  the  upper  third  of  the  radius  the  deep  branch  of  the 
radial  (posterior  interosseous)  nerve  is  liable  to  be  wounded  as  it  passes  through  the 
supinator  (brevis)  muscle.  It  is  best  avoided  by  elevating  the  muscle  from  the 
bone  and  raising  the  nerve  along  with  it,  for  it  does  not  rest  immediately  on  the 
bone  but  has  some  muscular  fibres  intervening. 

The  arteries  have  already  been  sufficiently  described. 

PUS   BENEATH   THE   DEEP  FASCIA. 

The  deep  fascia  of  the  forearm  is  continuous  with  that  of  the  arm.  It  forms  a , 
complete  covering  for  the  muscles  and  sends  septa  between  them.  It  is  especially 
strong  posteriorly.  It  is  attached  to  the  medial  and  lateral  condyles  of  the  humerus, 
the  sides  of  the  olecranon  process  and  the  whole  length  of  the  ulna  posteriorly. 
Below  the  medial  condyle  anteriorly  it  is  strengthened  by  the  bicipital  fascia.  In 
the  antecubital  fossa  it  is  pierced  by  a  large  communicating  vein  which  connects  the 
superficial  and  deep  veins.  Toward  its  lower  end  posteriorly,  it  is  strengthened 
by  transverse  fibres  and  becomes  attached  to  the  longitudinal  ridges  on  the  radius 
and  blends  with  the  posterior  annular  ligament. 

Below  anteriorly  it  is  thin  and  forms  a  covering  for  the  tendons  of  the  palmaris 
longus  and  flexor  carpi  radialis  muscles  and  at  the  wrist  blends  with  the  annu- 
lar ligament  beneath.  This  latter,  as  pointed  out  by  Davies  CoUey  ("Morris's 
Anatomy,"  page  311),  is  a  continuation  of  the  layer  of  fascia  covering  the  flexor 
sublimis  digitorum. 

When  infection  in\olves  the  deep  tissues  of  the  forearm  the  pus,  being  hindered 
from  going  externally  by  the  fibrous  septa  between  the  various  layers  of  muscles  as 
well  as  the  deep  fascia  itself,  tends  to  burrow  up  and  down  the  arm.  If  in  the  upper 
portion  of  the  forearm,  it  tends  to  point  in  the  antecubital  fossa.  If  lower  down,  it  tends 
to  come  to  the  surface  on  the  radial  side  between  the  flexor  carpi  radialis  and  brachio- 
radialis or  toward  the  ulnar  side  between  the  palmaris  longus  and  flexor  carpi  ulnaris. 

The  three  structures, — the  tendons  of  the  palmaris  longus  and  flexor  carpi  radialis 
and  the  median  nerve, — form  a  solid  barrier  anteriorly  which  inclines  the  pus  to  one 
side.  Above  posteriorly  it  may  work  its  way  upward  behind  the  internal  condyle, 
following  the  ulnar  nerve. 

The  fibrous  septa  of  the  various  muscles  hinder  the  progress  of  pus  laterally,  and 
the  attachment  of  the  deep  fascia  to  the  ulna  prevents  its  passing  around  the  arm  at 
that  point.  The  many  pockets  formed  by  the  pus  in  its  burrowing  between  the 
muscles  render  these  abscesses  difficult  to  drain  and  tedious  in  healing. 

Should  infection  from  the  thumb  travel  up  the  flexor  longus  poUicis  tendon, 
when  it  reaches  above  the  wrist  it  is  directly  beneath  the  tendon  of  the  flexor  carpi 
radialis.  In  such  a  case  an  incision  should  be  made  along  the  radial  (outer)  edge  of 
the  tendon,  taking  care  not  to  wound  the  radial  artery  still  farther  out.  If  pus  infects 
the  forearm  by  following  up  the  flexor  tendons  of  the  fingers  beneath  the  anterior 
annular  ligament,  it  shows  itself  above  the  wrist  between  the  palmaris  longus  and 
flexor  carpi  ulnaris  tendons  and  can  here  be  incised.  If  it  is  desired  to  introduce  a  drain 
beneath  the  flexor  muscles,  an  incision  may  be  made  along  the  side  of  the  ulna  and  a 
forceps  passed  under  the  flexor  tendons  and  made  to  project  under  the  skin  of  the 
radial  side  where  a  counter  opening  can  be  made  and  the  drain  inserted.  (For  a  dis- 
cussion of  the  treatment  of  purulent  affections  of  the  hand  and  forearm  see  A.  B. 
Kavanel  :  "  Surgery,  Gynecology,  and  Obstetrics,"  1909,  p.  125,  vol.  viii.  No.  3.) 
Suppuration  around  these  tendons  is  very  serious,  as  the  effusion  binds  together  the 
tendons  and  irritates  the  nerves  and  produces  disabling  contractures  which  are  exceed- 
ingly difficult  to  remedy. 


APPLIED  ANATOMY. 


REGION  OF  THE  WRIST. 


By  the  wrist  is  meant  the  constricted  portion  of  the  upper  extremity  by  which 
the  hand  is  joined  to  the  forearm.  We  will  include  in  its  consideration  the  lower 
portion  of  the  forearm  for  about  4  cm.  ( i  ^  in. )  above  the  radiocarpal  joint,  and  the 


Fig.  338. — Sawn  section  through  the  lower  end  of  the  radius  to  show  its  cancellous  structure. 

joint  itself.  The  wrist  is  so  constructed  as  to  permit  of  the  movements  of  pronation 
and  supination  of  the  bones  of  the  forearm,  to  serve  as  a  support  for  the  hand,  and 
to  allow  movements  of  the  hand  in  various  directions. 


Radius 


Styloid  process 

Scaphoid 
Tuberosity  of  scaphoid 

Trapezium 

Ridge  on  trapezium 

Trapezoid 


Styloid  process 

Semilunar 

Cuneiform 

Pisiform 

■Os  magnum 

•Unciform 

•Unciform  process 


Fig.  339. — Anterior  view  of  the  lower  ends  of  the  radius  and  ulna  and  the  carpal  bones. 

BONES   OF   THE   WRIST. 

We  may  include  among  the  bones  of  the  wrist  the  lower  ends  of  the  radius  and 
ulna  and  the  first  row  of  bones  of  the  carpus, — the  scaphoid,  lunate  (semilunar), 
cuneiform,  and  pisiform. 


REGION   OF   THE   WRIST.  331 

Of  the  bones  of  the  forearm — the  radius  and  ulna — we  have  seen  that  at  the 
elbow  the  ulna  is  the  larger  of  the  two.  This  is  because  the  main  function  of  the 
ulna  is  to  act  as  a  support  to  the  parts  beyond.  The  radius  is  intended  mainly  as  a 
means  of  enabling  the  hand  to  perform  the  functions  of  pronation  and  supination. 
At  the  wrist  we  find  the  radius  supporting  the  hand  and  consequently  its  lower 
end  is  large  and  well  dcAeloped.  The  ulna,  on  the  contrary,  contributes  but  little  to 
the  support  of  the  hand  and  does  not  even  enter  directly  into  the  wrist-joint,  as  does 
the  radius  at  the  elbow-joint,  but  ser\'es  as  a  fixed  point  around  which  the  radius 
rotates.  The  functional  value  of  the  ulna  at  the  wrist  is  so  much  less  than  that  of 
the  radius  as  amply  to  account  for  its  diminished  size. 


Radius- 
Posterior  radial  or  thecal  tubercle 

Styloid  process  of  radius 

Scaphoid 

Trapezium 

Trapezoid 
Metacarpal  bone  of  the  thumb 


Ulna 


Head  of  ulna 


Styloid  process  of  ulna 
■Semilunar 

Cuneiform 


Os  magnum 
Unciform 


Fig.  340. — Posterior  view  of  the  lower  end  of  the  radius  and  ulna  and  the  carpal  bones. 


Lower  end  of  the  Radius. — The  lower  end  of  the  radius  is  large  and  spongy. 
The  compact  tissue  forms  a  quite  thin  superficial  layer  (Fig.  338).  Its  anterior 
surface  is  hollowed  out  to  receive  the  pronator  quadratus  muscle,  with  a  prominent 
articular  edge  to  which  is  attached  the  anterior  ligament  (Fig.  339). 

The  posterior  surface  is  convex  and  marked  with  a  number  of  ridges  with 
grooves  between  them  which  lodge  the  extensor  tendons  (Fig.  340).  In  its  middle 
is  a  prommence,  the  dorsal  radial  tubercle,  which  marks  the  position  of  the  extensor 
longus  pollicis  muscle.  On  its  inner  side  is  a  concave  articular  facet,  the  ulnar  notch 
{sigrnoid  cavity),  for  articulation  with  the  ulna;  it  is  plane  from  above  downward, 
thus  showing  that  it  permits  movement  in  one  direction  only,  like  a  hinge. 

Between  the  lower  edge  of  the  ulnar  notch  and  the  articular  surface  is  a  rough 
ridge  that  gives  attachment  to  the  triangular  interarticular  fibrocartilage. 


332 


APPLIED  ANATOMY. 


The  lower  or  radiocarpal  articular  surface  slopes  downward  and  outward  to  end 
in  the  styloid  process,  which  is  thereby  placed  lower  than  the  styloid  process  of  the 
ulna.  The  articular  surface  is  divided  into  two  facets:  the  outer  is  the  smaller, 
is  triangular  in  shape,  and  articulates  with  the  navicular  (^scaphoid)  bone;  the 
inner  or  larger  is  quadrilateral  and  articulates  with  the  lunate  {semilunar)  bone. 
The  styloid  process  at  its  base  or  upper  outer  portion  has  inserted  into  it  the  tendon 
of  the  brachioradialis  muscle.      To  its  tip  is  attached  the  external  lateral  ligament. 

The  Ulna. — The  lower  extremity  of  the  ulna  is  rounded  in  shape,  forming  its 
head,  with  the  styloid  j^rocess  projecting  downward  on  its  inner  and  posterior  aspect 
To  its  tip  is  attached  the  internal  lateral  ligament.      On  its  outer  side  is  a  rounded 
smooth  surface  for  articulation  with  the  ulnar  notch  of  the  radius.     The  inferior 
or  articular  surface  is  flat  and  rests  on  the  flat  interarticular  fibrocartilage. 

The  navicular  (scaphoid),  lunate  (semilunar),  cuneiform,  and  pisi- 
form bones  form  the  first  row  of  the  carpal  bones.  The  pisiform  rests  on  the 
anterior  surface  of  the  cuneiform  and  does  not  enter  into  the  articulations  between 
the  hand  and  bones  of  the  forearm. 

The  navicular  and  lunate  articulate  directly  with  the  lower  end  of  the  radius, 
but  the  cuneiform  articulates  with  the  under  surface  of  the  triangular  interarticular 
fibrocartilage. 


THE   INFERIOR   RADIO-ULNAR  ARTICULATION. 

The  joint  between  the  lower  ends  of  the  radius  and  ulna  embraces  not  only  the 
portion  between  these  two  bones  but  also  that  between  the  lower  end  of  the  ulna  and 


Radius- 


Radiocarpal  (wrist)  joint 

Scaphoid  — ,, 

External  lateral  ligament 


Ulna 


Pronator  quadratus 

Inferior  radio-ulnar  joint 

Triangular  fibrocartilage 

Semilunar 

Internal  lateral  ligament 

Cuneiform 
*L  Flexor  carpi  ulnaris  tendon 

Pisiform 


Fig.  341. — ^The  wrist-joint  and  inferior  radio-ulnar  articulation. 

the  upper  surface  of  the  triangular  fibrocartilage.  This  latter  is  attached  by  its  apex 
to  a  depression  on  the  outer  side  of  the  root  of  the  styloid  process  of  the  ulna,  and 
by  its  base  to  the  rough  line  on  the  radius  separating  the  radio-ulnar  from  the  radio- 
carpal articulation  (Fig.  341). 

The  Interarticular  Triangular  Fibrocartilage. — This  serves  as  the  main 
bond  of  union  between  the  lower  ends  of  the  radius  and  ulna.  It  is  strong  and 
blends  with  the  internal  lateral  ligament.  Thus  the  hand  has  an  attachment  to  the 
inner  side  of  the  radius  by  means  of  the  internal  lateral  ligament  and  triangular 
cartilage. 


REGION    OF   THE   WRIST. 


333 


The  Capsular  Ligament.  —  The  capsular  ligament  serves  to  retain  the  syno- 
vial fluid  in  the  joint.  It  is  thin  and  filmy  and  possesses  no  strength,  and  therefore 
is  useless  in  limiting  movements. 

Anterior  and  Posterior  Radio-ulnar  Ligaments. — These  ligaments  are 
simply  a  few  bands  which  pass  across  from  the  radius  to  the  ulna.  They  are  not 
strong  enough  to  be  efficient  in  limiting  mov'ements  of  the  bones. 

Movements. — As  has  already  been  pointed  out  (page  304) 
the  movements  of  pronation  and  supination  have  as  their  axis  a 
line  drawn  through  the  middle  of  the  head  of  the  radius,  the  styloid 
process  of  the  ulna,  and  the  ring  finger.  They  embrace  in  ordinary 
use  a  range  of  about  140  degrees  which  can  be  increased  by  forced 
effort  to  160  degrees  (Fig.  342). 

These  movements  are  limited  by  various  factors,  the  most 
prominent  being  in  pronation  the  contact  of  the  soft  parts  and 
bones,  as  the  radius  obliquely  overlies  the  ulna,  and  in  supination 
by  the  biceps  (the  most  powerful  of  the  supinators)  having  reached 
the  dead  centre. 

There  is  no  communication  between  the  radio-ulnar  joint 
above  and  the  radiocarpal  joint  below,  except  when,  as  occasion- 
ally happens,  the  triangular  cartilage  has  a  perforation. 

During  pronation  and  supination  the  lower  end  of  the  radius 
moves  with  the  hand,  but  the  lower  end  of  the  ulna  remains  at  rest: 
hence  it  is  that  the  styloid  process  of  the  radius  always  retains  the 
same  position  in  relation  to  the  hand.  When  it  is  desired  to  iden- 
tify the  styloid  process  of  the  radius,  one  needs  only  to  follow  the 
metacarpal  bone  of  the  thumb  up  to  the  snufl-box  at  the  upper 
edge  of  which  the  styloid  process  can  always  be  felt.  Also,  to 
identify  the  styloid  process  of  the  ulna,  one  must  not  use  the  hand 
as  a  guide  because  the  hand  changes  its  position  in  relation  to  the 
ulna;  but,  as  the  ulna  remains  quiet,  its  styloid  process  can  be 
found  by  following  the  posterior  surface  down  to  its  extremity. 

As    the    interarticular  triangular  cartilage  is  fastened  by  its 
base  to  the  ulnar  edge  of  the  radius  and  by  its  apex  to  the  base 
of  the  styloid  process  of  the  ulna,  it  travels  with  the  hand  in  the  movements  of 
pronation  and  supination. 


Fig. 3  42. — Axis  of  rota- 
tion. 


THE   RADIOCARPAL   OR   WRIST-JOINT. 

The  wrist-joint  is  formed  by  the  radius  and  triangular  cartilage  above  and  the 
navicular  (scaphoid),  lunate  (semilunar),  and  cuneiform  bones  below.  These  are 
joined  by  the  anterior,  posterior,  internal  and  external  lateral,  and  capsular  liga- 
ments. The  two  lateral  ligaments  are  strong,  well-defined  bands,  the  anterior  and 
posterior  ligaments  are  weaker  and  are  fused  with  the  capsular  ligament. 

The  internal  lateral  ligament  is  attached  above  to  the  tip  of  the  styloid 
process  of  the  ulna  and  the  tip  of  the  triangular  cartilage  ;  below  it  is  attached  to  the 
border  of  the  cuneiform  bone  and  is  continued  on  to  the  pisiform  bone. 

The  external  lateral  ligament  is  attached  above  to  the  tip  of  the  styloid 
process  of  the  radius  and  below  to  the  base  of  the  tubercle  of  the  navicular  bone. 

The  capsular  ligament  of  the  wrist-joint  is  composed  of  an  anterior  and  a 
posterior  portion  strengthened  by  the  two  lateral  ligaments  just  described.  The 
anterior  ligament  has  the  bulk  of  its  fibres  running  downward  and  inward  from  the 
edge  of  the  radius  to  the  palmar  surface  of  the  navicular,  lunate,  and  cuneiform 
bones.  It  is  stronger  than  the  posterior.  The  posterior  ligament  likewise  has 
its  fibres  running  downward  and  inward  to  be  attached  to  the  first  row  of  carpal 
bones. 

Movements. — The  wrist  is  classed  as  a  biaxial  diarthrosis  or  condyloid  joint. 
This  means  that  it  is  a  double  hinge-joint  having  movements  around  two  axes, 
one  anteroposterior  and  the  other  transverse.  A  combination  of  these  movements 
results  in  circumduction,   but  it   has  at  least  no  voluntary  movement  of  rotation. 


334 


APPLIED  ANATOMY. 


When  rotation  of  the  hand  occurs  it  is  accompHshed  by  pronating  or  supinating- 
the  forearm.  If  the  wrist-joint  posssssed  this  latter  movement  it  would  be  a  ball- 
and-socket  or  enarthrodial  joint.  The  hand  can  be  flexed  and  extended  through  an 
arc  of  approximately  140  degrees  and  adducted  and  abducted  about  half  as  much. 
The  position  assumed  by  the  bones  in  flexion  and  extension  is  shown  in  Figs.  343 
and  344. 

.    Adduction  or  bending  toward  the  ulnar  side  is  much  greater  than  is  possible 
toward  the  radial  side.     The  fact  of   the  ulna    not  coming  so   low  as  the  radius 


Scaphoid       /      /  / 

Trapezium    /  Second  metacarpal 

Trapezoid 

Fig.  343. — Position  assumed  by  the  carpal  bones  in  flexion  of  the  wrist. 

accounts,  at  least  in  part,  for  this.  The  lateral  ligaments  check  the  movements  of 
abduction  and  adduction,  and  in  addition  the  contact  of  the  styloid  process  of  the 
radius  with  the  trapezium  prevents  further  outward  movement. 

The  extent  of  the  movements  of  the  wrist  of  course  varies  much  in  different 
individuals.  The  laxness  of  the  joints  in  children,  women,  and  those  not  accustomed 
to  hard  manual  labor  is  well  known. 

The  movements  of  the  wrist  are  performed  by  two  different  sets  of  muscles. 


Trapezoid 


Trapezium 


Second  metacarpal 
Fig.  344. — Position  assumed  by  the  carpal  bones  in  extension  of  the  wrist. 

One  set  comprises  the  flexors  and  extensors  of  the  carpus  and  the  other  the  flexors 
and  extensors  of  the  thumb  and  fingers. 

The  first  set  is  composed  of  the  flexor  carpi  radialis  and  flexor  carpi  ichiaris, 
with,  which  we  may  perhaps  include  the  palmaris  longus, — although  it  properly 
belongs  with  the  finger  muscles, — and  of  the  extensor  carpi  tibiaris,  exteyisor  carpi 
radialis  h?igior,  and  extensor  carpi  radialis  brevior.  If  the  fingers  are  clinched 
and  the  extensors  of  the  fingers  contract  they  aid  the  three  carpal  extensors  to  bend 
the  hand  backward.  If  the  fingers  are  held  extended  and  the  flexors  of  the  fingers 
contract  they  aid  the  carpal  flexors  to  bend  the  hand  forward.      Contraction  of  the 


REGION  OF  THE  WRIST.  335 

flexor  and  extensor  carpi  ulnaris  adducts  the  hand  and  contraction  of  the  flexor  carpi 
radiahs  and  extensor  carpi  radiahs  longior  and  brevdor,  aided  by  the  short  extensor 
of  the  thumb  and  extensor  ossis  metacarpi  poUicis,  abducts  the  hand. 

In  the  affection  known  as  wrist-drop  all  the  extensor  muscles  are  paralyzed.  It  is 
due  to  injury,  usually  from  pressure  on  the  radial  (musculospiral)  nerve,  either  in  the 
groove  of  the  humerus  or  in  the  axilla.  Although  there  are  a  number  of  synovial 
bursse  around  the  joint  in  connection  with  the  tendons  none  communicate  with  it. 

Muscles.  —  The  flexor  tendons  cover  the  wrist  anteriorly  and  the  extensors 
posteriorly.  With  the  flexor  group  we  may  consider  the  pronator  quadratus.  A 
third  or  radial  group  comprises  the  extensor  carpi  radialis  longior  and  brevior  and 
the  brachioradialis. 

Anteriorly. — The  tendons  on  the  front  of  the  wrist  occupy  four  different  planes 
or  levels.  The  most  superficial  layer  embraces  the  flexor  carpi  radialis,  the  palmaris 
longus,  and  the  flexor  carpi  ulnaris.  Of  these  three  the  palmaris  longus  is  the 
nearest  to  the  skin  as  it  inserts  in  the  palmar  fascia  in  front  of  the  annular  ligament. 
The  flexor  carpi  radialis  slips  under  the  upper  portion  of  the  annular  ligament  to 
insert  into  the  base  of  the  second  metacarpal  bone.     The  flexor  carpi  ulnaris  inserts 

Flexor  carpi  ulnaris  tendon 
Deep  layer  of  the  deep  fascia 

Superficial  layer  of  the  deep  fascia      /   /    ulnar  artery 
Anterior  annular  ligament    /      /  /      /     Ulnar  nerve 


_^.*»Qk,S^'**'' 


Median  nerve 
Flexor  sublimis  tendons 


Tendon  of  palmaris  longus    /      /      /    Radial  artery 

Superficial  layer  of  deep  fascia  /     Styloid  process  of  radius 

Flexor  carpi  radialis 

Fig.  345.  —  Dissection  showing  the  fascias  of  the  anterior  portion  of  the  wrist.  The  superficial  layer  is 
continuous  with  the  palmaris  longus  muscle  and  palmar  fascia;  the  deep  layer  is  continuous  with  the  anterior 
annular  ligament. 

into  the  pisiform  bone  and  continues  onward  to  the  base  of  the  fifth  metacarpal  bone 
and  the  unciform  process  of  the  unciform  bone. 

The  second  layer  of  tendons  is  composed  of  the  four  tendons  of  the  flexor  sub- 
limis digitorum.  They  fill  the  space  between  the  palmaris  longus  and  the  flexor 
carpi  ulnaris. 

The  third  layer  is  composed  of  the  four  tendons  of  the  flexor  profundus  digito- 
rum toward  the  ulnar  side  and  the  flexor  longus  poUicis  toward  the  radial  side. 

The  fourth  and  last  layer  is  formed  by  the  pronator  quadratus.  This  lies  directly 
on  the  bones  and  covers  their  lower  fourth. 

It  is  sometimes  necessary  to  divide  these  tendons  in  cases  of  contraction  of  the 
wrist,  hence  the  desirability  of  being  able  to  recognize  and  locate  them. 

The  Deep  Fascia  and  Anterior  Annular  Ligament. — The  deep  fascia  cov- 
ering the  anterior  muscles  of  the  forearm  is  comparatively  thin.  As  it  approaches  the 
wrist  it  divides  into  two  layers.  The  superficial  layer  is  thin  and  runs  over  the 
tendons  of  the  palmaris  longus  and  flexor  carpi  radialis  muscles  and  the  ulnar  artery 
and  nerve.  It  is  continuous  below  with  the  palmar  fascia.  To  the  ulnar  side  it 
passes  over  the  flexor  carpi  ulnaris  muscle  to  be  continuous  with  the  posterior  annular 
ligament.  It  is  not  attached  to  the  ulna,  but  slides  over  it  as  it  follows  the  move* 
ments  of  the  hand  in  pronation  and  supination  (Fig.  345). 


33^ 


APPLIED  ANATOMY. 


-Extensor  carpi  radialis  brevior 
-Extensor  carpi  radialis  longior 


The  deep  layer  of  the  deep  fascia  covers  the  flexor  sublimis  digitorum  and 
passes  downward  beneath  the  flexor  carpi  radialis  and  brachioradialis  muscles.  It  is 
continuous  below  with  the  anterior  annular  ligament. 

The  deep  layer  blends  with  the  superficial  layer  to  the  radial  side  of  the  flexor 
carpi  radialis,  and  then  merges  with  the  posterior  annular  ligament  to  form  the  sheath 
of  two  of  the  extensor  muscles  of  the  thumb. 

On  the  ulnar  side  the  deep  layer  passes  over  the  ulnar  artery  and  vein  and  under 
the  flexor  and  extensor  carpi  ulnaris  muscles,  forming  the  posterior  portion  of  their 

sheaths,  and  then  merges  with  the  pos- 
terior annular  ligament. 

The  anterior  a^inular  ligament  is 
attached  on  the  ulnar  side  to  the  pisi- 
form bone  and  unciform  process  of  the 
unciform  bone  and  on  the  radial  side 
to  the  trapezium  and  tuberosity  of  the 
navicular  (scaphoid). 

Over  the  anterior  annular   liga- 
ment pass  the  ulnar  artery  and  nerve, 
-Brachioradialis  (supinator  longus)   the  superficial   volar  artery,  and  the 

palmar  cutaneous  branch  of  the  median 
nerve. 

Beneath  the  annular  ligament  pass 
the  median  nerve,  the  flexor  sublimis, 
flexor  profundus,  and  flexor  longus  pol- 
licis  tendons.  These  tendons  are  em- 
braced in  two  sheaths,  one  for  the 
flexor  longus  pollicis  and  the  other  for 
the  flexors  of  the  other  four  fingers, 
the  sheath  for  the  little  finger  extend- 
ing to  the  insertion  of  the  profundus 
tendon  into  the  distal  phalanx.  The 
tendinous  sheaths  accompany  the  ten- 
dons for  a  distance  of  2.5  to  5  cm.  ( i 
to  2  in.)  above  the  annular  ligament. 
Posteriorly.  —  On  the  posterior 
surface  of  the  wrist  the  tendons  may 
be  divided  into  two  groups,  an  exten- 
sor group  and  a  radial  group.  The 
extensor  group  is  divided  into  a  super- 
ficial and  deep  set.  The  superficial  set 
is  composed  of  the  extensor  communis 
digitorum,  the  extensor  minimi  digiti 
and  the  extensor  carpi  ulnaris.  The 
deep  set  is  composed  of  the  extensor 
ossis  metacarpi  pollicis,  extensor  brevis 
pollicis,  extensor  longus  pollicis,  and  extensor  indicis.  The  radial  gro7cp,  on  the 
posterior  and  outer  surface  of  the  radius,  is  composed  of  the  extensor  carpi  radialis 
longior,  the  extensor  carpi  radialis  brevior,  and  the  brachioradialis  (Fig.  346).  The 
first  two  lie  beneath  the  deep  extensor  muscles,  thus  practically  forming  a  third  layer. 
All  the  tendons  of  the  posterior  and  radial  group  of  muscles,  with  the  exception  of 
the  brachioradialis,  pass  beneath  the  posterior  annular  ligament  into  the  hand.  The 
brachioradialis  inserts  into  the  base  of  the  styloid  process  of  the  radius. 

Posterior  Annular  Ligament. — As  the  tendons  pass  down  over  the  posterior 
surface  of  the  radius  and  ulna  they  are  bound  down  by  processes  of  the  deep  fascia 
which  form  canals  in  which  they  run.  The  deep  fascia  of  the  posterior  surface  of 
the  forearm  in  the  neighborhood  of  the  wrist  is  strong,  and  forms  the  posterior 
annular  ligament.  Its  lower  border  is  about  level  with  the  upper  border  of  the 
anterior  annular  ligament.  It  is  attached  externally  to  the  posterior  and  outer  edge 
of  the  styloid  process  of  the  radius  and  internally  to  the  posterior  surface  of  the 


-Extensor  ossis  metacarpi  pollicis 
-Extensor  brevis  pollicis 
"Styloid  process  of  radius 

•  Extensor  carpi  radialis  longior 

-  Extensor  carpi  radialis  brevior 

-  Extensor  longus  pollicis 


-I 


S 


Fig.  346. — Muscles  of  the  radial  side  of  the  wrist. 


REGION  OF  THE  WRIST. 


337 


styloid  process  of  the  ulna,  the  internal  lateral  ligament,  the  pisiform,  and  adjacent 
carpal  bones.  Beneath  this  posterior  annular  ligament  are  six  compartments.  From 
the  radial  toward  the  ulnar  side  they  are  :  (i)  One  on  the  outer  side  of  the  styloid 
process  of  the  radius  for  the  extensor  ossis  metacarpi  poUicis  and  extensor  brevis 
poUicis;  (2)  for  the  extensor  carpi  radialis  longior  and  brevior,  then  comes  the 
posterior  radial  tubercle  in  the  middle  of  the  radius,  and  passing  close  along  its  ulnar 
side  is  (3)  the  extensor  longus  pollicis.  To  the  ulnar  side  of  this  tendon  is  a  com- 
paratively broad  sheath  for  (4)  the  extensor  communis  digitorum  and  the  extensor 


Extensor  ossis  metacarpi  pollicis 
and  extensor  brevis  pollicis 

Extensor  carpi  radialis  longior 
and  extensor  carpi  radialis  brevior 


Extensor  longus  pollicis. 


Extensor  carpi  ulnaris 


Extensor  minimi  digit! 


Extensor  communis  digitorum 
and  extensor  indicis 


Fig.  347. — The  sheaths  of  the  extensor  tendons  on  the  back  of  the  wrist  distended  with  wax  to  show  their  extent. 


indicis  muscles.  In  the  interval  between  the  radius  and  ulna  lies  (5)  the  tendon  of 
the  extensor  minimi  digiti,  and  on  the  posterior  side  of  the  styloid  process  of  the  ulna 
is  (6)  the  tendon  of  the  extensor  carpi  ulnaris  (Fig.  347). 

Each  of  these  six  compartments  is  lined  with  a  separate  sheath  which  extends 
under  the  annular  ligament  from  a  centimetre  or  two  above  the  joint  to  about  the 
bases  of  the  metacarpal  bones  on  the  dorsal  surface  of  the  hand. 

The  Anatomical  SnufF-Box  (la  tabatiere  anatomique,  of  Cloquet). — 
On  the  outer  dorsal  aspect  of  the  wrist,  just  below  the  radius,  is  a  depression  particu- 
larly noticeable  when  the  thumb  is  abducted  (Fig.  351,  page  341).      It  is  triangular  in 


338 


APPLIED    ANATOMY. 


shape  with  its  base  upward.  The  styloid  process  of  the  radius  forms  its  base ; 
the  extensor  brevis  polUcis  with  the  extensor  ossis  metacarpi  polHcis  forms  its  radial 
or  outer  side,  and  the  tendon  of  the  extensor  longus  poUicis  forms  its  ulnar  or  inner 
side.  Its  floor  is  formed  by  the  navicular  (scaphoid)  and  trapezium  bones. 
Through  it,  lying  on  these  bones  and  the  external  lateral  ligament,  passes  the  radial 
artery  on  its  way  to  the  first  interosseous  space.  Superficial  to  the  artery  lies  a 
vein  and  some  fine  branches  of  the  radial  nerve.     In  ligating  the  artery  at  this  point, 


Radial  vein 
Posterior  radial  tubercle 

\        JIS  /  /  /  1/ 

Posterior  ulnar  vein 


Extensor  ossis  metacarpi  pollicis 
and  extensor  brevis  pollicis 

Extensor  carpi  radialis  longior 

Extensor  carpi  radialis  brevior 

Radial  artery  in  snuff-box" 

Extensor  longus  pollicis 

Abductor  indicis. 


Posterior  annular  ligament 


\0  \^ 


Fig.  348. — View  of  the  anatomical  snuff-box  and  the  radial  artery  passing  through  it. 

care  should  be  taken  not  to  mistake  the  vein  for  it ;  the  vein  is  near  the  skin,  the 
artery  lies  deep  on  the  lateral  ligament  and  bones  (Fig.  348). 


SURFACE   ANATOMY  OF   THE   WRIST. 

The  bellies  of  many  of  the  muscles,  mainly  the  superficial  ones,  cease  as  they 
become  tendinous  about  the  middle  of  the  forearm.  Hence  the  rapid  decrease 
in  size  as  one  descends.  When  the  wrist  is  reached  there  is  a  swelling  on  each  side 
caused  by  the  expanded  lower  end  of  the  radius  on  the  outer  side  and  the  head  of 
the  ulna  on  the  inner.  The  medial  (inner)  prominence  is  rendered  more  marked  by 
abducting  the  hand,  the  lateral  (outer)  prominence  by  adducting  it.  Just  beyond 
these  there  is  a  constriction  as  the  wrist  passes  into  the  hand. 


REGION    OF    THE    WRIST.  339 

Above  the  wrist  on  the  anterior  and  outer  part  can  be  felt  the  radius.  Its  lower 
2  or  2. 5  cm.  (i  in.)  is  sharp  and  prominent — this  is  the  anterior  border  of  the  styloid 
process.  On  the  outer  side  at  its  base  is  the  point  of  insertion  of  the  brachioradialis 
tendon.  Following  the  bone  down  on  its  outer  side,  at  the  upper  margin  of  the 
anatomical  snuff-box,  one  feels  the  tip  of  the  styloid  process,  a  most  important 
landmark. 

On  the  outer  surface  of  the  radius  beginning  below  between  the  tip  of  the  styloid 
process  and  its  sharp  anterior  border  are  the  extensor  ossis  metacarpi  pollicis  and 
extensor  brexis  pollicis  tendons.  They  can  readily  be  seen  and  felt  when  the  thumb 
is  extended  as  they  cross  obliquely  over  the  lower  end  of  the  radius.  The  sheaths 
of  these  tendons  frequently  become  inflamed  from  injuries,  causing  what  is  termed 
tenosynovitis.  If  the  hand  is  laid  on  the  lower  portion  of  the  radius  of  a  patient  so 
affected,  and  he  is  told  to  move  the  thumb,  a  characteristic  creaking  can  be  felt  as 
the  tendons  move  in  their  inflamed  sheaths. 

The  edge  of  the  articular  surface  of  the  radius  can  be  indistinctly  felt  from  the 
tip  of  the  styloid  process  to  the  edge  of  the  flexor  carpi  radialis  internally  and  across 
the  back  of  the  wrist  in  an  upwardly  curved  line  toward  the  ulna. 

On  the  inner  side  of  the  wrist  can  be  felt  and  seen  the  prominence  made  by  the 
head  of  the  ulna.  The  ulna  is  subcutaneous  and  can  be  followed  up  the  forearm 
posteriorly  its  entire  length.  It  is  not  covered  by  muscles  on  its  inner  border,  but 
on  its  anterior  surface  is  the  flexor  carpi  ulnaris  tendon  beneath  which  is  the  flexor 
profundus  digitorum,  this  latter  being  separated  from  the  bone  by  the  origin  of  the  pro- 
nator quadratus.  If  the  posterior  surface  of  the  ulna  is  followed  downward  the  styloid 
process  forming  its  extremity  can  be  distinctly  felt,  especially  if  the  hand  is  placed 
in  the  supine  position  and  slightly  flexed.  Overlying  the  head  of  the  ulna  posteriorly 
is  the  tendon  of  the  extensor  carpi  ulnaris  muscle  going  to  the  base  of  the  fifth  meta- 
carpal bone.  This  tendon  follows  the  movements  of  the  hand  in  pronation  and 
supination,  but  the  styloid  process  of  the  ulna  remains  stationary.  When  the  hand  is 
pronated  the  tendon  lies  to  the  anterior  side  of  the  styloid  process,  but  when  the  hand 
is  supinated  it  lies  toward  its  posterior  side.   This  tendon  cannot  be  readily  recognized. 

The  inner  and  posterior  surface  of  the  cuneiform  bone  can  be  felt  immediately 
below  the  head  of  the  ulna.  Some  difficulty  may  be  experienced  in  distinguishing 
one  from  the  other;  if,  however,  the  hand  is  abducted  and  adducted  the  cuneiform 
bone  can  be  felt  to  move  while  the  ulna  remains  stationary.  On  the  palmar  surface 
of  the  wrist,  immediately  below  the  ulna,  can  be  felt  the  distinct  bony  prominence 
formed  by  the  pisiform  bone.      The  flexor  carpi  ulnaris  inserts  into  it. 

About  2  to  2. 5  cm.  ( I  in. )  below  and  to  the  radial  side  of  the  pisiform  bone  is 
the  unciform  process  of  the  unciform  bone.  It  is  best  detected  by  laying  the  ball  of 
the  thumb  over  the  spot  and  making  deep  pressure  with  a  rolling  motion.  On  the 
radial  side  of  the  anterior  surface,  directly  in  line  with  the  tendon  of  the  flexor  carpi 
radialis,  is  the  prominent  tubercle  of  the  navicular  (scaphoid)  bone;  a  centimetre 
farther  on,  in  line  with  the  thumb,  is  the  ridge  of  the  trapezium.  The  anterior  annular 
ligament  is  attached  to  its  outer  surface  about  2.5  cm.  (i  in. )  below  the  styloid  proc- 
ess of  the  radius  ;  a  bony  prominence  formed  by  the  trapezium  marks  its  junction 
with  the  metacarpal  bone  of  the  thumb  in  front. 

The  ability  to  locate  the  carpometacarpal  joint  of  the  thumb  is  of  importance 
in  reference  to  the  diagnosis  of  fractures  and  other  injuries.  On  comparing  the  two 
styloid  processes  it  will  be  seen  that  the  styloid  process  of  the  radius  extends  i  cm. 
(fin.)  lower  than  that  of  the  ulna.  This  is  best  observed  with  the  hand  in  a  prone 
position.  Across  the  front  of  the  wrist  there  are  two  transverse  lines.  The  proxi- 
mal or  upper  one  corresponds  with  the  radiocarpal  joint  or  wrist-joint.  The  distal  or 
lower  one  corresponds  with  the  joint  between  the  two  rows  of  carpal  bones  and 
marks  the  upper  edge  of  the  anterior  annular  ligament. 

On  the  posterior  surface  of  the  wrist,  one-third  of  the  width  of  the  wrist  across 
from  the  edge  of  the  radius,  can  be  felt  a  bony  prominence.  It  is  the  posterior  radial 
tubercle.  If  the  thumb  is  extended  the  tendon  of  the  extensor  longus  polhcis  leads 
directly  to  the  tubercle  and  lies  along  its  ulnar  border.  This  tubercle  marks  the  middle 
of  the  posterior  surface  of  the  radius.  The  radius  passes  two-thirds  across  the  wrist 
and  the  ulna  the  other  third ;  by  firm  pressure  the  interval  between  them  can  be  felt. 


340 


APPLIED    ANATOMY. 


If  the  hand  is  firmly  clenched  and  flexed  on  the  forearm  the  tendons  on  the 
anterior  surface  of  the  wrist  become  prominent.  The  most  evident  is  the  palmaris 
longus  which,  though  sometimes  absent,   usually  stands  out  clear  and  sharp.      Lying 


Line  indicating  the  joint 

between  the  first  and  second 

row  of  carpal  bones 

Pisiform  bone 

Line  indicating  the 
radiocarpal  joint 


Flexor  carpi  ulnaris  muscle 
Ulnar  artery  and  nerve 


Styloid  process  of  radius 

Groove  for  radial  artery 

Swelling  formed  by  the 
extensors  of  the  thumb 

Flexor  carpi  radialis 

Palmaris  longus 

Median  nerve 


Fig.  349. — Surface  anatomy  of  anterior  surface  of  wrist. 


Tuberosity  of 
the  scaphoid 


Flexor  carpi  radialis 

Styloid  process  of  radius 

Palmaris  longus 


Pisiform  bone 
Prominence  formed 
by  the  flexor  sublimis 
digitorum 
Flexor  carpi 
ulnaris  muscle 


Fig.  350. — Surface  anatomy  of  the  anterior  portion  of  the  wrist. 

along  its  radial  border  is  the  tendon  of  the  flexor  carpi  radialis;  between  the  two  on 
a  lower  level  lies  the  median  nerve.  In  front  of  the  ulna,  and  going  directly  down- 
ward to  the  pisiform  bone,  is  the  tendon  of  flexor  carpi  ulnaris  (Fig.  349). 


REGION   OF   THE   WRIST. 


341 


If  the  hand  is  extended  the  tendon  of  the  flexor  carpi  ulnaris  stands  out  clearly. 
In  the  hollow  to  its  lateral  (outer)  side  lie  the  ulnar  nerve  and  artery.  A  rounded 
muscular  swell  fills  the  space  between  the  ulnar  artery  and  the  tendon  of  the  palmaris 
longus, — it  is  caused  by  the  flexor  sublimis  digitorum  (see  Fig.  350).  It  is  here 
that  abscesses  show  when  they  travel  up  from  the  hand. 

Between  the  outer  edge  of  the  flexor  carpi  radialis  tendon  and  the  anterior  outer 
edge  of  the  radius  is  a  groove  in  which  runs  the  radial  artery.  The  position  of  the 
extensor  ossis  metacarpi  poUicis  and  extensor  brevis  pollicis  which  run  together  over 
the  outer  surface  of  the  radius  can  best  be  determined  by  abducting  the  thumb  and 
so  making  these  tendons  prominent  (Fig  351). 


Extensor  longus  pollicis 

Extensor  brevis  pollicis 

and  extensor  ossis  metacarpi 

pollicis 

Anatomical  snuff-box 

Tip  of  styloid  process  of 
radius 


Fig.  351. — Surface  anatomy  of  the  outer  dorsal  portion  of  the  wrist,  showing  the  anatomical  snuff-box. 


In  the  same  manner  the  extensor  longus  pollicis  tendon  can  be  made  prominent 
and  followed  to  the  posterior  radial  tubercle.  By  firm  pressure  the  upper  limits  of 
the  first  and  second  interosseous  spaces  can  be  felt.  They  mark  the  bases  of  the 
metacarpal  bones.  The  extensor  carpi  radialis  longior  passes  across  the  snuff-box  to 
insert  into  the  radial  side  of  the  base  of  the  second  metacarpal  bone.  The  radial 
artery  as  it  dips  down  between  the  first  and  second  metacarpal  bones  lies  just  to 
its  outer  side.  Crossing  under  the  tendon  of  the  extensor  longus  pollicis  is  the 
extensor  carpi  radialis  brevior,  which  proceeds  to  the  top  of  the  second  interosseous 
space  to  insert  into  the  adjoining  sides  of  the  second  and  third  metacarpal  bones. 

In  the  chink  between  the  radius  and  ulna  lies  the  tendon  of  the  extensor 
minimi  digiti.    Between  this  tendon  and  the  radial  tubercle  are  the  four  tendons  of  the 


342 


APPLIED  ANATOMY. 


extensor  communis  digitorum  and  extensor  indicis  muscles.  Passing  over  the  head 
of  the  ulna  to  insert  into  the  base  of  the  fifth  metacarpal  bone  is  the  tendon  of  the 
extensor  carpi  ulnaris.  It  is  best  felt  just  beyond  the  extremity  of  the  ulna  when  the 
hand  is  drawn  toward  the  ulnar  side.  It  inserts  into  the  base  of  the  fifth  metacarpal 
bone. 

Compound  Ganglion. — Large  effusions  into  the  sheath  of  the  fiexor  tendons 
of  the  wrist,  usually  purulent  or  tuberculous  in  character,  sometimes  cause  two  swell- 


.'^ 


Fig.  352. — Compound  ganglion  showing  swellings  above  and  below  the  anterior  annular  ligament.    (From  author's 

sketch  of  a  tuberculous  case.) 

ings,  one  in  the  palm  of  the  hand  and  the  other  above  the  wrist.  These  commu- 
nicate beneath  the  anterior  annular  ligament  and  form  what  is  called  a  compound 
ganglion  (Fig.  352). 

FRACTURES  OF  THE  LOWER  END  OF  THE  RADIUS  AND  ULNA. 

The  lower  end  of  the  ulna  is  rarely  fractured,  but  that  of  the  radius  vies  with 
fracture  of  the  clavicle  in  being  the  most  frequent  of  all  fractures. 


I 


Fig.  3 S3. — Colles's  fracture  of  the  lower  end  of  the  radius,  showing  the  "  silver  fork  deformity"  and  displacement 

of  the  fragments. 

Colles's  Fracture. 

Fractures  of  the  radius  which  occur  at  the  wrist  possess  certain  distinct  charac- 
teristics and  were  for  a  long  time  confounded  with  dislocations  of  the  wrist.  These 
fractures  are  generally  grouped  by  modern  surgeons  under  the  name  of  Colics' s 
fracture.  This  fracture  was  first  correctly  described,  according  to  both  Hamilton 
and  Stimson,  by  Pouteau  ("CEuvres  Posthumes,"  t.  11,  p.  251,  1783;  also  Nelaton, 
"  Chirurgie  Path.,"  t.  i,  p.  739).  Mr.  Colles,  a  Dublin  surgeon,  described  the 
injury  most  carefully  in  the  Edinburgh  Medical  and  Surgical  Jouryial,  April,  18 14, 
but  it  is  largely  due  to  Robt.  W.  Smith's  "Treatise  on  Fractures  in  the  Vicinity 


REGION   OF   THE   WRIST.  343 

of  Joints,"  Dublin,  1847,  that  the  name  CoUes's  fracture  has  become  generally 
accepted.  Mr.  CoUes  placed  the  injury  i]4  inches  (about  4  cm.)  above  the  joint. 
Mr.  Smith  placed  it  from  }^  in.  to  i  in.  (6  to  25  mm.)  above  the  joint.  Most  recent 
waiters  include  all  fractures  within  4  cm.  ( I  ^  in. )  of  the  lower  edge  of  the  radius 
under  this  name,  though  some  few  go  still  higher.  When  the  line  of  fracture  lies 
more  than  4  cm.  above  the  joint  it  loses  the  characteristics  of  a  Colics' s  fracture  and 
partakes  of  those  of  fractures  of  the  shaft ;  hence  we  will  not  go  beyond  that  limit. 

The  line  of  fracture  is  most  commonly  found,  as  stated  by  Robt.  W.  Smith, 
from  6  to  25  mm.  (^  to  i  in.)  above  the  joint.  It  passes  almost  transversely 
across  the  bone  or  inclines  slightly  downward  to  the  ulnar  side.  It  also  lies  nearer 
the  joint  on  the  anterior  surface  and  inclines  backward  and  upward  toward  the  elbow. 
Hence  the  direction  is  from  above  downward  and  forward  (Fig.  353). 

It  is  produced  while  the  hand  is  extended  (dorsally  flexed)  either  by  direct 
transmission  of  the  force  from  the  palmar  surface  of  the  wrist  or  by  tension  of  the 
anterior  radiocarpal  ligament. 

The  lower  fragment  is  displaced  upward  and  backward  on  the  shaft  of  the 
radius.  This  causes  it  to  be  tilted  backward  so  that  the  articular  surface  is  rotated 
on  a  transverse  axis  more  in  the  direction  of  the  dorsum  than  normal  and  the  hand  is 
also  carried  toward  the  radial  side.  The  dorsal  displacement  is  due  to  the  direction 
of  the  violence  and  not  to  muscular  action.  The  radial  side  of  the  fragment  is 
displaced  upward  more  than  the  ulnar  because  the  triangular  fibrocartilage  retains  its 


cy^ 


Fig.  354. — Colles's  fracture  of  the  radius,  showing  inclination  of  hand  toward  the  radial  side  and  prominence  of 
the  styloid  process  of  the  ulna.     (From  author's  sketch.) 

radio-ulnar  attachments.  This  prevents  the  ulnar  side  from  rising,  while  the  radial 
side  is  pulled  up  by  the  radial  flexor  and  extensor  muscles.  If  the  fracture  is  not 
extremely  close  to  the  joint  the  brachioradialis  will  pull  the  lower  fragment  toward 
the  radial  side  and  up  toward  the  elbow. 

As  the  hand  is  attached  to  the  radius  it  follows  the  lower  fragment ;  the  extensor 
muscles  of  the  thumb,  the  flexor  carpi  radialis,  and  the  two  extensor  carpi  radialis 
muscles  all  tend  to  aid  the  brachioradialis  in  producing  the  displacement  toward 
the  radial  side  (Fig.  354). 

The  lower  fragment  is  displaced  toward  the  dorsum  and  the  upper  fragment 
toward  the  palmar  surface.  This  produces  the  ' '  silver  fork  deformity' '  of 
Velpeau.  This  dorsal  projection  is  sometimes  increased  by  the  presence  of  the 
"carpal  tumor,"  a  swelling  due  to  effusion  almost  directly  above  the  joint.  The 
projection  of  the  upper  fragment  toward  the  palmar  surface  and  the  effusion  in  the 
sheaths  of  the  flexor  tendons  cause  a  protrusion  on  the  anterior  surface  of  the  wrist 
and  a  marked  increase  in  the  lower  anterior  radiocarpal  crease. 

To  reduce  the  deformity  the  upper  fragment  is  firmly  grasped  with  one  hand 
while  with  the  other  the  hand  of  the  patient  is  forcibly  adducted  (toward  the  ulnar 
side)  and  then  sharply  flexed.  This  drags  the  distal  fragment  down  and  forward  off 
of  the  proximal  one.  To  retain  the  fragments  in  position  some  surgeons  use  a  pistol- 
shaped  splint  to  hold  the  hand  turned  toward  the  ulnar  side  and  place  a  graduated 
compress  on  the  palmar  surface  with  its  base  opposite  the  line  of  fracture  and  its 
apex  upward  and  another  pad  on  the  dorsal  surface  with  its  apex  downward  over  the 
hand.     Other  surgeons  place  the  hand  in  a  flexed  position,  allowing  it  to  hang. 


344 


APPLIED   ANATOMY. 


Separation  of  the  Lower  Epiphysis  of  the  Radius, 

The  lower  radial  epiphysis  fuses  with  the  shaft  at  about  the  twentieth  year ; 
therefore  epiphyseal  separation  can  occur  up  to  that  time.      The  epiphyseal  line 

passes  across  the  bone  from  the  base  of  the  styloid  process 
to  the  upper  edge  of  the  radio-ulnar  joint  (Fig.  355). 

The  displacement,  symptoms  and  treatment  are  the  same 
as  in  CoUes's  fracture  and  it  is  quite  possible  that  many  cases 
diagnosed  as  Colles's  fracture  may  be  epiphyseal  separations. 

Fracture  of  the  Lower  End  of  the  Radius  with 
Displacement  Forward. 

This  fracture,  though  rare,  occasionally  occurs,  and  if 
union  has  taken  place  the  deformity  is  marked  and  the 
injury  is  liable  to  be  diagnosed  as  a  luxation.  It  has  been 
particularly  described  by  Dr.  John  B.  Roberts  ("A  Clinical, 
Pathological,  and  Experimental  Study  of  Fracture  of  the 
Lower  End  of  the  Radius  with  Displacement  of  the  Carpal 
Fragment  toward  the  Flexor  or  Anterior  Surface  of  the 
Wrist, ' '  Phila. ,  1 897  ) .  On  account  of  the  difificulties  in  diag- 
nosis it  is  well  to  examine  its  anatomical  peculiarities. 

Displacement. — The  lower  fragment  is  tilted  forward 
toward  the  palmar  surface  of  the  wrist,  carrying  the  radial 
side  of  the  hand  with  it  (Fig.  356). 

Signs. — The  line  of  the  radius  can  be  followed  and 
felt  to  curve  at  its  lower  portion  toward  the  palmar  surface. 
The  hand  descending  with  the  displaced  fragment  causes  a 
groove  to  appear  across  the  dorsum  from  one  styloid  process  to  the  other.  The 
dorsal  surface  of  the  lower  part  of  the  forearm  is  on  a  higher  plane  than  that  of  the 
carpus.     As  the  hand  is  lower  than  normal  this  causes  the  lower  end  of  the  ulna  to 


Fig.  355. — Epiphyses  of  the 
lower  ends  of  the  radius  and 
ulna;  union  occurs  with  the 
shaft  of  the  bones  at  about  the 
20th  year. 


Fig  .  3  s  6 . — Fracture  of  the  lower  end  of  the  radius  with  displacement  of  the  lower  fragment  toward  the  palmar 
surface.     (Sketch,  by  the  author,  of  a  specimen  in  the  Mutter  Museum  of  the  Philadelphia  College  of  Physicians.) 

project  much  higher  than  it  should.  On  account  of  the  tension  of  the  extensor  carpi 
radialis  longior  and  brevior  the  hand  is  held  level  with  the  forearm  and  does  not 
droop  as  in  Colles's  fracture.  Displacement  to  the  radial  side  may  or  may  not  be 
marked. 

Fracture  of  the  Lower  end  of  the  Ulna. 

Previous  to  the  use  of  the  X-rays  for  diagnostic  purposes,  fracture  of  the  lower 
end  of  the  ulna  was  considered  extremely  rare.  Fractures  of  the  ulna  above  the 
head  resemble  practically  those  of  the  shaft. 

Fracture  of  the  styloid  process  was  observed  by  D.  H.  Agnew  in  one  case  which 
was  followed  by  deformity.  Inasmuch  as  the  deep  fascia  slides  over  the  ulna  it 
is  readily  seen  that  if  it  is  perforated  one  or  other  of  the  fragments  may  be  caught  in 
the  rent.  This  is  probably  the  explanation  of  the  deformity  which  occurred  in 
Agnew' s  case.  He  advised  treatment  with  the  hand  bent  toward  the  ulnar  side  to 
relax  the  extensor  carpi  ulnaris  tendon.  Fracture  of  the  styloid  process  of  the  ulna 
has  been  shown  by  the  X-rays  to  be  a  more  frequent  accompaniment  of  Colles's 
fracture  than  was  formerly  thought  to  be  the  case, — it  tends  to  favor  displacement 
of  the  hand  toward  the  radial  side. 


RECxION   OF   THE   WRIST. 


345 


DISLOCATIONS    AT   THE  WRIST. 

The  dislocations  at  the  wrist  may  be  due  to  traumatism  or  may  occur  spontane- 
ously. There  may  be  either  a  displacement  of  the  carpus  at  the  radiocarpal  joint 
or  of  the  ulna  at  the  inferior  radio-ulnar  articulation.     These  luxations  are  very  rare. 


DISLOCATIONS  AT  THE   RADIOCARPAL  JOINT. 

It  is  to  Dupuytren  that  we  owe  the  recognition  of  the  fact  that  what  were 
previously  regarded  as  luxations  of  the  wrist  were  really  cases  of  fracture,  usually 
of  the  radius.  True  luxations  are  exceedingly  rare ;  they  may  be  either  backward 
or  forward  and  are  often  compound.  They  are  usually  the  result  of  great  violence 
and  the  ends  of  the  radius  and  ulna  in  many  cases  protrude  on  the  palmar  or  dorsal 
surface. 

Backward  luxation  is  the  more  common  of  the  two.  The  question  of  diagnosis 
is  most  important  in  relation  to  this  injury.  Many  cases  which  have  been  diagnosed 
as  luxations  afterwards  prove  to  be  fractures.  In  backward  luxation  the  deformity 
resembles  that  of  CoUes's  fracture,  with  the  following  differences  :  the  palmar  swelling 
in  dislocation  extends  farther  down  toward  the  hand  than  is  the  case  in  CoUes's 
fracture, — this  is  owing  to  the  displacement  occurring  at  the  joint  instead  of  some 
distance  above,  as  in  fracture  ;  in 
luxation  the  protrusion  forming  the 
hump  on  the  dorsal  surface  has  an 
abrupt  upper  edge  which  is  lack- 
ing in  cases  of  fracture,  and  both 
styloid  processes — of  the  radius 
and  the  ulna — remain  attached  to 
the  shaft  of  the  bones. 

Anterior  luxation  may  occur 
from  injury,  but  more  commonly  it 
is  seen  in  the  form  of  a  subluxa- 
tion which  occurs  slowly  and  spon- 
taneously usually  between  the  ages 
of  1 6  and  25  years.  It  was  first 
described  by  Dupuytren  and  later 

by  Madelung.  The  ulna  projects  markedly  toward  the  dorsal  surface  while  the 
radius  is  somewhat  less  prominent;  there  is  a  marked  hollow  on  the  palmar  surface 
of  the  forearm  just  above  the  hand.  Fig.  357,  from  a  girl  18  years  of  age,  shows 
these  points  clearly. 

DISLOCATION  OF  THE  ULNA  AT  THE  LOWER  RADIO-ULNAR  JOINT. 

The  ulna  may  be  dislocated  forwards  or  backwards.  When  associated  with 
fracture  of  the  radius  it  is  not  so  rare,  but  otherwise  it  is  seldom  seen.  Posterior  lux- 
ation is  the  most  common.  The  internal  lateral  ligament  and  triangular  cartilage 
both  usually  remain  attached  to  the  lower  end  of  the  ulna,  which  projects  markedly 
on  the  dorsal  surface.  The  injury  has  been  produced  by  falls  on  the  hand  and  forced 
pronation. 

In  recent  cases  reduction  can  usually  be  accomplished  by  direct  pressure  and 
rotation  of  the  hand,  with  traction.  The  secret  of  success  in  the  diagnosis  of  these 
obscure  fractures  and  luxations  in  the  region  of  the  wrist  lies  in  knowing  the  surface 
anatomy  and  in  being  able  to  recognize  the  various  deeper  structures  by  the  sense 
of  touch. 

EXCISION    OF   THE   WRIST. 

Formal  excisions  of  the  wrist  are  undertaken  for  tuberculous  disease.  It  is 
desirable  that  all  the  affected  tissues  be  removed.  To  do  this  is  difficult,  on  account 
of  the  number  and  extent  of  the  various  carpal  bones  and  joints  as  well  as  the 
danger  of  injuring  the  important  arteries,  nerves,  and  tendons  by  which  they  are 


Fig.  357. — Subluxation  of  the  wrist  from  disease. 


346 


APPLIED  ANATOMY. 


surrounded.  To  remove  the  diseased  parts  without  inflicting  avoidable  injury 
requires  an  exact  and  skilful  operator  who  has  a  precise  knowledge  of  the  anatomy 
of  the  region.  Interference  with  the  sheaths  of  the  tendons  will  result  in  stiffness 
and  loss  of  control  and  power  in  the  hand. 

Maisonneuve,  Boeckel,  and  Langenbeck  operated  through  a  single  dorsal  in- 
cision along  the  radial  side  of  the  extensor  indicis  tendon.  As  this  incision  was 
found  to  give  insufficient  room,  Lister,  in  1865,  advised  an  additional  incision  along 
the  ulnar  border.     Oilier,  of  Lyons,  modified  Lister's  radial  incision  by  carrying  it 


Fig.  3s8. — Excision  of  wrist,  showing  structures  involved  and  Ollier's  incisions.     The  solid  line  indicates  the  dorsal 
radial  incision  and  the  dotted  line  the  palmar  ulnar  incision. 


nearer  the  extensor  indicis  tendon  to  better  avoid  injuring  the  radial  artery  and  the 
insertion  of  the  extensor  carpi  radialis  brevior  tendon.  Oilier  also  carried  his  incision 
somewhat  higher  on  the  wrist  and  raised  the  tissues  with  a  perio'steal  elevator,  and 
divided  no  tendons. 

Ollier's  Operation. — Radial  Incision. — From  a  point  on  the  dorsum  of  the 
wrist  midway  between  the  styloid  processes,  downward  and  outward  alongside  of 
the  extensor  indicis  tendon  to  the  junction  of  the  middle  and  lower  thirds  of  the 
metacarpal  bone  of  the  index  finger  (Fig.  358). 


REGION    OF   THE    WRIST.  347 

Ulnar  Incision. — From  a  point  2.5  cm.  (r  in.)  above  the  styloid  process  of 
the  ulna  toward  its  palmar  surface,  downward  to  the  base  of  the  fifth  metacarpal 
bone  (Fig.  358). 

When  making  the  radial  incision,  branches  of  the  radial  nerve  may  be  seen  in  the 
lower  part  of  the  incision  and  should  if  possible  be  avoided.  In  making  the  ulnar 
incision  a  cutaneous  branch  of  the  ulnar  nerve  should  be  avoided  as  it  verges  toward 
the  dorsal  surface  below  the  styloid  process. 

The  extensor  indicis  tendon  is  pulled  aside  and  the  extensor  carpi  radialis 
brevior  beneath  detached  with  the  periosteum  from  the  base  of  the  third  metacarpal 
bone.  The  incision  is  then  extended  higher  up  the  wrist,  care  being  taken  not  to  in- 
jure the  tendon  of  the  extensor  longus  poUicis  at  the  posterior  radial  tubercle.  The 
periosteum  is  to  be  detached  over  the  lower  end  of  the  radius,  the  radiocarpal  joint 
opened,  and  the  carpal  bones  removed  one  after  another.  The  pisiform-  bone, 
unciform  process,  and  trapezium  are  left  when  possible.  In  removing  the  unciform 
process  the  deep  branch  of  the  ulnar  nerve  should  be  avoided.  If  the  trapezium  is 
removed  care  must  be  taken  not  to  wound  the  radial  artery  as  it  goes  over  the  bone 
to  dip  between  the  first  and  second  metacarpal  bones,  and  also  to  avoid  the  flexor 
carpi  radialis  tendon  as  it  crosses  to  the  inner  side  of  the  ridge  of  the  trapezium  on 
its  palmar  surface. 

The  articular  ends  of  the  ulna  and  radius  may  be  removed  with  a  small  saw  if 
necessary.  As  Jacobson  says,  this  operation  is  a  tedious  and  difficult  one,  and  we 
might  add  that  it  is  liable  to  be  an  inefficient  one,  owing  to  the  inability  to  remove 
all  of  the  diseased  tissue. 

Operations  of  Studsgaard  and  Mynter. — Studsgaard  of  Copenhagen  in 
1891  ("  Hospitalstidenden,"  Jan.  7,  iSgi)  suggested,  and  Herman  Mynter  of  Buf- 
falo (  Transactions  of  the  American  Ortliopedic  Association,  1894,  vol.  vii,  p.  253) 
carried  out  the  method  of  splitting  the  hand  on  the  dorsum  from  the  web  between 
the  second  and  third  fingers  to  the  lower  edge  of  the  radius,  and  on  the  palmar 
surface  to  the  base  of  the  thenar  eminence. 

Dr,  Wm.  J.  Taylor  {Annals  of  Snrgery,  vol.  xxii,  1900,  p.  360)  modified  the 
operation  by  employing  only  the  dorsal  incision.  This  operation  gives  full  access 
and  exposure  to  the  parts,  and  all  disease  can  most  readily  be  recognized  and  re- 
moved with  the  scissors  or  other  instruments.  It  is  probably  the  best  method  of 
exposure  and  operation  when  simple  incision  and  curetting  does  not  suffice. 

AMPUTATION   THROUGH   THE  WRIST-JOINT. 

When  it  is  possible  to  do  so  the  interarticular  fibrocartilage  over  the  lower  end 
■of  the  ulna  is  not  to  be  interfered  with.  The  lower  radio-ulnar  joint  is  therefore  not 
injured  and  the  movements  of  pronation  and  supination  are  preserved. 

The  styloid  process  of  the  radius  is  i  cm.  below  that  of  the  ulna.  It  is  directly 
on  the  outer  side  of  the  radius,  while  the  styloid  process  of  the  ulna  is  toward  the 
posterior  surface. 

On  account  of  the  skin  of  the  palm  being  thick  and  well  adapted  for  pressure  a 
long  palmar  flap  is  preferred. 

Incision. — On  account  of  retraction,  the  knife  is  entered  i  cm.  (|  in.)  below 
the  radial  styloid  process — the  thumb  being  abducted  to  render  the  tissues  tense,  and, 
if  the  left  hand  is  being  operated  on,  the  knife  is  carried  straight  down  well  on  the 
thenar  prominence.  It  is  then  curved  abruptly  across  the  palm  on  a  level  almost  or 
quite  as  low  as  the  web  of  the  thumb.  It  is  continued  to  the  ulnar  side  and  up 
to  within  i  cm.  of  the  styloid  process  of  the  ulna.  The  flap  should  be  an  almost 
square  one  with  rounded  ends.  The  incision  goes  down  to  but  does  not  divide  the 
flexor  tendons  (Fig.  359.) 

This  flap,  embracing  the  palmar  fascia  and  part  of  the  thenar  and  hypothenar 
muscles,  is  at  once  raised  from  the  flexor  tendons,  care  being  taken  not  to  catch  the 
knife  on  the  unciform  and  pisiform  bones. 

The  hand  is  now  pronated  and  a  dorsal  flap  2.5  cm.  (i  in.)  long  is  cut.  As  the 
skin  is  loose  and  elastic  this  length  is  needed  to  provide  against  retraction. 


348 


APPLIED    ANATOMY. 


The  flaps  being  reflected  and  the  hand  flexed,  disarticulation  is  begun  by  enter- 
ing the  knife  on  the  ulnar  side  of  the  dorsum,  beneath  the  styloid  process.  The 
joint  is  followed  around  to  the  radial  side,  bearing  in  mind  that  it  curves  markedly 
upwards. 

If  the  right  hand  is  being  operated  on  and  the  knife  is  entered  transversely 
it  will  strike  the  scaphoid  bone,  therefore  it  must  be  at  once  inclined  obliquely 
upward.  Section  of  the  flexor  muscles  and  anterior  ligament  completes  the  disartic- 
ulation. The  radial  artery  will  be  cut  in  the  snufl-box.  The  ulnar  will  be  seen  on 
the  inner  side  of  the  palmar  flap,  and  on  the  outer  side  may  be  seen  the  superficial 
volar.  Some  small  branches  of  the  anterior  and  posterior  carpal  and  interosseous 
arteries  may  require  ligation. 

Some  operators  remove  the  styloid  processes  of  the  radius  and  ulna.  If  this  is 
done,  care  is  to  be  taken  not  to  go  so  high  as  to  injure  the  insertion  of  the  brachio- 
radialis  on  the  radius  and  the  attachment  of  the  triangular  cartilage  on  the  ulna. 
Usually  the  styloid  processes  are  not  interfered  with,  in  order  to  avoid  impairing  the 
movements  of  pronation  and  supination. 

Ligation  of  the  Radial  Artery  on  the  Dorsum  of  the  Hand. — The 
radial  artery  can  be  ligated  in  the  anatomical  snuff-box  as  it  crosses  the  back  of  the 


Extensor  communis  tendons 
Extensor  minimi  digiti  / 


Extensor  longus  pollicis 

Extensor  carpi  radialis  brevior 
/    Extensor  carpi  radialis  longior 


Articular  surface 
of  radius 


Radial  artery 


Ext.  carpi  ulnaris  - 
Triangular  cartilage 
Flexor  carpi  ulnaris 
Ulnar  nerve 


I'almar  flap 


Fig.  3S9 


'Inar  artery 
, — Amputation  through  the  wrist-joint  of  the  right  side. 


hand  to  dip  between  the  first  and  second  metacarpal  bones  and  the  two  heads  of  the 
abductor  indicis  muscle.  The  course  of  the  artery  is  indicated  by  a  line  drawn  from 
the  tip  of  the  styloid  process  of  the  radius  to  the  upper  end  of  the  first  interosseous 
space  (see  Fig.  348,  p.  338). 

The  incision  is  usually  made  in  the  direction  of  the  tendons  from  the  styloid 
process  down.  As  soon  as  the  skin  is  divided  there  may  be  exposed  in  the  super- 
ficial fascia  some  branches  of  the  radial  nerve  and  the  radial  vein.  These  being 
pushed  aside,  the  deep  fascia  is  opened  and  the  artery  found  with  its  two  companion 
veins  lying  deep  down  on  the  external  lateral  ligament  and  trapezium.  The  most 
common  error  in  this  operation  is  mistaking  the  superficial  vein  for  the  artery  and 
not  searching  deep  enough. 

If  the  radial  artery  is  wounded  as  it  passes  through  the  snuff-box  bleeding  will 
be  very  free.  It  is  almost  impossible  to  ligate  the  divided  ends  in  the  wound  be- 
cause the  proximal  end  retracts  under  the  short  extensor  tendons  of  the  thumb  and 
the  distal  end  retracts  through  the  first  interosseous  space  deep  into  the  palm  of  the 
hand  so  that  they  cannot  be  reached.  When  such  is  the  case  it  is  necessary  either 
to  ligate  the  ulnar  and  radial  arteries  on  the  anterior  surface  just  above  the  wrist  or, 
as  we  did  in  one  case,  pack  the  wound  with  antiseptic  gauze  and  keep  the  hand  well 
elevated. 


THE   HAND. 


349 


THE  HAND. 

As  has  already  been  stated,  the  hand  is  the  essential  part  of  the  upper  extremity, 
and  mobility  is  its' main  characteristic.  It  terminates  in  five  digits  which  possess  a 
bony  support  or  framework.  In  order  that  the  fingers  may  perform  their  many  com- 
plicated movements  numerous  joints  are  inserted  which  necessitate  a  still  greater 
number  of  bones.  The  movements  of  the  hand  and  fingers  are  accomplished  not 
only  by  the  long  flexors  and  extensors  of  the  fingers  and  the  flexors  and  extensors 


Ulna 
lexor  carpi  ulnaris 

Styloid  process 
Semilunar 
Cuneiform 
Pisiform 


]^^0s  magnum 
Unciform 
[Unciform  process 
'lexer  carpi  ulnaris 


Pig.  360. — Anterior  view  of  the  bones  of  the  carpus  and  metacarpus,  showing  insertion  of  the  two  carpal  flexoi 

muscles. 

of  the  carpus,  which,  as  has  already  been  shown,  come  down  from  the  forearm,  but 
in  addition  by  numerous  short  muscles  situated  in  the  hand  itself.  An  especial 
peculiarity  of  the  human  hand  is  the  ability  to  oppose  the  thumb  to  the  other  digits. 


BONES   OF  THE   HAND. 

The  carpus  contains  8  bones,  the  metacarpus  5,  the  phalanges  14;  27  bones  in  all. 

The  Carpal  Bones. — The  carpal  bones  are  in  two  rows.  The  upper  row  is 
convex  above  and  the  lower  row  is  convex  below. 

The  upper  row,  beginning  on  the  radial  side,  is  composed  of  the  navicular 
{scaphoid) ,  lunate,  cuneiform,  and  pisiform.  The  three  first-named  articulate  with 
the  radius  and  triangular  cartilage,  forming  the  radiocarpal  joint,  but  the  pisiform 
is  separate.      It  is  perched  on  the  cuneiform  bone  and  is  practically  a  sesamoid  bone 


3  so 


APPLIED   ANATOMY. 


developed  in  the  tendon  of  the  flexor  carpi  ulnaris  muscle.  The  anterior  end  of  the 
navicular  (scaphoid)  has  on  its  palmar  surface  a  tuberosity  which  can  be  felt  immedi- 
ately below  the  flexor  carpi  radialis  tendon  at  the  wrist  ;  this  tendon  passes  along  the 
palmar  surface  to  insert  in  the  base  of  the  second  metacarpal  bone  (Fig.  360). 

The  lower  row,  beginning  on  the  radial  side,  is  composed  of  the  trapezium, 
trapezoid,  os  magnum,  and  tinciform.  The  first  three  articulate  with  the  first  three 
m.etacapal  bones  but  the  unciform,  like  the  cuboid  in  the  foot,  articulates  with  two 
metacarpal  bones — the  fourth  and  fifth. 

The  trapezium  articulates  with  the  first  metacarpal  bone  by  a  saddle-shaped  joint 
and  has  on  its  palmar  surface  a  ridge.      Along  the  inner  side  of  this  ridge  runs  the 


Radius 
Posterior  radial  or  thecal  tubercle 

Styloid  process  of  radius 

Scaphoid 

Trapezium 

Trapezoid 

Radial  arteryj 

Metacarpal  bone  of  the  thumb 


Extensor  carpi 
radialis  longior 


Extensor  carpi 
radialis  brevier 


Ulna 


Head  of  ulna 

■Styloid  process  of  ulna 
Semilunar 

Cuneiform 

Extensor  carpi  ulnaris 
Os  magnum 
Unciform 


Fig.  361. — Posterior  view  of  the  bones  of  the  carpus  and  metacarpus,  showing  the  insertion  of  the  three  carpal 

extensor  muscles. 

flexor  carpi  radialis  tendon.  The  ridge  of  the  trapezium  and  tuberosity  of  the  navicu- 
lar (scaphoid)  give  attachment  to  the  radial  side  of  the  aiiterior  annular  ligament. 

The  unciform  bone  has  a  hook-like  (unciform)  process  on  its  palmar  surface.  It 
can  be  felt  by  deep  pressure  2  cm.  (about  ^  in. )  below  and  to  the  radial  side  of  the 
pisiform  bone.  This  process  and  the  pisiform  bone  give  attachment  to  the  ulnar  side 
of  the  anterior  annular  ligament. 

The  Metacarpal  Bones. — The  metacarpal  bones  have  their  bases  at  the 
carpus  and  their  heads  toward  the  phalanges.  The  shafts  are  small  as  compared  with 
the  extremities,  and  hence  are  not  infrequently  fractured.  On  each  side  of  the  head 
is  a  small  projecting  tubercle,  which,  when  the  bone  becomes  luxated,  catches  in  the 
tissues  and  hinders  reduction. 

On  the  palmar  surface  of  the  base  of  the  second  metacarpal  bone  is  inserted  the 
flexor  carpi  radialis  and  into  the  base  of  the  fifth  the  flexor  carpi  nlnaris,  which  is 
continued  onward  from  the  pisiform  bone.     On  the  dorsal  surface,  into  the  base  of  the 


THE    HAND. 


351 


second,  is  inserted  the  extensor  cai-pi  radialis  longior;  into  the  base  of  the  third  (and 
part  of  the  second)  is  inserted  the  extensor  carpi  radialis  brevior,  and  into  the  base  of 
the  fifth,  the  exte?isor  carpi  idnaris  (Fig.  361). 

Thus  it  will  be  seen  that  all  the  flexors  and  extensors  of  the  wrist  have  their 
ultimate  insertion  into  the  metacarpal  bones. 

The  metacarpal  bone  of  the  thumb  has  inserting  into  its  base  the  extensor  ossis 
metacarpi pollicis  tendon.     As  this  tendon  has  its  origin  in  the  forearm  it  also  acts  as 


Flexor  profundus  digitorum 


Flexor  sublimis 
digitorum 


Fig.  362. — Palmar  view  of  the  flexor  tendons  of  the  finger,  showing  the  insertion  of  the  flexor  sublimis  into  the 
middle  phalanx  and  the  flexor  profundus  into  the  distal  phalanx. 

a  carpal  extensor,  but  owing  to  the  movability  of  the  thumb  it  acts  especially  as  an 
extensor  of  the  latter,  the  carpus  remaining  immovable. 

The  Phalanges. — The  thumb  has  two  phalanges  and  the  fingers  each  three. 
These  are  called  the  proximal.,  middle,  and  distal  phalanges.,  also  the  first.,  second., 
and  third  phalanges.     The  thumb  has  only  2.  proximal  and  a  distal  phalanx. 


Extensor  communis  digitorum 


Interosseous  ■ 
Lumbricalis  muscle-'^    \3!»' 


y, 


Extensor  aponeurosis 
Fig.  363. — Lateral  view  of  the  extensor  tendons  of  the  finger. 

Into  the  middle  phalanges  on  their  palmar  surfaces  are  inserted  the  fiexor  sub- 
limis digitorum  tendojis  and  into  the  distal  the  flexor  profu7idus  (Fig.  362). 
There  is  only  one  long  flexor  to  the  thumb  and  it  is  inserted  into  the  distal  phalanx. 

The  extensor  commzaiis  digitorum  opposite  the  metacarpophalangeal  joints 
sends  off  a  fibrous  expansion  which  blends  with  the  lateral  ligaments  of  the  joints 


Extensor  aponeurosis 


Extensor  communis 
digitorum 


Interosseous 
muscle 
Lumbricalis  muscle 

Fig.  364. — Dorsal  view  of  the  extensor  tendons  of  the  finger. 

(Fig.  363).  On  the  dorsum  of  the  proximal  phalanx  the  tendon  splits  into  three 
parts.  The  middle  slip  inserts  into  the  bases  of  the  middle  phalanges,  while  the  two 
lateral  slips,  after  receiving  the  insertions  of  the  lumbricales  and  part  of  the  insertions 
of  the  interossei,  insert  into  the  bases  of  the  distal  phalanges  of  the  fingers  (Fig.  364). 
The  thumb  has  two  separate  extensors,  the  extensor  brevis  pollicis  and  the  exteyisor 
longus  pollicis. 

Into  the  bases  of  the  proximal  phalanges  are  inserted  the  remaining  portion  of 
the  tendons  of  the  interossei  muscles,  which  move  the  fingers  toward  and  from  one 
another,  and  slips  from  the  palmar  fascia.     The  main  function  of  the  interossei  and 


352 


APPLIED   ANATOMY. 


lumbrical  muscles  is  to  extend  the  distal  and  middle  phalanges  and  to  flex  the  prox- 
imal ones.  When,  therefore,  most  of  them  are  paralyzed,  as  occurs  when  the  ulnar 
nerve  is  divided,  the  distal  and  middle  phalanges  are  flexed  and  the  proximal  phalan- 
ges extended,  forming  the  claw-hand  (main  griffe)  of  Duchenne. 

JOINTS    OF   THE   HAND. 

The  carpal  bones  besides  being  connected  by  short  ligaments  running  from  one 
to  another  on  their  dorsal  and  palmar  surface  also  have  their  adjacent  surfaces  con- 


Scaphoid 

Trapezoid 
Trapezium 


Os  magnum 
Unciform 


Fig.  365. — The  carpal  bones  and  joints. 

nected  by  interosseous  ligaments.  The  three  bones  of  the  first  row  are  joined  by 
two  ligaments  near  their  proximal  surfaces  which  prevent  any  communication  of  the 
radiocarpal  with  the  midcarpal  articulations.  The  four  bones  of  the  second  row  are 
joined  together  by  interosseous  ligaments  (fibrocartilages,  Morris)  which  are  not 
complete.  That  between  the  os  magnum  and  the  unciform  is  attached  more  toward 
the  palmar  surface,  while  that  between  the  os  magnum  and  trapezoid  is  more  toward 
the  dorsal  surface.  The  interosseous  ligament  between  the  trapezium  and  trapezoid 
is  usually  lacking  (Fig.  365). 

Synovial  Membrane. — From  the  above  description  it  will  be  seen  that  the 
joints  of  the  carpus  (with  the  exception  of  the  pisiform)  all  communicate  with  one 
another  and  with  the  carpometacarpal  joints,  and  that  the  synovial  membrane  is  prac- 
tically continuous  ;  hence  siippiiration  implicating  the  synovial  membrane  at  any 


THE    HAND. 


353 


point  can  travel  without  hindrance  between  all  the  carpal  (with  the  exception  of  the 
pisiform)  and  metacarpal  bones. 

The  phalangeal  joints  have  two  strong  lateral  ligaments  and  an  anterior  or 
glenoid  ligament,  but  no  posterior  ligament. 

Movements. — While  the  amount  of  motion  between  the  individual  carpal 
bones  is  limited  to  a  slight  gliding  on  one  another,  still,  when  taken  together,  a  very 
considerable  range  of  movement  is  allowed.  The  hand  can  be  fiexed  and  extended, 
abducted  and  adducted,  and  circumducted,  but  not  rotated.  If  the  bones  of  the 
forearm  at  the  wrist  are  held  immovable  it  is  impossible  to  rotate  the  hand. 

The  radiocarpal  joint  bends  more  freely  posteriorly  (extension)  than  anteriorly, 
while  the  midcarpal  bends  more  freely  in  the  opposite  direction  (Fig.  343,  344,  p. 
334),  adduction  (toward  the  ulnar  side)  is  more  extensive  than  abduction.  The 
movement  between  the  two  rows  of  carpal  bones  is  quite  extensive. 

The  movements  of  the  inner  four  carpometacarpal  joints  are  both  of  flexion  and 
extension,  mainly  toward  the  palmar  surface,  and  a  lateral  flexion  and  extension 
which  enables  a  person  to  ' '  hollow ' '  the 
hand  and  so  grasp  round  objects.  The 
palmar  flexion  of  the  fourth  and  fifth  meta- 
carpal bones  is  more  marked  than  that  of 
the  index  and  middle  ones.  The  middle 
metacarpal  bone  is  the  least  movable.  The 
metacarpal  bone  of  the  thumb  articulates 
with  the  trapezium  by  a  saddle-shaped  joint 
which  allows  flexion,  extension,  abduction, 
adduction,  and  circumduction,  but  little  or 
no  rotation. 

Abduction,  adduction,  and  circumduc- 
tion of  the  thumb  occur  at  the  carpometa- 
carpal articulation  and  not  at  the  metacar- 
pophalangeal articulation.  This  latter  is  a 
pure  hinge-joint  and  possesses  the  move- 
ments of  flexion  and  extension  only. 

The  metacarpophalangeal  articulations 
of  the  fingers  are  practically  saddle-shaped 
joints  resembling  somewhat  the  ball-and- 
socket  joints  with  all  their  movements  ex- 
cept that  of  rotation.  They  can  be  flexed 
to  an  angle  of  90  degrees.  The  interpha- 
langeal  joints  are  hinge-joints  and  capable  only  of  flexion  and  extension.  The  second 
joint  can  be  flexed  to  an  angle  of  150  degrees  and  the  end  joint  to  about  a  right  angle. 

In  flexion  the  distal  phalanx  always  passes  under  the  proximal  bone,  thus 
causing  the  prominence  of  the  knuckle  to  be  formed  by  the  proximal  phalanx  or 
metacarpal  bone  (Fig.  366). 


Pig.  366. — Showing  how,  when  the  fingers  are 
flexed,  the  prominence  of  the  knuckles  is  formed  by 
the  projection  of  the  proximal  bone. 


MUSCLES   OF   THE    HAND. 

The  hand  contains  not  only  the  tendons  of  the  long  muscles  which  descend  into 
it  from  the  forearm,  but  also  some  short  muscles.  They  may  be  divided  into  three 
sets,  viz  :  a  middle  set,  embracing  the  interossei  and  himbricales ;  an  external  set, 
embracing  the  thumb  muscles  and  forming  the  thenar  eminence ;  and  an  internal 
set,  embracing  the  little  finger  muscles  and  forming  the  hypothenar  enihie7ice. 

The  Middle  Set. — The  interossei  muscles  arise  from  the  adjacent  sides  of  the 
metacarpal  bones;  the  lumbricales  arise  from  the  tendons  of  the  flexor  profundus  digi- 
torum.  They  all  insert  into  the  fibrous  expansion  of  the  long  extensor  tendons  at  the 
sides  of  the  proximal  phalanges  (Fig.  367).  When  they  contract  they  flex  the  proximal 
phalanx  and  extend  the  middle  and  distal  phalanges.  The  interossei  have  a  second 
insertion  into  the  sides  of  the  base  of  the  proximal  phalanx.  By  their  action  the  fingers 
may  be  separated  one  from  the  other,  or  approximated.  When  the  fingers  are  straight 
the  palmar  interossei  act  as  adductors,  while  the  dorsal  interossei  act  as  abductors. 
23 


354 


APPLIED   ANATOMY. 


The  External  Set. — The  thenar  or  thumb  eminence  has  four  muscles,  the 
abductor  poUicis,  opponens,  flexor  brevis,  and  adductor.  This  latter  is  usually  divi- 
ded into  two  parts  called  the  adductor  transversus  and  adductor  obliquus  (Fig.  368). 

The  flexor  brevis  has  two  heads,  an  outer  and  an  inner.  The  outer  head 
is  inserted  into  the  base  of  the  proximal  phalanx  on  its  outer  side  along  with  the 
abductor.  The  inner  head,  called  by  some  the  first  volar  interosseous,  is  inserted 
into  the  inner  side  along  with  the  adductor;  between  the  two  heads  runs  the  tendon 
of  the  long  flexor  of  the  thumb.  The  opponens  inserts  into  the  outer  anterior  border 
of  the  shaft  of  the  first  metacarpal  bone. 

The  Internal  Set. — The  little  finger,  like  the  thumb,  has  abductor,  oppo- 
nens, and  flexor  brevis  muscles,    but  no    adductor.     There  is,   however,  a   short 


Four  dorsal  interosseous 
muscles 

Three  palmar  inter- 
osseous muscles 


i-^_  The  two  medial 
(inner)  lumbricales 


The  two  lateral 
(outer)  lumbricales 


Fig.  367. — Showing  the  mode  of  insertion  of  the  interosseous  and  lumbrical  muscles. 

muscle,  the  palmaris  brevis,  which  is  superficial  to  the  palmar  fascia  and,  passing 
transversely  across  the  hypothenar  eminence,  inserts  into  the  skin.  It  makes  a 
dimple  on  the  ulnar  side  when  the  hand  is  hollowed.  The  abductor  and  flexor  brevis 
minimi  digiti  muscles  insert  on  the  ulnar  side  of  the  proximal  phalanx,  hence  when 
they  contract  they  tend  to  hollow  the  hand,  as  does  also  the  opponens  minimi  digiti, 
which  inserts  on  the  ulnar  side  of  the  fifth  metacarpal  bone. 


SURFACE  ANATOMY  OF  THE  HAND. 

The  hand  is  twice  as  long  as  it  is  broad.  The  length  of  the  middle  finger  from 
the  metacarpophalangeal  joint  to  its  extremity  is  equal  to  the  distance  from  the 
metacarpophalangeal  joint  to  the  radiocarpal  joint.  If  the  hand  is  turned  with  the 
palm  up,  the  thumb  diverges  from  the  median  line  at  an  angle  of  40  degrees.     The 


THE   HAND.  355 

palm  is  hollow,  with  a  muscular  mass  on  each  side.  That  on  the  thumb  side  is 
called  the  thenar  eminence  ;  it  is  formed  by  the  abductor,  opponens,  and  outer  head 
of  the  flexor  brevis  pollicis.  The  prominence  on  the  ulnar  side  of  the  hand  is  called 
the  hvpothenar  eminence  and  is  formed  by  the  abductor,  opponens,  and  flexor  brevis 
minimi  digiti.  The  palmaris  brevis  muscle  overlies  them  transversely.  The  palm  is 
marked  by  four  creases,  two  longitudinal  and  two  transverse.  One  longitudinal 
crease  begins  at  the  middle  of  the  wrist  between  the  thenar  and  hypothenar  emi- 
nences to  end  on  the  radial  side  of  the  index  finger,  opposite  the  head  of  its  meta- 
carpal bone.  It  is  caused  by  adduction  of  the  thumb.  The  other  longitudinal  crease 
runs  somewhat  parallel  to  the  first,  starting  near  the  wrist  and  ending  in   the  web 


.  Abductor  minimi  digiti 

Abductor  pollicis  •  ^^^^^^  _^^^__ 

Opponens  minimi  digiti 

^^^^^^^^^^^__^_^^   ,^^^^_^^^^^^  Flexor  brevis  minimi 

Opponens  pollicis  ^.^^^^^^^^^^^^^gaBH|^I^H^HI^^^^K         — ""^  digiti 


Flexor  brevis  pollicis"    ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ 

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^  Interossei  muscles 

Adductor  pollicis, 
oblique  portion 

Adductor  pollicis, 
transverse  portion 


\J 


\ 
\ 


Fig.  368. — Muscles  of  the  hand. 

between  the  index  and  middle  fingers.  It  is  formed  by  hollowing  the  hand.  The 
upper  transverse  crease  begins  on  the  radial  side  of  the  index  finger  where  the  first 
longitudinal  crease  ends,  and  runs  obliquely  across  the  palm  to  the  middle  of  the 
hypothenar  eminence.  It  is  formed  by  the  flexion  of  the  fingers,  especially  the 
index,  and  where  it  crosses  a  line  drawn  through  the  middle  of  the  middle  finger 
marks  the  lowest  point  of  the  superficial  palmar  arch.  The  position  of  the  lowest 
portion  of  the  superficial  palmar  arch  is  also  indicated  by  a  line  drawn  across  the  palm 
opposite  to  the  web  of  the  thumb  and  index  finger.  The  lower  transverse  crease 
begins  on  the  hypothenar  eminence  opposite  the  head  of  the  fifth  metacarpal  bone 
and  is  formed  by  the  flexion  of  the  middle,  ring,  and  especially  the  little  finger. 
When  it  reaches  the  vicinity  of  the  median  line  it  merges  with  the  second  longi- 


356  APPLIED   ANATOMY. 

tudinal  crease  which  passes  to  the  web  between  the  index  and  middle  fingers.  Mid- 
way between  the  crease  and  the  webs  of  the  fingers  he  the  joints  of  the  middle,  ring, 
and  little  finger.  More  stress  is  apt  to  be  laid  on  a  knowledge  of  these  creases  than 
they  deserve  (Fig.  369). 

The  position  of  the  metacarpophalangeal  joints  is  best  determined  by  feeling  for 
them  on  the  dorsum  of  the  hand  and  then  taking  a  corresponding  point  on  the 
palmar  surface.  They  are  sufficiently  accurately  located  by  taking  a  point  2  cm. 
(^  in.)  behind  the  web  of  the  fingers.  The  creases  for  the  middle  phalangeal  joints 
are  directly  opposite  the  articulations.  The  creases  for  the  end  phalangeal  joints  are 
to  the  proximal  side  of  the  articulations.  The  deep  palmar  arch  lies  about  1.5  cm. 
(f  in. )  closer  to  the  wrist  than  the  superficial. 

The  digital  arteries  from  the  superficial  palmar  arch  pass  downward  with  the 
digital  nerves,  superficially,  in  the  spaces  between  the  metacarpal  bones,  to  the  webs 
of  the  fingers.  About  i  cm.  (f  in.)  behind  the  web  they  sometimes  receive 
branches  from  the  deep  palmar  arch,  and  then  divide  to  go  to  each  lateral  palmar 
side  of  the  fingers.  The  palmar  fascia  divides  into  its  four  slips  just  below  the 
line  of  the  superficial  palmar  arch,  opposite  the  web  of  the  thumb. 


Fig.  369. — The  palmar  surface  of  the  hand  showing  thenar  and  hypothenar  eminences  and  creases. 

On  the  dorsum  of  the  hand  the  extensor  tendons  can  be  seen.  Accessory  slips 
usually  connect  the  tendon  of  the  ring  finger  with  that  of  the  little  finger  and  mid- 
dle finger.  A  slip  also  usually  passes  from  the  tendon  of  the  middle  to  that  of  the 
index  finger. 

The  slip  from  the  tendon  of  the  ring  to  that  of  the  little  finger  has  been  thought 
to  restrict  the  freedom  of  the  movement  of  the  ring  finger,  hence  in  musicians  it  some- 
times has  been  divided.  The  operation  is  done  by  firet  flexing  the  fingers,  which 
brings  the  slip  well  forward  near  the  knuckle,  and  then  introducing  a  thin  knife  longi- 
tudinally beneath  it  and  cutting  toward  the  skin.  The  procedure  has  not  found  favor 
among  musicians. 

The  metacarpal  bones  are  subcutaneous  and  can  readily  be  felt  their  entire 
length.  The  muscular  prominence  on  the  dorsum  of  the  hand  seen  when  the  thumb 
and  forefinger  are  approximated  is  due  to  the  abductor  indicis  muscle.  At  its  upper 
extremity  the  radial  artery  passes  between  its  two  heads  to  enter  the  palm.  When 
the  thumb  is  extended  the  snuff-box  becomes  evident  and  the  extensor  longus  poUicis 
tendon  is  distinctly  seen  leading  to  the  ulnar  side  of  the  posterior  radial  (thecal) 
tubercle  on  the  middle  of  the  dorsum  of  the  radius.  The  tendons  on  the  radial  side 
of  the  snuff-box  are  the  extensor  brevis  and  extensor  ossis  metacarpi  pollicis. 

When  the  fingers  are  flexed,  the  prominence  of  the  knuckles  is  formed  by  the  proxi- 
mal bones;  the  distal  phalanges  fold  under  the  proximal  ones  and  the  joint  line  is  about 
I  cm.  (I  in.)  below  the  dorsal  surface  of  the  metacarpal  bones  (Fig.  366,  page  353). 


THE   HAND. 


357 


THE   PALMAR   FASCIA. 

The  palmar  fascia  is  the  continuation  downward  of  the  palmaris  longus  tendon. 
It  consists  of  a  thick  triangular  middle  portion  and  two  thin  lateral  portions  which 
cover  the  thenar  and  hypothenar  eminences.  The  tria7igular  middle  portion  can  be 
divided  into  two  layers.  Its  under  layer  is  composed  of  transverse  fibres,  and  blends 
with  the  anterior  annular  ligament  ;  its  upper  layer  is  composed  of  longitudinal  fibres, 
the  continuation  of  the  palmaris  longus,  and  when  it  reaches  the  middle  of  the  palm 
it  divides  into  four  slips  which  blend  with  the  sheaths  of  the  flexor  tendons  and 


Thin  lateral  portion 
over  thenar  eminence 


Palmaris  longus  tendon 


Palmaris  brevis  muscle 


Dense  triangular  portion 
of  palmar  fascia 

Thin  lateral  portion  over 
hypothenar  eminence 


Digital  nerves 


Superficial  transveise 
ligament 


Digital  arteries 


Fig.  370. — The  palmar  fascia. 

lateral  ligaments  of  the  metacarpophalangeal  joints  to  insert  into  the  sides  of  the  base 
of  the  proximal  phalanges,  and  aid  in  flexing  them.  The  digital  arteries  and  nerves 
lie  between  these  slips  on  their  way  to  the  webs  of  the  fingers.  The  superficial  sur- 
face is  intimately  adherent  to  the  skin  above,  especially  at  the  webs  of  the  fingers, 
where  its  fibres  form  the  superficial  transverse  ligament.  The  intimate  attachment 
between  the  skin  above  and  fascia  beneath  binds  these  two  structures  so  closely  and 
firmly  together  that  pus  cannot  travel  for  any  distance  between  them.  It  either 
burrows  deeper,  or  perforates  the  skin,  or  collects  beneath  the  epiderm,  forming  a 
bleb.  A  strong  band  from  the  palmar  fascia  frequently  goes  to  the  thumb  also,  and 
when  the  palmaris  longus  contracts  it  tends  to  bring  the  thumb  forward.  The 
lateral  portions  covering  the  thenar  and  hypothenar  eminences  are  thin  and  are 
prolonged  beneath  the  long  flexor  tendons  to  become  attached  to  the  third  and  fifth 
metacarpal  bones  (Fig.  370). 


358 


APPLIED   ANATOMY. 


ARTERIES   OF   THE   HAND. 

The  hand  receives  its  blood  supply  mainly  from  the  radial  and  ulnar  arteries,  the 
amount  which  it  receives  from  the  anterior  and  posterior  interosseous  being  compar- 
atively insignificant.  The  continuation  of  the  ulnar  in  the  hand  forms  the  superficial 
palmar  arch  and  the  continuation  of  the  radial  forms  the  deep  palmar  arch  (Fig.  371). 

Ulnar  Artery  and  Superficial  Palmar  Arch.— The  ulnar  artery  at  the  wrist 
runs  along  the  edge  of  the  flexor  carpi  ulnaris   muscle  with  the  ulnar  nerve  to  its 


Ulnar  artery. 
Anterior  carpal  branch 


Deep  branch  of  ulnar 


Deep  palmar  arch 

Superficial  palmar  arc! 
Palmar  interosseous 

Palmar  digital 


Anterior  (volar)  interosseous 


Radial  artery- 


Anterior  carpal  branch 


Superficial  volar 


Princeps  pollicis 


Radialis  indicis 


Fig.  371. — The  arteries  of  the  hand. 

inner  or  ulnar  side.  As  it  enters  the  hand  it  lies  just  to  the  radial  side  of  the  pisiform 
bone  with  the  nerve  intervening.  Both  the  artery  and  nerve  lie  on  the  anterior 
annular  ligament.  As  soon  as  they  pass  the  pisiform  bone  they  go  under  the  small 
palmaris  brevis  muscle  and  the  palmar  fascia,  and  lie  on  the  flexor  tendons. 

The  artery  then  describes  a  curve  across  the  palm  of  the  hand  toward  the  web 
of  the  thumb.  It  crosses  the  middle  of  the  third  metacarpal  bone  at  or  a  little  above 
the  level  of  the  web  of  the  thumb  and  continues  on  to  the  radial  side  of  the 
metacarpal  bone  of  the  index  finger.  Here  it  receives  the  superficial  volar  artery 
from  the  radial  as  well  as  a  communicating  branch  from  the  princeps  pollicis  and 


THE  HAND. 


359 


radialis  indicis.  When  one  of  these  branches  is  large  the  other  two  are  smaller  or 
lacking  altogether.  Not  infrequently  the  communication  with  the  radial  at  this  point 
is  in  the  form  of  a  large  branch  which  passes  superficially  across  the  web  of  the  thumb 
and  index  finger,  and  its  pulsations  can  be  both  seen  and  felt  (Fig.  372). 

Branches. — As  soon  as  the  ulnar  artery  passes  the  pisiform  bone  it  gives  oH  its 
deep  branch  which  passes  down  between  the  abductor  and  flexor  brevis  minimi  digiti  to 
join  the  termination  of  the  radial  and  form  the  deep  palmar  arch.  From  the  convexity 
of  the  superficial  arch  four  palmar  digital  arteries  are  given  off.  One  goes  to  the  ulnar 
side  of  the  little  finger  while  the  other  three  go  down  between  the  metacarpal  bones 


Ulnar  artery 

Deep  branch  of  ulnar  artery 
Deep  branch  of  ulnar  nerve 


Superficial  palmar  arch 


Palmar  digital 
arteries 


Radial  artery 


Superficial  volar  artery 


Fig.  372. — Superficial  palmar  arch. 

to  the  webs  of  the  fingers.  Here  they  may  receive  a  small  communicating  branch 
derived  from  the  deep  palmar  arch,  and  about  i  cm.  (fin.)  back  from  the  web 
divide  into  collateral  digital  branches  which  run  along  the  palmar  sides  of  the  fingers. 
The  digital  nerves  as  they  accompany  the  digital  arteries  are  superficial  to  them. 

The  Radial  Artery  and  Deep  Palmar  Arch. — The  radial  artery  reaches 
the  wrist  between  the  brachioradialis  and  flexor  carpi  radialis  tendons.  It  then  turns 
sharply  toward  the  dorsum  around  the  extremity  of  the  styloid  process  of  the  radius. 
It  crosses  the  external  lateral  ligaments  and  the  scaphoid  and  trapezium  bones  to 
enter  the  palm  between  the  bases  of  the  metacarpal  bones  of  the  thumb  and  index 
finger.      It  then  passes  across  the  palm  to  the  fifth  metacarpal  bone,  where  it  receives 


36o  APPLIED    ANATOMY. 

the  deep  branch  of  the  ulnar,  which  completes  the  formation  of  the  deep  arch.  It 
lies  beneath  the  flexor  tendons  and  on  the  interossei  muscles  and  bases  of  the  meta- 
carpal bones  (Fig.  373J. 

Branches. — The  radial  artery  at  the  wrist  gives  oH  a  posterior  carpal  branch 
which  anastomoses  with  the  posterior  carpal  branch  of  the  ulnar  to  form  a  posterior 
carpal  arch.  From  this  arch  descend  three  posterior  interosseous  arteries.  The 
dorsal  interosseous  artery  lying  to  the  radial  side  of  the  index  finger  is  called  the 
dorsalis  indicts.  It  comes  off  separately  from  the  radial,  and  may  be  a  branch  from 
the  radialis  indicis. 

As  the  radial  artery  enters  the  palm  it  gives  off  a  large  branch  to  the 
thumb  called  the  princeps  pollicis,  and  one  to  the  palmar  side  of  the  index  called 
the  radialis  indicis.  Farther  on,  three  palmar  interosseous  branches  are  given  of? 
which  communicate  at  the  webs  of  the  fingers  with  the  palmar  digital  arteries  from 
the  superficial  arch.  The  deep  palmar  arch  also  sends  a  few  recurrent  branches  up 
on  the  anterior  surface  of  the  carpus  and  three  perforating  branches  between  the 
metacarpal  bones  to  the  back  of  the  hand. 

NERVES    OF   THE    HAND. 

The  hand  is  supplied  by  the  median,  uhiar,  and  radial  (musculospiral)  nerves. 
They  are  of  clinical  importance  on  account  of  the  paralysis  of  the  muscles  or  disturb- 
ance of  sensation  which  accompany  their  injury  (Fig.  374). 

Muscular  Branches. 

r  Abductor  pollicis. 
Opponens  pollicis. 
Median  Nerve \   Outer  head  of  flexor  brevis. 

[  First  and  second  lumbricales. 

Ulnar  Nerve To  all  the  rest  of  the  hand  muscles. 

Superficial  Branch Palmaris  brevis. 


I 


r 


Abductor  minimi  digiti. 

Flexor  brevis  minimi  digiti. 
I   Opponens  minimi  digiti. 
Ueep  Brancli j   Adductor  transversus  and  obliquus  pollicis. 

Inner  head  of  flexor  brevis  pollicis. 
1  Two  inner  lumbricales. 
I  All  the  interossei. 

Cutaneous  Branches. 
Palmar  Surface. 

(  Entire  radial  side  of  the  palm  over  to  the 

Median  Nerve '        middle  of  the  ring  finger  and  the  groove 

I       at  the   wrist  between   the  thenar  and 
^      hypothenar  eminences. 
Ulnar  side  of  the  little  finger,  and  adjacent 
sides     of    little   and   ring   fingers    and 

Ulnar  Nerve J       hypothenar   eminence.     The    adjacent 

I       branches    of    the    ulnar    and    median 
I       nerves  anastomose. 

Dorsal  Surface. 


Ulnar  side  of  thumb  and  matrix  of  nail 
Median  Nerve \ 


f 

!       Distal  half  of  the  index  and  middle  fin- 


gers and  distal  half  of  the  radial  side  of 
^      the  ring  finger. 

(  Both  sides  of  the  little  finger  and  ulnar 
Ulnar  Nerve \       side  of  ring  finger. 

f  Both  sides  of  thumb  as  far  as  the  nail, 
anastomosing  with  the  median  on  the 
ulnar  side.  Proximal  half  of  the  index 
and,  with  the  ulnar,  the  proximal  half 
of  the  middle  and  radial  side  of  the  ring 


Radial  Nerve 

j 

I 


I      finger. 


THE   HAND. 


361 


Radial  artery 
Superficial  volar  artery 


Princeps  pollicis 
Radialis  indicia 


Deep  palmar  arch 


Palmar  interosseous  arteries 


Fig.  373. — The  deep  palmar  arch 


Fig.  374. — Showing  the  distribution  of  the  nerves  of  the  back  of  the  hand. 


362 


APPLIED   ANATOMY. 


DISLOCATIONS   OF   THE   HAND. 

The  carpal  bones  are  so  firmly  held  in  place  by  their  ligaments  that  they  are 
rarely  luxated.  Dislocations  of  the  scaphoid  and  semilunar  however  are  sometimes 
encountered. 

Dislocations  of  the  Bases  of  the  Metacarpal  Bones. — Dislocations 
sometimes  occur  toward  the  dorsal  surface.  The  bases  of  the  second  and  third  met- 
acarpal bones  in  the  uninjured  hand  form  a  bony  prominence  on  the  dorsum  of  the 


Fig.  375. — Dislocation  of  proximal  phalanx  of  little  finger.   (From  author's  sketch.) 

hand  which  may  be  mistaken  for  a  luxation.  This  prominence  lies  in  a  direct 
line  with  the  posterior  radial  (or  thecal)  tubercle  and  about  4  cm.  (1}^  in.)  below  it. 

The  bases  of  the  metacarpal  bones  and  carpometacarpal  joints  are  best  recog- 
nized by  following  up  the  interosseous  spaces  by  making  firm  pressure  with  the 
fingers  between  the  bones  ;  when  the  upper  limit  of  the  space  is  reached  the  joints 
can  be  located  1.25  cm.  (}4  in.)  above. 

Dislocations  of  the  Phalanges  on  the  Metacarpal  Bones. — These  dislo- 
cations occur  with  moderate  frequency.  Dislocation  of  the  thumb  occurs  most 
frequently  and  is  well  known.     The  little  finger  is  next  in  frequency,  while  the  other 


Fig.  376. — Dorsal  luxation  of  the  proximal  phalanx  of  the  thumb,  showing  the  position  of  the  bones. 

three  are  rarely  luxated.  When  luxation  of  the  proximal  phalanx  of  the  little  finger 
occurs  it  acts  precisely  as  does  that  of  the  thumb  (as  I  have  seen  in  one  case,  Fig. 
375).  As  the  thumb  dislocation  is  the  most  troublesome  it  alone  will  be  described. 
Dislocation  of  the  Proximal  Phalanx  of  the  Thumb. — This  displacement  occurs 
when  the  thumb  is  hyperextended  on  its  metacarpal  bone  (Figs.  376  and  377),  and  it 
is  often  impossible  to  reduce  it  without  division  of  the  resisting  structures.  The 
head  of  the  metacarpal  bone  is  much  larger  than  the  shaft  immediately  behind  it  and 
projects  especially  on  its  palmar  surface  toward  each  side,  forming  two  tubercles. 


THE   HAND. 


363 


The  joint  has  two  lateral  ligaments  and  an  anterior  or  glenoid  ligament.  These 
are  more  firmly  attached  to  the  phalanx  than  to  the  metacarpal  bone,  so  that  in 
dislocation  they  are  torn  from  the  latter. 

Inserting  into  the  outer  side  of  the  base  of  the  proximal  phalanx  are  the  tendons 
of  the  abductor  and  outer  head  of  the  fiexor  brevis  poUicis.  They  blend  with  the 
lateral  ligament  and  have  developed  in  them  a  sesamoid  bone  which  rides  on  the 
tubercle. 

Inserting  into  the  inner  side  of  the  base  of  the  proximal  phalanx  are  the  inner 
head  of  the  flexor  brevis  and  the  adductor  obliquus  and  transversus  poUicis  muscles. 
They  blend  with  the  lateral  ligament  and  contain  a  sesamoid  bone  which  rides  on  the 


Abductor  pollicis 
Flexor  brevis  pollicis 

Flexor  longus  pollicis 


Fir,.  377. — Dorsal  luxation  of  the  proximal  phalanx  of  the  thumb:  Division  of  the  tendons  of  the  abductor  and 

flexor  brevis  pollicis  muscles. 


inner  tubercle.      The  flexor  longus  pollicis  tendon  passes  between  the  two  tubercles 
and  sesamoid  bones. 

When  the  thumb  is  hyperextended  the  glenoid  and  lateral  ligaments  are  torn 
loose  from  the  metacarpal  bone  and  carry  with  them  the  tendons  and  sesamoid  bones 
already  described.  The  head  of  the  metacarpal  bone  projects  forward  in  the  palm 
and  can  be  felt  beneath  the  skin  ;  the  flexor  longus  pollicis  tendon  slips  to  the  inner 
side  of  the  bone.  As  the  head  pierces  the  capsule  the  latter,  strengthened  by  the 
tendons  of  the  short  muscles  of  ""he  thumb, 
contracts  behind  it  like  a  collar  and  pre- 
vents reduction. 

Reduction  is  to  be  attempted  by  ex- 
tending the  phalanx  until  it  is  at  right 
angles  with  the  metacarpal  bone  and  drag- 
ging its  base  forward  over  the  head  of  the 
metacarpal  bone  and  then  flexing. 

If  this  is  not  successful,  then  by  means 
of  a  narrow  knife,  either  through  an  open 
wound  or  subcutaneously,  the  lateral  ligament  and  tendons  on  one  side  (the  radial) 
are  loosened  from  the  base  of  the  phalanx,  which  can  then  be  brought  forward. 
This,  of  course,  divides  the  tendinous  collar  which  prevents  reposition  (Fig.  377). 

Dislocations  of  the  Middle  and  Distal  Phalanges. — These  frequently 
occur  in  playing  ball  games.  In  attempting  to  catch  the  ball  the  tip  of  the  finger 
may  be  struck  and  the  phalanx  hyperextended  and  thereby  luxated  (Fig.  378). 

These  luxations  are  usually  readily  reduced  by  simple  traction  and  flexion. 
Sometimes,  however,  reduction  is  not  complete,  or  there  is  a  concomitant  fracture, 
hence  the  crippled  and  deformed  fingers  so  often  seen  in  the  case  of  base-ball  players. 

A  tearing  loose  of  the  attachment  of  the  extensor  tendon  allows  the  distal 
phalanx  to  fall,  producing  what  Stern  has  called  drop  phalangette. 


Fig.  378. — Dislocation  of  the  terminal  phalanx,  show- 
ing the  position  of  the  bones.  (From  author's  slcetch.) 


364  ^^V  APPLIED   ANATOMY. 

FRACTURES  OF  THE  HAND. 

Fractures  of  the  carpal  bones  are  often  only  suspected  or  detected  by 
means  of  a  skiagraph.  They  are  quite  rare  and  are  almost  impossible  to  distinguish 
clinically  from  ordinary  sprains. 

Fractures  of  the  metacarpal  bones  are  more  common.  The  bones  are 
subcutaneous  on  the  dorsum  of  the  hand  and  can  be  readily  felt  throughout  their 
entire  length.  They  are  not  infrequently  broken  by  a  blow  on  the  end  of  the  bone 
in  fighting.  Hamilton  states  that  in  every  case  in  which  the  fracture  has  been  pro- 
duced by  a  blow  on  the  knuckles  the  distal  end  of  the  distal  fragment  has  been 
drawn  toward  the  palm  and  its  proximal  end  projected  toward  the  dorsum.  This  is 
accounted  for  by  the  greater  strength  of  the  flexor  muscles. 

The  first,  third,  and  fourth  metacarpophalangeal  joints  have  one  extensor  tendon, 
the  extensor  communis  digitorum.  The  second  and  fifth  have  in  addition  the  extensor 
indicis  and  the  extensor  minimi  digiti.  There  are  two  powerful  flexors,  the  sublimis 
and  profundus,  and  these  are  aided  by  the  palmaris  longus,  interossei,  and  lumbri- 
cales  muscles.  In  one  case  Hamilton  saw  a  dorsal  projection  of  the  proximal  frag- 
ment which  he  believed  to  be  due  to  the  action  of  the  extensor  carpi  radialis  muscle 
because  the  deformity  became  less  marked  when  the  hand  was  bent  backward  and 
the  tendon  relaxed. 

On  anatomical  grounds  one  would  expect  this  dorsal  displacement  to  occur 
in  fractures  of  the  third  metacarpal  bone.  It  has  only  one  carpal  tendon  inserting 
into  it,  the  extensor  carpi  radialis  brevior.  The  second  has  the  flexor  carpi  radialis 
inserting  on  its  palmar  surface  and  the  extensor  carpi  radialis  longior  on  its  dorsal 
surface. 

The  fifth  metacarpal  bone  has  the  flexor  carpi  ulnaris  on  its  palmar  surface  and 
the  extensor  carpi  ulnaris  on  its  dorsal  surface.  Hence  it  would  be  expected  that 
the  flexor  and  extensor  muscles  would  neutralize  each  other. 

In  order  to  relax  the  parts  as  well  as  to  allow  for  the  concavity  of  the  palmar 
surface  of  the  metacarpal  bones  a  rounded  pad  is  to  be  placed  in  the  palm  and  the 
hand  placed  on  a  splint ;  sometimes  an  additional  flat  pad  and  small  dorsal  splint  is 
of  service.  Care  should  be  taken  not  to  displace  the  fragments  laterally  by  con- 
stricting the  hand  with  the  bandage. 

Fractures  of  the  Phalanges. — These  are  frequently  compound,  necessitating 
amputation.  Fracture  of  the  proximal  phalanx  necessitates  a  splint  extending  into 
the  hand,  but  for  the  middle  and  distal  phalanges  a  short  splint  is  sufficient.  The 
action  of  the  interossei  and  lumbricales  through  their  insertion  into  the  extensor 
tendon  is  liable  to  draw  the  distal  fragment  toward  the  dorsum  if  the  fracture  is 
left  untreated. 

A  knowledge  of  the  exact  position  of  the  joints  is  essential  to  avoid  mistaking 
fractures  and  dislocations  for  one  another. 

WOUNDS   OF   THE  HAND. 

Wounds  of  the  hand,  owing  to  the  free  blood  supply,  heal  rapidly.  An  excep- 
tion, however,  is  to  be  made  in  the  case  of  the  tendons.  These  frequently  slough. 
If  the  tendons  are  divided  they  are  to  be  immediately  united  with  sutures,  otherwise 
they  retract  into  their  sheaths. 

If  nerves  are  divided  where  they  are  large,  as  near  the  wrist,  they  should  be 
sutured,  because  they  are  partly  motor  and  supply  the  short  muscles  of  the  hand  ; 
but  if  the  digital  nerves  are  divided  they  need  not  be  sutured  as  they  are  only  sen- 
sory. The  median  nerve  enters  the  palm  to  the  radial  side  of  the  median  line,  and 
its  position  can  be  determined  by  following  down  the  interval  between  the  tendons  of 
the  palmaris  longus  and  flexor  carpi  radialis  muscles. 

The  ulnar  nerve  lies  immediately  to  the  radial  side  of  the  pisiform  bone. 

Bleeding  from  wounds  of  the  hand  is  not  infrequently  troublesome.  The  deep 
arch  may  be  injured  in  a  wound  about  2.5  cm.  (i  in.)  below  the  lower  crease  on  the 
anterior  surface  of  the  wrist.      Its  position  can  also  be  approximately  determined  by 


THE   HAND.  365 

feeling  for  the  upper  end  of  the  first  interosseous  space  on  the  dorsum  of  the  hand 
and  selecting  a  spot  at  a  corresponding  level  on  the  palmar  surface.  It  lies  deep 
beneath  the  palmar  fascia  and  flexor  tendons  and  nerxes,  and  necessitates  too  great  a 
disturbance  of  the  parts  to  expose  it  for  ligation  ;  hence,  when  wounded,  bleeding 
from  it  is  checked  by  packing  the  wound  with  antiseptic  gauze.  A  curved  line, 
convex  downward,  from  the  radial  side  of  the  pisiform  bone  to  the  web  of  the  thumb, 
describes  approximately  the  course  of  the  superficial  palmar  arch.  It  lies  immedi- 
ately beneath  the  palmar  fascia,  and  if  it  bleeds  freely  can  be  exposed  by  an  incision 
and  tied.  The  incision  should  preferably  be  a  longitudinal  one  to  avoid  wounding 
the  digital  arteries  and  nerves.  The  superficial  palmar  arch  lies  superficial  to  the 
tendons  and  they  should  not  be  disturbed.  The  digital  ner\es  come  down  beneath 
the  palmar  arch,  so  that  they  need  not  be  wounded  in  ligating  it.  As  they  reach  the 
webs  of  the  fingers  the  nerv^es  become  superficial  to  the  arteries,  and  in  the  fingers 
they  lie  anterior  and  nearer  the  median  line.  The  fingers  are  usually  supplied  with 
blood  from  the  superficial  palmar  arch,  and  the  digital  arteries  between  the  palmar 
arch  and  webs  of  the  fingers  may  be  quite  large.  Sometimes  the  fingers  are  supplied 
by  large  digital  branches  from  the  deep  palmar  arch,  then  those  from  the  superficial 
will  be  correspondingly  small. 

In  uniting  the  several  ends  of  tendons  the  two  ends  of  the  same  tendon  should 
be  joined  and  not  the  flexor  sublimis  joined  to  the  profundus  and  vice  versa. 

ABSCESSES  OF  THE  HAND  AND  FINGERS. 

Purulent  collections  in  the  palm  of  the  hand  are  located  either  beneath  the 
palmar  fascia  or  are  connected  with  the  sheaths  of  the  flexor  tendons.  When  the 
fingers  are  affected  the  pus  may  be  either  in  the  sheaths  of  the  tendons  or  in  the  cell- 
ular tissue  beneath  the  skin. 

Abscess  Beneath  the  Palmar  Fascia. — As  a  result  of  infected  wounds  pus 
may  accumulate  beneath  the  palmar  fascia.  The  construction  of  this  fascia  (see 
page  357)  limits  the  spread  of  the  pus  in  some  directions  and  favors  it  in  others. 
Pus  originating  beneath  the  thick  middle  triangular  portion  will  tend  to  point  to 
either  side,  and  it  may  show  on  the  inner  side  at  the  hypothenar  eminence,  or  work 
toward  the  outer  side  and  point  in  the  web  of  the  thumb  (Fig.  379). 

It  may  take  an  upward  course  and  pass  under  the  annular  ligament  to  point  on 
the  anterior  surface  of  the  forearm  above  the  wrist. 

If  it  tends  downward  it  escapes  through  the  openings  for  the  exit  of  the  digital 
arteries  and  nerves,  and  shows  in  the  webs  of  the  fingers. 

If  it  extends  still  farther  it  burrows  between  the  distal  extremities  of  the  meta- 
carpal bones  and  shows  on  the  back  of  the  hand. 

Sometimes  the  pus  works  directly  toward  the  surface  through  small  gaps  in  the 
fascia.  In  such  cases  a  small  amount  of  pus  may  accumulate  above  the  palmar  fascia 
and  between  it  and  the  skin  ;  so  that  there  is  a  collection  of  pus  both  above  and 
below  the  fascia,  communicating  through  a  hole  in  the  fascia.  This  is  called  an 
hour  glass  abscess,  or  the  abces  en  bissac  of  the  French. 

In  opening  such  abscesses,  if  their  character  is  not  recognized  the  surgeon  may 
only  incise  the  superficial  of  the  two  collections  and  fail  to  evacuate  the  deeper  and 
more  serious  one. 

In  incising  palmar  abscesses  the  only  safe  way  is  to  limit  the  incision  to  the  skin 
and  open  the  deep  parts  by  inserting  a  closed  pair  of  forceps  and  then  separating 
its  blades.  Incisions  should  not  be  made  nearer  to  the  wrist  than  on  a  level  with 
the  web  of  the  thumb,  or  the  superficial  palmar  arch  may  be  cut.  The  spaces 
between  the  metacarpal  bones  are, occupied  by  the  digital  arteries  and  nerves  ;  hence 
any  longitudinal  incisions  should  be  made  over  the  tendinous  sheaths  and  metacarpal 
bones.  Usually  it  is  not  necessary  to  carry  the  incision  so  deep  as  to  open  the 
sheaths.  Incisions  over  the  second,  third,  and  fourth  metacarpal  bones  are  tolerably 
certain  to  avoid  the  digital  arteries,  but  an  incision  over  the  fifth  is  liable  to  wound  the 
artery  going  to  the  ulnar  side  of  the  little  finger  as  it  crosses  oxer  from  the  superficial 
palmar  arch.  These  arteries  of  the  palm  are  also  liable  to  be  more  or  less  irregular 
in  their  location,  hence  it  is  better  to  avoid  using  the  knife  in  the  deeper  structures. 


366 


APPLIED   ANATOMY. 


Suppuration  in  the  Sheaths  of  the  Tendons.  —  If  the  sheath  of  the 
tendons  of  the  hand  or  fingers  become  infected,  either  by  being  penetrated  by  a 
foreign  body  or  by  extension  from  the  surrounding  tissues,  the  pus  traxels  along 
the  tendon  as  far  as  the  sheath  extends. 

The  sheaths  of  the  tendons  vary  in  their  extent.  The  flexor  profundus  and 
subUmis  tendons  he  together  in  single  sheaths,  which  commence  at  the  base  of  the 
distal  phalanx.  That  of  the  thumb  follows  the  long  flexor  tendon  up  the  thumb,  be- 
neath the  annular  ligament,  to  3  or  4  cm.  (i}4  in.)  above  the  wrist;  that  of  the  little 
finger  passes  up  to  almost  opposite  the  level  of  the  web  of  the  thumb  and  then 
spreads  over  toward  the  radial  side  and  envelops  the  remaining  tendons  of  the  other 
three  fingers,  forming  the  great  carpal  bursa  which  extends  up  under  the  annular 
ligament  to  3  or  4  cm.  above  the  wrist  (Fig.  380). 

The  sheaths  of  the  remaining  three  fingers  extend  only  to  the  heads  of  the  met- 
acarpal bones,  about  2  cm.  (  ^  in. )  above  the  webs  of  the  fingers.     This  would  leave 


Pointing  above  the  anterioi 

annular  ligament 


Pointing  on  each  side  of  the 
triangular  portion  of  the 
palmar  fascia 


Pointing  between  the  fibres 
of  the  palmar  fascia 


Pointing  in  the  webs  of  the  fingers 


Fig.  379. — Cadaveric  preparation  with  wax  injected  beneath  the  palmar  fascia  to  illustrate  where  palmar  abscesses 

tend  to  find  an  exit. 


a  space  of  about  2  cm.  (  ^  in. )  intervening  between  the  proximal  ending  of  the  tendon 
sheaths  of  the  middle  three  fingers  and  the  great  carpal  bursa.  This  is  the  usual 
arrangement,  but  not  infrequently  the  sheath  for  the  little  finger  ends,  as  do  the 
other  three,  opposite  the  head  of  the  metacarpal  bone,  or  it  may  go  up  the  entire 
way  to  the  wrist  as  a  separate  sheath,  in  which  case  the  great  carpal  bursa  en\'elops 
only  the  tendons  of  the  index,  middle,  and  ring  fingers. 

When  suppuration  occurs  in  the  sheath  of  the  thumb  or  little  finger  it  is  much 
more  serious  than  in  the  other  three,  because  the  pus  tends  to  travel  directly  upward 
and  involve  the  palm,  and  go  even  above  the  wrist.  When  suppuration  involves  the 
index,  middle,  or  ring  fingers  it  stops  when  it  reaches  the  vicinity  of  the  metacarpo- 
phalangeal joints  and  involves  the  palm  and  carpal  bursa  only  by  breaking  through 
its  own  sheath  and  breaking  into  the  carpal  sheath.  This  it  is  not  likely  to  do 
unless  the  infection  is  virulent  and  the  suppuration  abundant. 

Suppuration  Involving  the  Fingers. — When  suppuration  occurs  in  the 
middle  or  proximal  phalanx  the  pus  may  occupy  the  tissue  between  the  skin  and 
tendon  and  not  involve  its  sheath,  hence  is  not  liable  to  extend  rapidly.     When  the 


THE   HAND. 


367 


end  phalanx  is  affected  the  affection  is  known  as  panaris,  whitlow,  felon,  etc.  The 
pulp  of  the  finger  resembles  that  of  the  heel,  the  scalp,  the  palm  of  the  hand,  etc., 
in  the  fact  that  the  under  surface  of  the  skin  sends  oft'  firm  fibrous  bands  or  fibrils 
which  are  attached  to  the  parts  beneath.      The  spaces  between  these  fibrils  are  filled 


Sheath  of  flexor 
longus  pollicis 


Palmar  bursa 


Shealiisui  hexor 
tendons  of  the  index, 
middle  and  ring  finger 


Sheath  of  flexor 
endons  of  little  finger 


Fig.  380. — Palmar  bursa  and  sheaths  of  the  flexor  tendons  distended  with  wax. 

in  with  fatty  tissue  and  vessels,  nerves  and  lymphatics  (Fig.  381).  Infection  begins 
in  the  skin  through  some  small  wound,  as  the  tearing  of  the  nail,  pin-punctures,  etc., 
and  involves  the  fatty  tissue  beneath.     If  exit  is  not  given  to  the  pus  it  is  often  unable 

Extensor  communis  digitorum  — 


Flexor  profundus  digitorurr. 
Flexor  sublimis  digitorurr 


Fig.  381. 


-Longitudinal  section  of  the  end  of  a  finger,  showing  the  pulp  and  mode  of  termination  of  the  tendons  in 

the  distal  phalanx. 


to  break  through  the  hard  skin  on  the  surface.  Since  the  fibrous  bands  prevent 
swelling  to  any  extent,  it  burrows  deeper  and  involves  the  periosteum  along  which 
it  proceeds  to  the  region  of  the  joint,  here  it  may  enter  the  sheath  of  the  tendon 
when  it  rapidly  proceeds  upward  as  far  as  the  sheath  extends. 


368 


APPLIED    ANATOMY. 


Bone  felons  are  not  as  a  rule  primary  in  their  origin,  unless  syphilitic  in  charac- 
ter, but  arise  secondarily  by  extension  from  the  skin  above. 

LYMPHATICS   OF   THE    HAND. 

The  hand  and  fingers  are  abundantly  supplied  with  lymphatics  which  begin  in 
a  plexus  around  the  matrix  of  the  nail  and  the  pulp  of  the  fingers  and  unite  to  form 
lymphatic  trunks  which  proceed  up  the  wrist  and  forearm.  There  are  both  superficial 
and  deep  sets,  which  communicate  at  the  wrist. 

The  deep  set  follows  the  arteries  of  the  forearm  and  arm  to  the  axilla.  This  set 
sometimes  possesses  a  few  nodes  in  the  forearm  and  one  at  the  flexure  of  the  elbow. 

The  superficial  set,  both  anteriorly  and  posteriorly,  concentrates  in  the  supra- 
trochlear nodes  and  thence  proceeds  to  the  axilla.  Some  of  the  lymphatic  vessels 
pass  by  the  supratrochlear  nodes  and  empty  direct  into  the  axillary  nodes  (Fig.  382). 

In  infections  of  the  fingers  or  hand  the  infection  follows  the  lymphatic  trunks, 
which  can  be  seen  as  red  lines  running  up  the  forearm.  Suppuration  may  involve 
the  supratrochlear  and,  later,  the  axillary  nodes.      As  some  of  the  lymphatic  trunks 


I 


Fig.  382. — Superficial  lymphatic  vessels  of  upper  limb;  semidiagrammatic.     {.Based  on  figures  of  .Sappey.; 

pass  by  the  supratrochlear  nodes  to  empty  direct  into  the  axillary  nodes  there  may 
be  infection  of  the  latter  without  any  implication  of  the  former.  Enlargement 
and  inflammation  of  the  occasionally  present  deep  lymphatic  nodes  of  the  forearm  is 
clinically  unknown,  so  it  may  be  said  that  practically  there  are  no  lymphatic  nodes 
below  the  supratrochlear  ones. 

AMPUTATIONS   OF   THE  THUMB   AND   FINGERS. 

In  these  amputations  it  is  particularly  necessary  to  be  able  to  accurately  locate 
the  joints.  The  distal  phalanx  when  flexed  always  passes  under  the  proximal  one. 
When  the  flexor  and  extensor  tendons  are  cut  they  should  be  sewed  either  to  their 
sheaths  or  united  to  one  another  over  the  ends  of  the  bone. 


AMPUTATIONS  OF  THE  THUMB. 


Distal  Phalanx.  —  In  removing  the  distal  phalanx  the  joint  is  opened  by  an 
incision  across  the  dorsum  in  a  line  with  the  middle  of  the  side  of  the  proximal  pha- 
lanx. A  long  flap  is  to  be  cut  from  the  palmar  surface.  As  the  flexor  and  extensor 
tendons  are  inserted  into  the  base  of  the  distal  phalanx,  it  will  be  an  advantage  to 
retain  it  if  possible.     The  digital  arteries  may  even  here  require  ligation. 


THE   HAND. 


369 


Metacarpophalangeal  Amputation. — Lateral  flaps  are  usually  used.  They 
are  often  made  too  short  because  the  joint  is  thought  to  be  higher  than  it  really  is. 
By  flexing  the  thumb  to  a  right  angle  the  joint  can  be  felt  on  the  dorsum  about 
8  mm.  (yi  in.  )  below  the  top  of  the  knuckle.  The  flaps  must  be  cut  as  far  forward  as 
the  middle  of  the  phalanx.  The  two  digital  arteries  on  the  palmar  surface  will 
require  torsion  or  ligation.  If  the  base  of  the  phalanx  can  be  retained  the  attach- 
ments of  the  short  muscles  of  the  thumb  are  preserv^ed  and  additional  control  is  given 
to  the  stump. 

Carpometacarpal  Amputation. — The  upper  limit  of  the  metacarpal  bone 
may  often  be  difticult  to  recognize.      The  best  way  to  locate  it  is  to  feel  for  the  snuff- 
box and  then   feel   for  the  joint  a  centi- 
metre (say  a  half  inch)   in  front  of  it.      The  ^Extensor  communis  digitorum 

dorsalis  poUicis  artery  running  on  the  dor- 
sum of  the  bone  and  the  princeps  poUicis  ,^_^^.^^^ 

on  its  palmar  aspect  may  require  ligation.         /ftlKS9]^fk'  '^'^''"'^  s^biimis  digitorum 
In  disarticulating,  it  should  be  remembered        f^^^^^f^af- Digital  artery 
that  the  joint  is  curved  with  its  convexity 
toward  the  wrist. 


Digital  nerve 


AMPUTATIONS   OF  THE   FINGERS. 


Flexor  profundus  digitorum 


Fig.   383.- 


A    transverse   section  of  the   proximal 
phalanx. 


In  amputating  the  fingers,  although  it 
is  easier  to  amputate  through  the  joints, 
it  is  better  to  cut  through  the  bone  and  save  part  of  the  phalanx,  because  much 
better  control  over  the  movements  is  obtained  on  account  of  the  insertion  of  the 
tendons  into  the  base  and  sides  of  the  phalanges.  Into  the  base  of  the  distal 
phalanx  is  inserted  the  common  extensor  and  flexor  profundus  digitorum.  Into  the 
base  of  the  middle  phalan.x  on  its  dorsal  surface  is  inserted  the  extensor  communis 
digitorum,  which  is  reinforced  by  the  lumbricales  and  interossei ;  on  its  palmar 
surface  is  inserted  the  flexor  sublimis  digitorum.      Into  the  bases  of  the  proximal 


Fio.  384.— Lines  of  incision  for  amputations  at  the  carpometacarpal  joint  of  the  thumb,  the  metacarpophalangeal 
joint  of  the  index  finger  and  between  the  pro.ximal  and  middle  phalanges  of  the  middle  finger. 


phalanges  are  inserted  the  interossei  muscles.  The  lines  of  the  joints  are  to  be  recog- 
nized by  remembering  that  the  distal  phalanx  always  flexes  beneath  the  pro.ximal 
one,  therefore  the  prominence  is  always  formed  by  the  head  of  the  proximal  bone. 

The  joint  is  to  be  opened  by  an  incision  across  its  anterior  surface  when  flexed, 
and  not  on  its  dorsal  surface.  Anterior  or  palmar  flaps  are  always  used,  except 
at  the  metacarpal  joints.  The  digital  arteries  lie  on  the  lateral  palmar  surface  on 
each  side  of  the  flexor  tendons  and  may  require  torsion  or  ligation.  The  finger- 
joints  have  lateral  ligaments  and  a  palmar  or  glenoid  ligament.  On  the  dorsal 
surface  there  is  no  ligament,  its  place  being  filled  by  the  extensor  tendon  (Fig.  383). 

Metacarpophalangeal  Amputations.^Lateral  flaps  are  used  in  disarticu- 
lating at  the  metacarpal  joints.  In  a  well-developed  hand  the  line  of  the  joint  will 
be  1.25  cm.  (}4  in.)  below  the  dorsal  surface  of  the  metacarpal  bone  (Fig.  384). 

In  consequence  of  not  first  recognizing  the  position  of  the  joint  the  flaps  are 
often  cut  too  short.  The  incision  must  not  involve  the  webs  of  the  fingers  but 
should  reach  as  far  forward  as  the  middle  of  the  phalanx.      If  this  is  not  done  it  will 

24 


370  W^^^       APPLIED    ANATOMY.  ^^Hi^Him 

necessitate  resection  of  the  head  of  the  metacarpal  bone,  which  will  materially  weaken 
the  hand.  The  two  palmar  digital  arteries  will  require  ligation,  and  the  tendons 
should  be  sutured  over  the  face  of  the  bone  or  to  their  sheaths,  closing  them. 

THE  ABDOMEN. 

The  abdomen  comprises  that  part  of  the  body  anterior  to  the  spine  and  erector 
spince  and  quadratus  lumborum  muscles,  and  from  the  diaphragm  above  to  the  rim 
of  the  pelvis  below.  The  true  pelvis  is  not  included.  The  peritoneal  cavity  em- 
braces the  cavity  of  the  abdomen  and  also  that  of  the  pelvis.  An  accurate  knowledge 
of  the  topographical  anatomy  of  the  abdomen  with  its  various  contained  organs  is 
absolutely  essential  to  both  the  physician  and  the  surgeon  for  diagnostic  purposes, 
and  especially  to  the  latter  in  carrying  out  his  operative  procedures.  The  surface  of 
the  abdomen  should  be  studied  with  reference  to  physical  diagnosis ;  its  walls, 
because  herniae  frequently  protrude  through  them,  and  because  they  must  be  tra- 
versed in  obtaining  access  to  the  structures  within;  its  contents,  in  order  to  properly 
carry  out  necessary  operative  measures. 

SURFACE  ANATOMY  OF  THE  ABDOMEN. 

The  rounded  form  of  the  abdomen  is  influenced  by  its  bony  support,  by  the 
muscles  and  fascias  attached  to  these  bones,  and  by  the  organs  within.  In  the  upper 
portion  of  the  abdomen  the  tip  of  the  ensiform  cartilage  can  be  felt — it  is  opposite 
the  eleventh  dorsal  vertebra.  Immediately  above  the  ensiform  cartilage  is  its  junc- 
tion with  the  second  piece  of  the  sternum,  which  is  opposite  the  tenth  dorsal  verte- 
bra,— the  sixth  and  seventh  costal  cartilages  meet  at  this  point, — the  seventh,  eighth, 
ninth,  and  tenth  cartilages  can  be  followed  down  to  the  lower  border  of  the  chest  ; 
just  below  this,  one  free  rib,  the  eleventh,  can  be  distinguished  and  sometimes  in  thin 
people  the  twelfth;  but  the  twelfth  is  often  not  palpable  because  it  is  buried  beneath 
the  erector  spinae  muscles.  The  most  certain  way  of  identifying  any  particular  rib 
is  to  count  from  the  sternal  (Ludwig's)  angle,  opposite  the  second  rib. 

Below,  the  crest  of  the  ilium  can  be  followed  back  to  the  posterior  superior  spine 
of  the  ilium  and  in  front  to  the  anterior  superior  spine.  The  spines  of  the  pubes  can 
be  recognized,  as  well  as  the  upper  edge  of  the  pubic  bones.  The  depressions  for 
the  linea  alba,  linese  semilunares,  and  lineae  transversae  are  all  more  marked  above  the 
umbilicus.  The  umbilicus  lies  on  the  disk  between  the  third  and  fourth  lumbar  ver-. 
tebrse,  about  2. 5  cm.  ( i  in. )  above  a  line  joining  the  highest  points  of  the  crests  of 
the  ilia.      It  is  just  below  the  midpoint  between  the  symphysis  and  ensiform  cartilage. 

Regions. — For  clinical  purposes  the  abdomen  has  been  divided  into  regions,  so 
that  the  location  of  tumors,  signs,  etc. ,  can  be  readily  indicated.  The  most  conven- 
ient division  is  into  nine  regions  by  two  transverse  and  two  longitudinal  lines.  The 
upper  transverse  line  passes  from  the  tip  of  the  tenth  rib — which  corresponds  to  the 
lower  end  of  the  thorax — on  one  side  to  that  of  the  other.  The  lower  transverse  line 
passes  from  the  anterior  superior  spine  of  the  ilium  on  one  side  to  that  of  the  oppo- 
site ;  it  is  on  a  level  with  the  second  sacral  vertebra.  The  two  longitudinal  lines  pass 
directly  up  on  each  side  from  the  middle  of  Poupart's  ligament.  They  strike  the 
cartilages  of  the  eighth  ribs,  but  at  too  indefinite  a  point  to  serve  as  a  guide. 

The  middle  regions  are  the  epigastric,  the  umbilical,  and  the  hypogastric,  or 
pubic.  The  lateral  regions  are  the  right  and  left  hypochondriac,  the  right  and  left 
lumbar,  and  the  right  and  left  iliac. 

The  abdomen  is  sometimes  divided  into  four  quadrants  by  a  longitudinal  median 
line  and  a  transverse  line  through  the  umbilicus.  This  mode  of  division  is  used 
more  by  physicians  than  by  surgeons. 

The  lower  transverse  line  is  drawn  by  Quain  and  Cunningham  from  the  top  of 
the  crest  of  one  ilium  to  that  of  the  other,  but  as  the  umbilicus  is  often  lower  than 
usual  this  line  may  pass  above  it.  Anderson  (Morris's  "Anatomy")  suggests 
using  the  lineee  semilunares  instead  of  the  usual  longitudinal  lines,  but  as  yet  this 
modification  has  not  been  generally  accepted. 


THE  ABDOMEN. 


371 


Lines,  or  Lineae. — There  are  certain  lines  on  the  abdomen,  called  linea  alba^ 
linecB  semiiunares,  Unas  traiisversce^  and  sometimes  there  are  present  linece  albica?ites, 

Linea  Alba. — The  linea  alba  passes  in  the  median  line  from  the  ensiform 
cartilage  to  the  symphysis  pubis.  It  is  formed  by  the  fusion  of  the  sheaths  of  the 
recti  muscles.      A  little  over  half  way  down  is  the  umbilicus. 

The  linea  alba  is  broad  and  distinct  above  the  umbilicus,  separating  the  recti 
muscles  a  half  centimetre  (  \  in. )  or  more  ;  below,  it  diminishes  and  almost  or  quite 
disappears,  leaving  the  recti  muscles  almost  in  contact  with  each  other.  Its  fibres 
run  longitudinally,  obliquely,  and  transversely.  The  transverse  fibres  are  the 
strongest  and  not  infrequently  have  gaps  between  them  which  allow  the  subperitoneal 
fat  to  protrude  and  form  a  Jicrnia  in  the  median  line  which  can  be  felt  under  the  skin 
as  a  small,  firm,  rounded  body.  When  these  hernias  are  operated  on  they  are  found 
to  be  masses  of  subperitoneal  fat  with  a  somewhat  constricted  pedicle  which  emerges 


RIGHT 
MYfO- 

C^ONDRIAC 


tpie->5TRtc  ..    ^^^^    r^ 


UJMBAR 


RIGHT 
ILIAC 


Fig.  385. — Surface  anatomy  of  tne  abdomen;  lines  and  regions. 

from  a  transverse  slit  in  the  linea  alba.  The  peritoneum  is  not  protruded.  Some  o! 
the  fibres  of  the  linea  alba  are  prolonged  into  the  subcutaneous  tissue  and  skin,  thus 
binding  it  down  and  forming  a  groove  distinctly  visible  above  the  umbilicus  but  dis- 
appearing below  it.  It  does  not  long  prevent  extravasated  urine  from  passing 
from  one  side  to  the  other  (Fig.  385). 

T/ie  Ujnbiliais. — The  umbilicus  lies  over  the  disk  between  the  third  and  fourth 
lumbar  vertebrae,  and  2.5  to  4  cm.  (i  to  i  J^  in.)  above  a  line  joining  the  tops  of  the 
crests  of  the  ilia.  In  the  foetus  it  transmits  the  unibilical  vein,  the  two  nmbilical 
arteries,  and  the  remains  of  the  vitelline  duct  and  stalk  of  the  allayitois.  The 
umbilical  vein  becomes  the  round  ligament  of  the  liver  and  is  the  only  structure 
passing  into  the  upper  half  of  the  umbilicus.  The  umbilical  arteries  within  the  body 
form  the  obliterated  hypogastric  arteries,  being  continuous  with  the  superior  vesicals. 
The  vitelline  duct  in  fetal  life  passes  from  the  umbilical  vesicle  to  the  small  intestine. 


37^  -a™""  APPLIED   ANATOMY.  '^^^K^T'^CM 

Normally  it  entirely  disappears.  If  its  proximal  extremity  persists  it  forms  a  MeckeF & 
diverticiihtm,  a  projection  3  to  7  cm.  long  from  the  small  intestine  i  to  3  feet  above 
the  ileoceecal  valve.  It  may  persist  up  to  the  umbilicus  and  cause  a  fistula  through 
which  feces  may  discharge,  or  form  a  fibrous  cord  which  may  cause  a  fatal  strangula- 
tion of  the  intestine.  The  stalk  of  the  allantois  ends  as  a  fibrous  cord,  called  the 
urachus,  running  down  to  the  fundus  of  the  bladder.  If  the  urachus  remains  patu- 
lous urine  may  be  discharged  through  the  umbilicus. 

LinecB  Semilimares. — There  are  two  lineae  semilunares,  which  pass  from  the 
spines  of  the  pubes  in  a  curve  upward  and  outward  along  the  outer  edges  of  the 
recti  muscles  to  strike  the  chest  at  the  ninth  costal  cartilage.  In  thin  people  with 
litde  subcutaneous  fat  their  position  can  be  seen,  but  in  fat  people,  especially  females, 
their  location  is  not  readily  recognized.  Ordinarily  they  are  6.25  to  7.5  cm.  (2^ 
to  3  in.  )  to  the  outer  side  of  the  umbilicus  and  midway  between  the  anterior  superior 
spine  of  the  ilium  and  the  median  line.  The  fibrous  tendon  of  the  external  oblique 
muscle  passes  on  to  the  surface  of  the  rectus  muscle  to  blend  with  its  sheath  a  short 
distance  internal  to  its  lateral  border,  while  the  internal  oblique  blends  with  the  trans- 
versalis  in  the  linea  semilunaris;  so  that  an  incision  through  the  latter  would  traverse 
two  fibrous  layers — one  the  expansion  of  the  external  oblique  and  the  other  the 
blended  internal  oblique  and  transversalis.  The  upper  end  of  the  right  linea  semilu- 
naris indicates  the  position  of  the  gall-bladder.  The  point  where  a  line  from  the 
umbilicus  to  the  right  anterior  superior  iliac  spine  is  crossed  by  the  linea  semilunaris 
is  2.5  cm.  above  the  root  of  the  appendix  and  just  inside  of  McBurney's  point,  or  the 
usual  site  of  greatest  tenderness  in  appendicitis. 

LhiecB  Trmisversa;. — In  thin  muscular  people  when  the  rectus  muscle  con- 
tracts grooves  are  seen  on  its  surface  which  indicate  the  position  of  the  fibrous  lines 
called  the  lineae  transversae.  One  is  just  above  the  umbilicus,  a  second  opposite  the  tip 
of  the  ensiform  cartilage,  a  third  midway  between  these  two,  and  sometimes  a  fourth 
below  the  umbiUcus.  The  one  opposite  the  umbilicus  is  the  most  marked.  They 
are  adherent  to  the  sheath  of  the  rectus  anteriorly,  but  pass  only  part  way  through 
the  muscle,  so  that  the  rectus  muscle  can  be  lifted  off  of  the  posterior  but  not  off  of 
the  anterior  portion  of  its  sheath.     This  fact  is  to  be  remembered  in  operating. 

Linece  albicajites  are  the  faint,  white,  atrophic  lines  left  in  the  skin  of  the 
abdomen  after  it  has  been  hyperdistended,  usually  by  pregnancy  or  tumors. 

THE  POSITION  OF  THE  ABDOMINAL  VISCERA. 

Liver. —  Upper  Border. — The  highest  point  of  the  liver  is  on  the  right  side 
just  to  the  inner  side  of  the  nipple  where  it  rises  to  the  middle  of  the  fourth  inter- 
space. To  the  left  it  crosses  the  xiphosternal  articulation  to  follow  the  lower  border 
of  the  heart  to  a  little  beyond  its  apex,  but  hardly  to  the  nipple  line,  w^here  it  reaches 
the  lower  border  of  the  sixth  rib.  Its  highest  point  on  the  left  side  is  under  the  fifth 
rib  posteriorly.  On  the  right  side  it  reaches  the  upper  border  of  the  fifth  rib  in  the 
mammary  line,  the  eighth  rib  in  the  midaxillary  line,  and  the  tenth  rib  in  the  scapu- 
lar line  (Tyson,  "  Physical  Diagnosis,"  p.  51).  In  the  median  line  it  is  about  opposite 
the  tenth  thoracic  spine  (Fig.  386). 

Lower  Border. — From  just  below  and  to  the  inner  side  of  the  left  nipple  the  lower 
border  of  the  liver  passes  across  the  left  eighth  costal  cartilage,  then  across  the  median 
line  midway  between  the  xiphoid  articulation  and  the  umbilicus  to  reach  the  right  ninth 
costal  cartilage,  and  then  follows  the  edge  of  the  ribs  posteriorly.  In  the  upright  posi- 
tion, and  in  women,  the  liver  may  project  a  centimetre  or  two  below  the  edge  of  the 
chest.      In  the  aged  it  may  be  slightly  retracted. 

Liver  Dulness. — On  percussion  the  liver  dulness  in  the  right  mammary  line 
extends  from  the  upper  border  of  the  sixth  rib  to  the  lower  edge  of  the  chest.  In 
the  axillary  line  it  reaches  the  upper  border  of  the  eighth  and  in  the  scapular  line 
the  upper  border  of  the  tenth  rib.  From  these  limits  it  extends  downward  to  the 
edge  of  the  ribs. 

Gall-Bladder. — The  gall-bladder  reaches  the  surface  at  the  anterior  end  of  the 
right  ninth  costal  cartilage,  just  to  the  outer  edge  of  the  rectus  muscle.  This  is  the 
upper  end  of  the  right  linea  semilunaris. 


THE  ABDOMEN. 


373 


Stomach. — The  cardiac  end  lies  under  the  cartilage  of  the  seventh  rib,  2.5  cm. 
Cr  in.)  from  the  edge  of  the  sternum  and  about  10  cm.  (4  in.)  from  the  surface. 
When  the  stomach  is  empty  the  pylorus  lies  in  the  median  line  2.5  to  5  cm.  (i  to 
2  in.)  below  the  tip  of  the  xiphoid  or  ensiform  cartilage;  when  distended  the  pylorus 
moves  3  to  5  cm.  to  the  right.  The  fundus  rises  in  the  left  nipple  line  to  the  lower 
edge  of  the  fifth  rib.  The  lozver  border  of  the  stomach  crosses  the  median  line 
5  to  7.5  cm.  (2  to  3  in.)  above  the  umbilicus.  In  the  old  it  may  reach  as  low  as  the 
umbilicus,  and  when  dilated  may  go  far  below  it. 

Pancreas. — The  pancreas  lies  beneath  the  stomach  and  transverse  colon, 
stretching  across  from  the  duodenum  on  the  right  of  the  spine  to  the  spleen  on  the 
left.     Its  body  lies  over  the  first  and  second  lumbar  vertebrae.      This  would  brino-  its 


Fig.  386. — Surface  anatomy  of  the  aDdomen,  showing  the  outlines  of  the  viscera, 

lower  edge  about  5  cm.  (2  in.)  above  the  umbilicus  and  its  upper  edge  about  10  cm. 
(4  in.  )  above  it. 

Spleen. — The  spleen  lies  under  the  ninth,  tenth,  and  eleventh  ribs  of  the  left 
side.  Its  long  axis  follows  the  tenth  rib.  Its  anterior  end  is  at  the  midaxillary  line, 
while  its  posterior  end  reaches  to  within  4  cm.  ( i  ^  in. )  of  the  median  line. 

Kidneys. — The  lower  edge  of  the  right  kidney  reaches  to  within  an  inch  of  the 
level  of  the  umbilicus;  this  is  about  opposite  the  level  of  the  third  lumbar  spine. 
The  left  is  1,25  to  2  cm.  (^  to  ^  in. )  higher.  This  leaves  about  4  cm.  (i^  in.) 
between  the  lower  edge  of  the  kidneys  and  the  highest  point  of  the  iliac  crests. 
Their  upper  edge  is  almost  or  quite  up  to  the  level  of  the  tip  of  the  xiphoid  cartilage. 
The  pelvis  of  the  kidney  and  commencement  of  the  ureter  are  5  cm.  (2  in. )  from  the 
median  line,  about  on  the  level  of  a  line  joining  the  upper  ends  of  the  lineae  semi- 
lunares.  Posteriorly  the  right  kidney  rises  to  the  lower  border  of  the  eleventh  rib, 
the  left  kidney  to  the  upper  border.  The  outer  edge  of  the  kidney  is  a  little  beyond 
the  outer  borders  of  the  erector  spinae  and  quadratus  lumborum  muscles. 


374  '-i..  ■^•^■5U         APPLIED    ANATOMY.  ^^OS^Bm^m 

Small  Intestine. — Diiodemim. — The  duodenum  begins  at  the  pylorus  and 
curves  first  upward  and  then  downward  along  the  right  of  the  spine  to  the  body  of 
the  third  lumbar  vertebra;  it  then  crosses  and  ascends  to  the  left  side  of  the  body 
of  the  second.  This  places  it  just  above  the  umbilicus  in  the  median  line  and  behind 
the  transverse  colon. 

Mesenteyy. — The  upper  extremity  of  the  root  or  attachment  of  the  mesentery 
begins  2.5  cm.  (i  in.)  to  the  left  of  the  median  line  and  7.5  cm.  (3  in.)  above  the 
umbilicus.  It  runs  obliquely  downward  and  to  the  right  for  about  15  cm.  (6  in.) 
to  a  point  below  and  to  the  right  of  the  umbilicus,  over  the  right  sacro-iliac  joint,  and 
8  to  10  cm.  (3  to  4  in. )  above  the  middle  of  a  line  joining  the  anterior  superior  spine 
and  the  symphysis  pubis. 

Jejunum. — The  coils  of  the  jejunum  lie  mostly  to  the  left  of  the  median  line,  but 
some  are  also  found  in  the  pelvis. 

Ileum. — The  coils  of  the  ileum  lie  mostly  to  the  right  of  the  median  line,  and 
also  are  found  in  the  pelvis. 

Large  Intestine. —  Ccecum. — The  caecum  lies  in  the  right  iliac  fossa  between 
the  linea  semilunaris  and  the  anterior  iliac  spine. 

The  ileoccecal  valve  lies  8  to  10  cm.  (3  to  4  in.)  above  the  middle  of  Poupart's 
ligament. 

McBurney s  point  is  4.5  cm.  ('i^  in.)  above  and  to  the  inner  side  of  the  right 
anterior  superior  iliac  spine   on  a  line  to  the  umbilicus. 

Appendix. — The  base  of  the  appendix  is  2  cm.  (^  in.)  below  the  ileocaecal 
valve.  This  is  a  little  (i  in.)  below  the  point  where  the  linea  semilunaris  is  crossed 
by  a  line  drawn  from  the  anterior  iliac  spine  to  the  umbilicus,  and  is  opposite  the  level 
of  the  anterior  spine. 

Hepatic  Flexure  of  Colon. — This  lies  just  to  the  outer  side  of  the  gall-bladder, 
under  the  ninth  costal  cartilage. 

Transverse  Colo7i. — The  lower  edge  of  the  transverse  colon  is  about  at  the  level 
of  the  umbilicus. 

Splenic  Flexure  of  Colon. — This  rises  higher  than  the  hepatic  flexure,  about 
to  the  level  of  the  eighth  costal  interspace. 

Bladder. — When  empty  the  bladder  sinks  into  the  pelvis.  When  distended  it 
rises  toward  the  umbilicus,  carrying  the  peritoneal  fold  with  it  so  as  to  leave  a  space 
of  2. 5  to  5  cm.  ( I  to  2  in. )  between  it  and  the  top  of  the  pubis. 

Abdominal  Vessels. — The  aorta  bifurcates  on  the  body  of  the  fourth  lumbar 
vertebra  2  cm.  (3^  in.)  below  and  to  the  left  of  the  umbilicus.  A  line  from  this 
point  to  the  middle  of  one  drawn  from  the  anterior  superior  spine  to  the  symphysis 
pubis  indicates  the  course  of  the  iliac  arteries.  The  upper  third  of  this  line  is  the 
common  iliac  and  the  lower  two-thirds  the  external  iliac.  The  ureters  cross  the 
points  of  bifurcation  of  the  common  iliac  arteries.  The  coeliac  axis  lies  just  below 
the  tip  of  the  ensiform  cartilage.  The  renal  arteries  are  about  5  cm.  (2  in. )  lower. 
The  iliac  veins  lie  along  the  inner  side  of  the  iliac  arteries,  and  the  ascending  cava 
runs  along  the  right  side  of  the  aorta. 

The  deep  epigastric  arteries  run  lengthwise  at  or  a  little  outside  of  the  middle 
of  the  recti  muscles.  They  pass  beneath  the  edge  of  the  recti  a  little  below  the 
level  of  aline  joining  the  umbilicus  and  middle  of  Poupart's  ligament. 

THE   ABDOMINAL  WALLS. 

The  abdominal  walls  are  composed  of  the  skin,  superficial  fascia,  muscles,  trans- 
versalis  fascia,  subperitoneal  tissue,  and  peritoneum. 

Skin. — The  skin  of  the  abdomen  is  moderately  thin  and  lax.  It  is  adherent  at 
the  linea  alba.  In  making  incisions  care  is  to  be  taken  not  to  think  it  thicker  than 
it  is  and  so  open  the  abdominal  cavity  and  perhaps  wound  the  intestines.  This  is 
especially  liable  to  occur  in  the  median  line — where  the  subcutaneous  fat  is  not  so 
abundant  as  elsewhere — and  over  hernial  protrusions,  particularly  umbilical,  where 
the  thinned  and  distended  skin  may  lie  in  contact  with  the  peritoneum. 

Superficial  Fascia. — The  superficial  fascia  is  composed  of  an  upper  fatty 
layer,  and  a  lower  fibrous  layer  called  Scarpa' s  fascia.     The  superficial  vessels  run 


THE  ABDOMEN. 


375 


on  this  fibrous  layer  but  are  too  small  to  cause  troublesome  hemorrhage;  a  few 
minutes'  compression  with  haemostatic  forceps  serves  to  stop  bleeding  from  them. 
This  layer  is  attached  at  the  linea  alba,  but  not  sufficiently  closely  to  prevent 
extravasated  urine  from  crossing  and  reaching  both  flanks.  It  is  also  attached  to  the 
fascia  lata  just  below  Poupart's  ligament,  and  here  it  does  prevent  urine  from  passing 
downward  on  the  thigh.  It  passes  inward  over  the  spermatic  cord  and  is  continuous 
with  the  dartos  of  the  scrotum  and  its  septum.  It  is  attached  to  the  spines  of  the 
pubes  and  to  the  symphysis  in  the  median  line.  This  lea\'es  a  space  or  abdomino- 
scrotal  opening  over  the  pubic  bone  on  each  side  of  the  median  line  through  which 
extravasated  urine  rises  from  the  perineum  and  scrotum  to  reach  the  surface  of  the 
abdomen. 

MUSCLES   OF  THE   ABDOMEN. 

The  muscles  of  the  abdomen  are  arranged  in  two  distinct  groups  :  a  longi- 
tudinal group  embracing  the  recti  and  pyramidales  and  a  transverse  group  embrac- 
ing the  external  and  internal  obliqne  and  the  transversalis  of  each  side. 

The  pyramidalis  is  small,   often  undeveloped,  and  sometimes  absent  ;  as  its 


External  oblique 


Anterioi  superior  spine 
of  the  ilium 

Poupart's  ligament 
(ligamentum  inguinale) 

Intercolumnar  fibres 
Internal  pillar 

External  pillar 

Spermatic  cord 


Lineae  transversae 


Rectus  abdominis 


Sheath  of  the  rectus 
turned  back 

Umbilicus 


Pyramidalis 

External  abdominal  ring 

S^ine  of  the  pubis 


Fig.  387. — The  external  oblique,  rectus  abdominis,  and  pyramidalis  muscles. 

direction  is  not  markedly  different  from  that  of  the  rectus  it  may  be  considered  from 
a  surgical  point  of  view  as  being  a  part  of  it. 

The  rectus  muscle  arises  from  the  crest  and  symphysis  of  the  pubis  and 
inserts  into  the  cartilages  of  the  fifth,  sixth,  and  seventh  ribs  and  sometimes  the 
ensiform  cartilage  (Fig.  387). 

Sheath  of  the  Rectus. — The  rectus  muscle  is  enclosed  in  a  fibrous  sheath  formed 
by  the  external  and  internal  oblique  and  transversalis  muscles.  The  anterior  layer 
is  attached  to  the  surface  of  the  muscle  by  the  lineae  transversae  already  described 
(p.  372).  The  edge  of  the  sheath  on  one  side  blends  in  the  median  line  with  that  of 
the  other  side  to  form  the  linea  alba.  Above  the  umbilicus,  an  incision  in  the 
median  line  passes  through  fibrous  tissues  only  and  the  muscles  on  each  side  are  not 


376 


APPLIED    ANATOMY. 


exposed,  but,  as  they  rapidly  approximate  each  other  below,  an  incision  usually 
passes  either  through  the  edge  of  one  muscle  or,  if  it  passes  exactly  between  them, 
may  expose  the  edges  of  both. 

The  lateral  edge  of  the  sheath  is  formed  primarily  by  the  splitting  of  the  tendon 
of  the  internal  oblique  muscle,  one  part  going  in  front  and  the  other  behind  the 
muscle.  The  tendon  of  the  external  oblique  blends  with  the  anterior  layer  of  the 
tendon  of  the  internal  oblique  a  little  to  the  medial  side  of  the  edge  of  the  rectus, 
and  as  the  pubes  is  approached  the  external  oblique  has  its  attachment  nearer  and 
nearer  to  the  linea  alba,  so  that  close  to  the  pubes  the  external  oblique  is  separated 
from  the  internal  oblique  and  goes  to  form  the  internal  pillar  of  the  external  ring  and 
has  the  conjoined  tendon  behind  it  (Fig.  388). 

The  tendon  of  the  transversalis  blends  with  the  posterior  layer  of  the  internal 
oblique  tendon  until  the  lower  fourth  of  the  rectus  is  reached,  when  they  both  pass 
in  front  of  the  rectus  to  form  the  conjoined  tendon.      The  medial  portion  of  the 


Sheath  of  the  rectus  _ 


Rectus  abdominis 


External  oblique 
Internal  oblique 
Transversalis 


External  oblique 
Internal  oblique 
Transversalis 


Spine  of  pubis 
Crest  of  pubis 


Fig.  388. — Sheath  of  the  rectus  abdominis  muscle. 

sheath  of  the  rectus  is  attached  to  the  symphysis  and  crest  of  the  pubis  ;  its  lateral 
portion,  forming  the  conjoined  tendon,  is  attached  from  the  spine  of  the  pubis  along 
the  iliopectineal  line  for  the  distance  of  4  cm,  (i^  in.).  It  lies  behind  the  external 
abdominal  ring. 

The  lower  edge  of  the  posterior  portion  of  the  sheath  of  the  rectus  is  called  the 
semilunar  fold  of  Douglas;  the  deep  epigastric  artery  ascends  beneath  this  fold  about 
its  middle,  or  a  litde  to  its  outer  side.  From  this  arrangement  it  will  be  seen  that 
an  incision  over  or  near  the  lateral  edge  of  the  rectus  below  the  umbilicus  will  pass 
through  two  aponeurotic  layers,  viz. ,  the  external  oblique  and  the  blended  tendons 
of  the  internal  oblique  and  transversalis  (Fig.  388). 

If  it  is  desired  to  examine  the  rectus  muscle,  its  sheath  can  be  opened  at  its 
edge  and  the  muscle  lifted  up  from  the  posterior  layer,  but  it  cannot  be  detached 
from  the  anterior  layer  above  the  umbilicus  unless  dissected  loose  from  the  lineae 
transversae. 


THE  ABDOMEN. 


377 


The  external  oblique  arises  from  the  eight  lower  ribs.  Its  posterior  portion 
passes  almost  directly  downward  to  insert  into  the  anterior  half  of  the  crest  of  the 
ilium.  It  is  crossed  obliquely  by  the  anterior  margin  of  the  latissimus  dorsi  muscle 
a  short  distance  above  the  crest,  thus  leaving  a  triangular  space  between  them  called 
Petit' s  triangle  (trigonum  hanbale)  (see  page  394).  As  the  external  oblique 
approaches  the  linea  semilunaris  and  anterior  superior  spine  it  becomes  tendinous, 
its  fibres  being  nearly  but  not  quite  parallel  with  Pouparf  s  ligament.  Its  lower  edge 
forms  Poiiparf  s  ligament  (ligamentum  inguinale)  and  continues  down  on  the  thigh 
as  the  fascia  lata.  Its  inner  portion,  above  and  external  to  the  spine  of  the  pubis, 
divides  to  form  the  external  abdominal  ring  for  the  passage  of  the  spermatic  cord. 
The  outer  side  of  the  opening  is  called  the  external  pillar  or  column;  it  is  continuous 
with  Poupart's  ligament,  inserts  into  the  spine  of  the  pubis,  and  is  prolonged  along 
the  iliopectineal  line  for  a  short  distance  (2  cm.)  to  form  GiinbernaC s  ligame7it., 


Latissimus  dorsi- 

Internal  oblique 

Crest  of  ilium 
Anterior  superior  spine- 


Aponeurosis   of  external 
oblique  cut  and  turned  down 

Shelving  edge  of 
Poupart's  ligament 

Cremaster  arising  from 
Poupart's  ligament 


Attachment  of  fibres  of 
cremaster  to  the  pubis 


<v# 


..v*--' 


External  oblique  turned 
back 


Arching  fibres  of 

internal  oblique 

The  conjoined  tendon  of 

the  internal  oblique  and 

transversalis 

— Spine  of  pubis 


ti4h^%^ 


Fig.  389. — Internal  oblique  muscle. 

Sometimes  it  is  continuous  upward  and  inward  to  the  median  Jifie  on  the  sheath  of 
the  rectus,  forming  what  has  been  called  the  triangular  fascia  (CoUes).  The  inner 
side  is  called  the  internal  pillar  or  column.  It  inserts  into  the  crest  of  the  pubis. 
The  transverse  fibres  passing  from  one  pillar  or  column  to  the  other  are  called 
intercohctnnar  fibres. 

The  internal  oblique  (Fig.  389)  arises  from  the  lumbar  aponeurosis,  the  anterior 
two-thirds  of  the  crest  of  the  ilium,  and  the  outer  half  of  Poupart's  ligament.  It  inserts 
into  the  lower  three  ribs  and,  through  the  sheath  of  the  rectus  and  conjoined  ten- 
don, into  the  linea  alba,  the  crest  and  spine  of  the  pubis,  and  iliopectineal  line  for  about 
4  cm.  The  fibres  arising  from  the  lumbar  aponeurosis  and  the  posterior  portion  of  the 
iliac  crest  pass  upward  and  inward.  Those  from  the  region  of  the  anterior  superior  iliac 
spine  radiate  like  a  fan  ;  the  lower  ones,  together  with  the  fibres  arising  from  the 
outer  half  of  Poupart's  ligament,  arch  over  the  cord  and  end  in  the  conjoined  tendon. 
Some  fibres  are  continued  down  over  the  cord,  forming  the  cremaster  muscle.     The 


378 


APPLIED    ANATOMY 


cremaster  muscle  usually  arises  from  Poupart's  ligament,  beneath  the  spermatic  cord, 
from  the  lower  edge  of  the  internal  oblique  to  near  the  spine  of  the  pubes,  thus 
obliterating  the  space  usually  shown  to  the  under  side  of  the  cord,  between  it  and 
Poupart's  ligament.  The  fibres  of  the  cremaster  hang  in  loops  on  the  cord,  and  are 
attached  by  their  distal  extremity  to  the  pubic  bone  in  the  neighborhood  of  the  spine. 
The  transversalis  muscle  arises  from  the  six  lower  ribs,  through  the  lumbar 
fascia  from  the  transverse  processes  of  the  five  lumbar  vertebrae,  and  from  the  ante- 
rior two-thirds  of  the  iliac  crest  and  outer  third  of  Poupart's  ligament.  It  mserts 
through  the  sheath  of  the  rectus  in  the  linea  alba  and  crest  of  the  pubis,  and 
through  the  conjoined  tendon  into  the  spine  of  the  pubis  and  iliopectineal  line  for 
about  4  cm.  (i  ^  in.).     The  transversalis  does  not  come  down  so  low  as  the  internal 


Latissimus  dorsi 

Cut  edge  of  internal  oblique 
Transversalis 


Transversalis  fascia 

Internal  abdominal  ring 

Cremaster  muscle 

Poupart's  ligament 

Spermatic  cord 


External  oblique  cut  and 
turned  back 

Internal  oblique  turned  back 

Conjoined  tendon  of  internal 
•oblique  and  transversalis 


Rectus 


Pyramidalis 
Spine  of  pubis 
Attachment  of  cremaster 


Fig.  390. — Transversalis  muscle.. 

oblique,  because  it  arises  from  the  outer  third  of  Poupart's  ligament  instead  of  the 
outer  half,  as  does  the  internal  oblique.  As  already  stated,  the  blended  tendons  of 
the  external  and  internal  oblique  and  transversalis  muscles  all  pass  in  front  of  the 
rectus  in  its  lower  fourth.  As  the  umbilicus  is  below  the  middle  of  the  linea  alba, 
this  point,  where  the  fold  of  Douglas  is  formed,  is  nearer  to  the  umbilicus  than  it  is 
to  the  symphysis  (Fig,  390), 


VESSELS  OF  THE  ABDOMINAL   WALLS. 

The  vessels  of  the  abdominal  walls  comprise  arteries,  veins,  and  lymphatics. 
The  arteries  are  superficial  and  deep  ;  of  these  the  deep  are  the  more  important. 
The  arterial  twigs  in  the  subcutaneous  tissue  are  small.  The  superficial  epigas- 
tric runs  in  a  line  from  the  femoral  artery  toward  the  umbilicus.  The  superficial 
circumflex  iliac  runs  to  its  outer  side  toward  the  iliac  spine,  mostly  below  Poupart's 
ligament.  Branches  of  these  vessels  may  require  the  temporary  application  of  a 
haemostatic  forceps  in  the  operations  for  hernia  or  appendicitis. 

The  deep  arteries  are  important :  they  are  the  siiperior  epigastric,  deep  epi- 
gastric, and  deep  circumflex  iliac  (Fig.  391). 


THE  ABDOMEN. 


379 


The  superior  epigastric  artery  is  one  of  the  two  terminal  branches  of  the 
internal  mammary.  The  other  is  the  musculophrenic,  which  skirts  the  edge  of 
the  thorax.  The  internal  mammary  divides  opposite  the  sixth  interspace,  and  the 
superior  epigastric,  leaving  the  thorax  at  the  lower  edge  of  the  seventh  rib,  enters 
the  sheath  of  the  rectus  muscle  and  a  few  inches  lower  down  enters  the  substance 
of  the  muscle,  speedily  breaking  up  into  small  branches.  It  is  only  large  in  size 
up  toward  the  thorax,  where  we  have  seen  it  cut  by  a  stab-wound,  causing  dan- 
gerous hemorrhage.  It  may  also  be  wounded  in  operations  and  is  to  be  sought 
for  between  the  muscle  and  its  posterior  sheath,  on  a  line  continued  downward 
from  a  point  one  centimetre  to  the  outer  side  of  the  edge  of  the  sternum. 

The  deep  epigastric  artery  arises  from  the  external  iliac  at  Poupart's  liga- 
ment and  curves  inward  and  upward  between  the  peritoneum  and  transversalis 
fascia.      It  reaches  the  edge  of  the  rectus  below  a  line  joining  the  femoral   artery 


Sixth  intercostal  nerve 
Seventh  nerve 

Eighth  nerve 
Ninth  nerve 
Tenth  nerve 

Eleventh  nerve 
Twelfth  nerve 

Iliohypogastric  nerve 

Ascending  branch 

Deep  circumflex  iliac  artery 

Ilio-inguinal  nerve 


Superior  epigastric  artery 


The  sheath  of  the  rectus  has 
been  cut  along  its  outer  ed.'je 
and  the  muscle  turned  inwai'd 


Umbilicus 


Deep  epigastric  artery. 


Fig.  391. — The  nerves  and  blood-vessels  of  the  anterior  abdominal  wall.  The  nerves  are  seen  piercing  the 
posterior  layer  of  the  sheath  of  the  rectus  to  enter  the  muscle.  The  external  and  internal  oblique  have  been  removed 
exposing  the  nerves  lying  on  the  transversalis. 


at  Poupart's  ligament  with  the  umbilicus.  Opposite  the  fold  of  Douglas  (linea 
semicircularis)  it  reaches  the  middle  of  the  rectus,  pierces  the  transversalis  fascia, 
and  enters  the  substance  of  the  muscle.  It  sends  branches  to  the  outer  edge  of 
the  muscle  which  are  quite  large  and  bleed  freely  when  cut.  It  anastomoses 
above  with  the  superior  epigastric.  It  is  a  most  important  artery,  as  it  is  liable  to 
be  wounded  in  operations  for  appendicitis,  etc.  If  cut  it  will  require  a  ligature, 
and  if  pierced  by  a  needle  will  bleed  freely.  As  it  passes  upward  from  Poupart's 
ligament  it  lies  to  the  upper  and  outer  side  of  the  femoral  canal  and  may  be 
wounded  if  the  herniotomy  knife  is  turned  in  that  direction.  A  little  higher  it 
crosses  the  inguinal  canal  almost  midway  between  the  internal  and  external 
abdominal  rings.  An  oblique  inguinal  hernia  enters  the  canal  to  the  outer  side 
of  this  artery  and  a  direct  hernia  to  its  inner  side.  The  fold  of  the  obliterated 
hypogastric  artery  is  to  its  inner  side. 

The  deep  circumflex  iliac  artery  arises  from  the  external  iliac  almost  oppo- 
site the  deep  epigastric  and  passes  outward  along  the  inner  side  of  Poupart's  ligament 


38o 


APPLIED   ANATOMY. 


between  the  transversalis  fascia  and  the  peritoneum.  When  it  reaches  the  anterior'' 
superior  spine  it  passes  between  the  transversaHs  and  internal  oblique  muscles,  and 
just  above  the  crest  divides  into  an  ascending  branch  which  goes  upward  toward  the 
ribs  and  a  posterior  branch  passing  backward  to  anastomose  with  the  iliolumbar. 
The  ascending  branch  is  large  and  bleeds  freely  when  cut.  It  is  not  infrequently 
divided  in  operations  for  appendicitis  in  which  the  incision  is  carried  far  back.  Its 
depth  from  the  surface,  between  the  transversalis  and  internal  oblique  muscles, 
should  not  be  forgotten. 

Superficial  Abdominal  Veins. — The  upper  part  of  the  abdomen  is  drained 
by  small  branches  emptying  into  the  superior  epigastric,  the  intercostal,  and  laterally 
into  the  axillary  veins.  Below,  there  are  the  superficial  epigastric  and  superficial  cir- 
cumflex iliac  veins.     In  cases  of  obstruction  to  the  flow  of  blood  in  the  large  deep  veins 

the  superficial  veins  become  visible;  thus  a 
branch  often  becomes  visible  on  the  side  run- 
ning from  the  axillary  vein  to  the  superficial 
epigastric  or  femoral  vein, — it  is  called  by 
Braune  ("  Das  Venensystem  des  menschlichen 
Korpers,"  1884,  JoesselandWaldeyer,  Topog. 
chirtirg.  Anat.,  pp.  22,  147)  the  ve7ia  tho- 
racica  epigastrica  longa  tcgiimentosa  (Fig. 
392).  Other  small  veins  around  the  umbilicus 
become  very  much  enlarged,  and,  branching 
in  various  directions  around  the  umbilicus, 
have  given  rise  to  the  term  caput  Medusce. 

Kelly  ("  Operative  Gynecology,"  p.  48) 
describes  two  small  veins  running  from  the 
symphysis  up  to  the  umbilicus  in  the  subcu- 
taneous tissue  on  each  side  of  the  linea  alba, 
and  calls  them  celiotomy  vehis. 

Deep  Veins  of  the  Abdominal 
W^alls. — The  superior  epigastric,  deep  epi- 
gastric, and  circumflex  iliac  arteries  are  ac- 
companied by  veins.  There  is  also  a  vein  in 
the  round  ligament  of  the  liver  emptying  into 
the  portal  vein,  called  by  Schiff,  and  later  by 
Sappey,  the  vena pariajihilicalis  {M€rx\o\VQS  de 
I'acad.  dem^d,",  1859).  In  some  cases  two 
small  veins  can  be  seen  on  the  interior  of  the 
abdominal  wall,  running  up  to  the  umbilicus 
from  the  symphysis  on  each  side  of  the  median 
line,  and  two  coming  down  to  the  umbilicus 
on  each  side  of  the  median  line. 

Lymphatics.  —  The    superficial    parts 
above  the  umbilicus  are  drained  by  lymphatics 
which  empty  into  the  axillary  nodes;  the  ves- 
sels below  the  umbilicus  empty  into  the  oblique 
set  of  nodes  in  the  groin.      The  lymphatics  of  the  deep  surface  of  the  abdominal  wall 
above  the  umbilicus  drain  into  the  mediastinal  nodes,  while  those  below  drain  into 
the  pelvic  lymphatics  along  the  iliac  arteries. 

Nerves. — The  front  and  sides  of  the  abdomen  are  supplied  by  the  anterior  and 
lateral  cutaneous  branches  of  the  sixth,  seventh,  eighth,  ninth,  tenth,  and  eleventh  inter- 
costal nerves,  the  twelfth  thoracic  or  subcostal,  and  the  iliohypogastric  and  ilioingui- 
nal branches  of  the  first  lumbar.  The  sides  of  the  abdomen  are  supplied  by  the 
lateral  cutaneous  branches  which  supply  the  skin  as  far  forward  as  the  rectus  muscle. 
The  recti  muscles  and  skin  overlying  them  are  supplied  by  the  anterior  branches. 
These  pass  forward  between  the  internal  oblique  and  transversalis  muscles  to  enter 
the  sheath  of  the  rectus,  and,  after  supplying  the  muscle,  pierce  the  anterior  layer  and 
are  distributed  to  the  integument  above.  The  sixth  and  seventh  supply  the  infrasternal 
region,  the  eighth  about  half  way  down  to  the  umbilicus,  the  ninth  just  above  the 


Fig.  392. — Obstructinn  of  the  rik'lit  iliac  vein 
from  phlebitis.  The  vena  thoracica  epigastrica 
longa  is  seen  running  from  the  groin  up  to  the 
axilla. 


THE  ABDOMEN. 


381 


umbilicus,  the  tenth  the  region  of  the  umbiUcus,  and  the  eleventh  just  below, — 
being  about  opposite  the  fold  of  Douglas,  while  the  twelfth  supplies  the  region 
above  the  pubes. 

The  iliohypogastric  emerges  through  the  external  oblique  about  2  or  3  cm. 
above  the  external  ring,  while  the  ilio-inguinal  emerges  through  the  external  ring 
and  supplies  the  parts  adjacent.  From  this  distribution  it  is  evident  why  disease 
posteriorly,  such  as  caries  of  the  spine  or  pleurisy,  will  cause  pain  to  be  complained  of 
in  the  corresponding  distribution  anteriorly.  Incisions  through,  or  along  the  outer 
edge  of  the  rectus,  will  divide  the  nerves  supplying  it,  and  cause  paralysis  of  the 
muscle.  Incisions  made  across  the  lateral  muscles  of  the  abdomen  cannot  be 
efBciently  repaired  by  sewing  the  cut  muscles  together,  because  this  does  not  restore 
the  function  of  the  nerves  which  have  been  divided. 


ABDOMINAL   INCISIONS. 

These  are  made  through  all  portions  of  the  abdominal  walls  according  to  the 
organs  it  is  desired  to  gain  access  to.     They  should  be  so  planned  as  to  avoid  unnec- 


Kocher's,  for  bile  passages 


Battles'  incision,  for 
appendix 

McBumey's,  for  appendix 


Gastrostomy 
Gastric  ulcer,  etc. 


Oblique  incision  for  the 
kidney 


Pelvic  operations 


Pf  annenstiel  incision 


Fig.  393. — Incisions  for  abdominal  operations. 


essarily  wounding  the  muscles,  arteries,  and  nerves.  It  having  been  found  that 
incisions  through  fa^ia  alone  are  more  liable  to  be  followed  by  hernia  than  those 
through  muscles,  incisions  through  the  linea  alba  and  lineae  semilunares  are  to  be 
avoided.  Incisions  through  the  recti  muscles  are  best  made  near  their  inner  edge.  If 
made  in  the  outer  edge  the  nerves  supplying  the  muscle  will  be  divided,  causing  sub- 
sequent paralysis  and  weakness.  If  made  through  the  middle,  only  the  nerves  supply- 
ing the  inner  half  will  be  divided,  but  the  main  trunks  of  the  deep  and  superior 
epigastric  arteries  will  be  cut  and  cause  troublesome  bleeding.     There  is  least  harm 


382  APPLIED    ANATOMY. 

done  by  making  the  incision  through  the  inner  edge  of  the  muscle.  If  the  method 
of  Battles  is  resorted  to,  of  dividing  the  outer  edge  of  the  sheath  of  the  rectus  longi- 
tudinally and  displacing  the  muscle  inward,  or  of  dividing  the  muscle  itself  longitudi- 
nally, then  not  only  are  large  branches  of  the  deep  epigastric  arteries  met  but  in 
dividing  the  posterior  layer  of  the  sheath  the  nerves  are  divided.  If  the  rectus  is 
divided  transversely  (as  Kocher  advises  in  operations  on  the  gall-bladder)  care  must 
be  taken  to  avoid  wounding  the  nerves  ;  he  claims  that  the  scar  acts  only  as  an 
additional  linea  transversa  and  does  not  injure  the  functions  of  the  muscle.  Injury 
to  the  nerves  and  rectus  muscle  both  can  be  avoided  by  incising  the  sheath  transversely 
and  then  pulling  the  rectus  to  one  side  (Weir),  or  by  dissecting  up  the  sheaths  of 
both  recti  transversely  and  separating  the  muscles  in  the  median  line  (Pfannenstiel 
and  Stimson). 

Incisions  through  the  transverse  muscles  if  made  in  the  same  direction  through 
all  three  muscles  are  bound  to  cut  some  in  a  direction  more  or  less  transverse  to  their 
fibres.  The  incision  of  McBurney — for  appendicitis — avoids  wounding  the  muscles. 
He  separated  the  external  oblique  in  the  direction  of  its  fibres  downward  and  inward, 
crossing  a  line  from  the  anterior  superior  spine  to  the  umbilicus,  4  to  5  cm.  ( i  ^^  to 
2  in. )  to  the  inner  side  of  the  spine.  The  internal  oblique  and  transversalis  are  then 
separated  in  the  direction  of  the  fibres  and  drawn  in  the  opposite  direction.  This 
method  is  applicable  where  small  openings  suffice  ;  but  when  large  incisions  are  essen- 
tial, as  in  bad  suppurating  cases  of  appendicitis  and  in  operations  to  expose  the 
kidney  and  ureter,  it  is  customary  with  many  to  incise  all  the  muscles  in  the  line  of 
the  fibres  of  the  external  oblique.  Should  nerves  be  encountered  they  are  if  possible 
to  be  drawn  aside.  In  this  incision  the  internal  oblique  and  transversalis  are  incised 
nearly  transversely,  and  bleeding  from  the  deep  circumflex  iliac  artery  which  runs 
between  them  will  be  encountered. 

Edebohls  exposes  the  kidney  by  incising  alongside  of  the  outer  edge  of  the 
erector  spinae  muscle.  The  latissimus  dorsi  is  separated  in  the  direction  of  its  fibres, 
the  lumbar  aponeurosis  is  incised  and  kidney  exposed.  A  normal  kidney  can  be 
delivered  through  this  incision,  but  not  one  much  enlarged.  When  the  kidney  is 
much  enlarged  the  incision  is  to  be  prolonged  anteriorly  along  the  crest  of  the  ilium 
(see  page  396).  The  relation  of  the  pleura  is  to  be  borne  in  mind:  it  crosses  the 
twelfth  rib  about  its  middle  to  reach  its  lower  edge  posteriorly.  Hence  the  upper  end 
of  the  incision  should  always  be  kept  anterior  to  it  (see  section  on  Pleura). 

HERNIA. 

Abdominal  herniae  occur  most  often  in  the  umbilical  and  inguinal  regions. 
Sometimes  the  recti  muscles  separate  and  a  median  protrusion  results;  or  they  may 
occur  at  the  site  of  a  previous  operation. 

Umbilical  herniae  are  of  three  kinds,  congenitiil,  infantile,  and  acquired. 

Congenital  umbilical  hernia  is  due  to  a  developmental  defect.  In  the  embryo 
the  umbilicus  transmits  (i)  the  vitelline  duct,  passing  from  the  umbilical  vesicle  to 
the  small  intestines;  (2)  two  umbilical  arteries,  which  inside  the  abdomen  are  called 
hypogastric  and  pass  to  the  internal  iliacs  through  the  superior  vesicals;  (3)  one 
umbilical  vein  passing  to  the  liver  through  the  round  ligament;  (4J)  the  stalk  of 
the  allantois,  which,  on  entering  the  abdomen,  is  called  the  urachus,  and  passes 
down  to  the  bladder.  At  birth  these  structures,  with  a  myxomatous  tissue  called 
Wharton's  jelly,  are  covered  with  amniotic  tissues  and  form  the  umbilical  cord. 

If  development  is  interfered  with,  a  cleft  is  left  in  the  umbilical  region  into  which 
intestine  or  other  organs  may  protrude.  If  only  intestine  protrudes,  it  pushes 
up  into  the  umbilical  cord,  and  constitutes  a  congenital  umbilical  hernia.  If  the 
intestine  is  included  when  the  cord  is  ligated,  death  from  strangulation  will  ensue; 
hence  the  danger  of  this  form  of  herniae.  If  the  urachus  remains  patulous  it  may 
form  a  urinary  Jisttila.  The  hypogastric  arteries  become  obliterated  and,  op- 
posite Poupart's  ligament,  have  two  fossae,  one  to  their  outside  and  one  to  their 
inside.-  Into  these  fossae  direct  inguinal  herniae  may  pass.  The  persistence  of  the 
vitelline  duct  may  cause  a  finger-like  projection,  called  Meeker s  diverticulum,  on 
the  ileum,  about  2  or  3  feet  above  the  ileocaecal  valve.      Sometimes  a  band  passes 


THE  ABDOMEN. 


383 


from  Meckel's  diverticulum  to  the  umbilicus  and  causes  strangulation  of  other  coils 
of  the  intestine.  We  have  operated  on  one  such  case.  The  umbilical  vein  becomes 
obliterated  and  the  small  vein  found  in  the  round  ligament  of  adults,  called  by  Schifi 
^^&  pariimbilical,  is  a  new  formation,  and  not  the  original  fetal  umbilical  vein. 

Infantile  umbilical  hernia  is  the  common  form  which  appears  soon  after  birth. 
It  does  not  contain  omentum  so  constantly  as  does  adult  hernia,  because  it  does  not 
hang  so  low,  nor  is  it  so  well  developed. 

Acquired  umbilical  hernia  is  the  form  seen  in  adults.  The  presence  of  the 
urachus  and  hypogastric  arteries  so  strengthens  the  lower  edge  of  the  umbilical  ring 
that  hernial  protrusions  make  their  exit  above,  hence  the  hard  edge  of  the  ring  is 
nearer  the  lower  end  of  the  hernial  sac. 

These  herniae  almost  always  contain  omentum,  and  either  transverse  colon  or 
small  intestine.  The  contents  of  the  herniae  are  usually  matted  together  and 
are  adherent.  The  coverings  are  very  thin,  consisting  of  skin  and  peritoneum, 
with  a  small  amount  of  transversalis  fascia  and  scar-tissue  between.  Unless  extreme 
care  is  exercised  in  operating,  the  first  cut  will  pass  into  the  sac  and  wound  the  intes- 
tines or  omentum.  There  are  two  modes  of  operating  on  these  herniae.  In  one 
operation  the  sheaths  of  the  two  recti  muscles  are  opened  and  the  muscular  fibres  and 
sheaths  are  brought  together  and  sewed  in  the  median  line;  in  the  other,  two  flaps 


Vaginal  Funicular  Encysted 

Fig.  394. — The  various  forms  of  congenital  inguinal  hernia. 


Infantile 


are  made  from  the  fibrous  walls  of  the  sac  and  lapped  one  over  the  other,  thus  clos- 
ing the  hernial  opening  by  two  fibrous  layers.  This  may  be  done  either  longitudin- 
ally or  transversely. 

Inguinal  Hernia. — There  are  two  forms  of  inguinal  hernia,  the  congeyiital  zxiA 
the  acquired.  These  are  subdivided  into  several  varieties  which  can  only  be  under- 
stood by  having  a  knowledge  of  the  development  and  construction  of  the  parts  involved. 

Development  and  Descent  of  the  Testis. — The  testicle  originates  in  the  lumbar 
region  inside  of  the  abdomen  about  the  third  month.  It  is  behind  the  peritoneum 
and  has  a  fold  of  peritoneum,  the//zVa  vascularis,  passing  upward  from  it,  containing 
the  spermatic  artery  and  veins,  and  a  fold  passing  downward  to  the  inguinal  region 
and  into  the  scrotum  called  \k\Q.  gubernacichim.  By  the  fifth  or  sixth  month  the  testicle 
has  reached  the  abdominal  wall  at  the  internal  ring,  after  which  it  enters  the  inguinal 
canal  to  pass  into  the  scrotum  in  the  eighth  or  ninth  month  of  fetal  life.  A 
process  of  peritoneum — the  vagi?ial process — precedes  the  passage  of  the  testicle  into 
the  scrotum.  The  neck  of  the  vaginal  process  is  called  the  funicular  process.  Soon 
after  birth  the  vaginal  process  becomes  occluded,  first  at  the  internal  ring,  and  thence 
downward  until  the  testicle  is  reached,  where  the  unobliterated  portion  forms  the 
tunica  vaginalis  testis. 

Congenital  Hernice  and  Hydrocele. — There  are  several  forms  of  congenital 
herniae.  They  are  so  named,  not  because  they  exist  from  birth,  but  because  they 
are  caused  by  developmental  defects  which  exist  at  birth  (Fig.  394). 


384 


APPLIED   ANATOMY. 


The  various  kinds  of  herniae  due  to  developmental  defects  have  been  named  as 
follows:  vagifial — or  congenital^ftinicidar ,  encysted,  and  infantile. 

Vaginal  hernia  into  the  processus  vaginalis,  commonly  known  as  congenital  hernia, 
is  where  the  vaginal  process  remains  entirely  open  and  the  intestine  passes  down  to 
the  testicle.  In  this  form  the  testicle  is  found  protruding  into  and  at  the  bottom  of 
the  hernial  sac.  Fimicular  Hernia. — In  this  form  the  vaginal  process  is  occluded 
just  above  the  testicle,  but  the  funicular  process  above  remains  open  and  the  intestine 
descends  into  it.  Encysted  Hernia. — Here  the  vaginal  process  is  occluded  at  the 
internal  ring  only,  the  remainder  forming  a  continuous  sac  below  containing  the 
testicle.  When  the  intestine  descends  it  pushes  this  septum,  like  the  finger  of  a 
glove,  down  into  the  cavity  containing  the  testicle.  In  operation,  two  serous  layers 
would  be  incised,  within  one  of  which  is  the  testicle  and  within  the  other  the 
intestine.  Infantile  Hernia. — In  this  form  also  the  vaginal  process  is  occluded  only 
at  the  internal  ring.     As  the  intestine  descends  it  forms  a  sac  posterior  to  the  point 


%Jl. 


^\f.^^'^,\ 


Anterior  superior 
spine - 


-Sheath  of  rectus 


Aponeurosis  of 
external  oblique 


Poupart's  ligament 

External  pillar  of  ring 
Spermatic  cord 


-  Linea  semilunaris 

Intercolumnar  fibres 
External  abdom- 
inal ring 

Internal  pillar 
.  of  ring 


Crest  of  pubis 
Spine  of  pubis 


Fig.  39s. — Parts  concerned  in  inguinal  hernia;  the  external  abdominal  ring. 

of  occlusion  and  vaginal  process.  Thus  in  operation  three  serous  layers  are  cut 
through  in  exposing  the  intestine  and  the  sac  is  posterior  to  the  testicle. 

Hydrocele. — Hydrocele  is  an  accumulation  of  fluid  in  the  tunica  vaginalis  testis. 
It  is  usually  an  acquired  affection  of  adult  life,  and  then  does  not  appear  to  be 
dependent  on  congenital  anomalies. 

Encysted  Hydrocele  of^ihe  Cord. — This  consists  of  a  cystic  collection  in  the 
course  of  the  spermatic  cord.  It  makes  its  appearance  in  infancy  and  childhood, 
and  is  due  to  some  portion  of  the  funicular  or  vaginal  process  failing  to  become 
obliterated.  Serum  accumulates  in  this  unoccluded  portion,  forming  a  small  serous 
cyst.  Sometimes  a  small  opening  furnishes  a  communication  with  the  abdominal 
cavity,  forming  a  conge?iital  hydrocele.  In  this  case  the  contents  of  the  cyst  can  be 
pressed  back  into  the  abdominal  cavity  only  to  reappear.  Should  the  communicat- 
ing opening  become  dilated  by  a  descending  coil  of  intestine,  a  hernia  into  the  funi- 
cular process  would  be  the  result. 


.'^^v 


THE  ABDOMEN. 


38S 


Hydrocele  of  the  Canal  of  Nuck. — The  inguinal  canal  in  the  female  transmits 
the  round  ligament,  and  sometimes  a  finger-like  extension  of  the  peritoneum  resemb- 
ling the  vaginal  process  in  the  male.  Accumulation  of  fluid  may  occur  in  this  in 
the  same  manner  as  hydrocele  of  the  cord  is  formed  in  the  male.  It  is  then  called 
hydrocele  of  the  canal  of  Nuck. 

Acquired  Inguinal  Hernia. — Acquired  inguinal  herniee  maybe  either  of  the 
indirect  or  direct  kind.  To  understand  them  one  must  know^  the  construction  of 
the  inguinal  canal  and  spermatic  cord. 

Tfie  Spermatic  Cord. — As  the  testicle  descends  it  leaves  in  its  wake  the  vas 
deferois,  the  essential  part  of  the  spermatic  cord.  It  carries  with  it  the  spermatic 
artery,  from  the  aorta,  the  painpiniform  plexus  of  veins,  and  the  artery  of  the  vas 
from  the  superior  vesical.  The  vas  deferens  with  its  artery  lies  posteriorly  and  the 
spermatic  artery  and  pampiniform  plexus  are  anterior.      The  cremasteric  branch  of 


Internal  abdominal 
ring 


Shelving  edge  of 
Poupart's  ligament 


Cremaster  muscle 

covering  the 

spermatic  cord 


Sheath  of  rectus 

Aponeurosis   of   exter- 
nal oblique 

.■\rching  fibres  of  inter- 
nal oblique 

Conjoined  tendon  of 
internal  oblique  and 
transversalis 
Attachment  of  cremas- 
ter to  pubis 

-  Spine  of  pubis 


Pig.  396. — Parts  concerned  in  inguinal  hernia;  the  inguinal  canal  exposed. 

the  deep  epigastric  supplies  the  cremaster  muscle.  The  cord  also  contains  sym- 
pathetic nerves,  lymphatics,  some  fibrous  remains  of  the  vaginal  process,  and  a  few 
muscular  fibres.  These  structures  are  imbedded  in  fatty  tissue  continuous  with  the 
subperitoneal  fat  and  are  covered  by  a  fibrous  sheath  formed  by  a  continuation  of  the 
structures  of  the  abdominal  walls,  viz. ,  the  intercolumnar  fascia  from  the  external 
oblique,  the  cremasteric  fascia  from  the  internal  oblique,  and  the  transversalis  fascia. 
Inguiyial  Canal  i^Canalis  Inguinalis^. — This  runs  from  the  external  to  the 
internal  abdominal  ring  and  is  about  4  cm.  ( i  V^^  in. )  in  length.  The  exter^ial  ring 
{anmdus  inguinalis  snbciitanens^  (Fig-  395)  barely  admits  the  tip  of  the  finger  ;  it  lies 
immediately  to  the  outside  and  above  the  spine  of  the  pubis.  It  is  formed  by  a  split- 
ting of  the  fibres  of  the  external  oblique  aponeurosis  into  two  columns  or  pillars.  The 
external  colunui  {cms  inferius')  blends  with  Poupart's  ligament,  passes  beneath  the 
cord,  and  inserts  into  the  spine  of  the  pubis.     The  internal  column  (^crzis  superius') 

2S 


APPLIED    ANATOMY. 

inserts  into  the  crest  and  anterior  surface  of  the  body  of  the  pubis.  The  fibres  rui> 
ning  across  from  one  column  to  the  other  are  the  intcrcolumnar fibres  {fibrce  mter- 
criiralis^  and  are  prolonged  over  the  cord  as  the  intcrcolumnar  fascia  (Fig.  395). 

The  interfial  ?-i>ig  {a)i7i7i/us  inguinalis  abdominalis^  is  the  opening  in  the 
transversalis  fascia  where  the  cord  enters  the  canal.  It  is  1.25  to  2  cm.  (^^  to  ^  in. ) 
above  the  middle  of  Poupart's  ligament.  This  brings  it  to  the  outer  side  of  the 
external  iliac  artery. 

The  body  being  upright,  the  inguinal  canal  has  an  anterior  and  a  posterior  wall 
and  a  roof  and  floor.  The  antei'ior  wall  (nearest  to  the  skin)  is  formed  by  the 
aponeurosis  of  the  external  oblique,  and  by  the  internal  oblique  muscle  for  its  outer 
third  and  sometimes  even  its  outer  half.  The  posterior  wall  is  nearest  to  the  verte- 
bral column.      It  is  formed  by  the  transversalis  fascia  and  at  its  inner  third  the  con- 


Transversalis 


Cut  edge  of  internal 
oblique 


Internal  oblique 


Blending  of  the  layers 
with  the  sac 


Spermatic  cord 


Tunica  vaginalis 
Testicle 


Fig.  397. — The  coverings  of  an  acquired  oblique  inguinal  hernia;  from  an  actual  dissection.     The  external  and 
internal  oblique  have  been  divided  along  Poupart's  ligament  and  turned  inward  exposing  the  transversalis. 

joined  tendon.  The  roof,  nearest  to  the  head,  is  formed  by  the  arching  fibres  of  the 
internal  oblique  muscle  and — still  farther  above — the  transversalis.  The  floor  is 
nearest  to  the  feet.  The  cord  rests  on  Poupart's  ligament  with  some  of  the  fibres  of 
the  cremaster  muscle. 

To  the  inner  side  of  the  internal  ring  and  almost  midway  between  it  and  the 
external  ring  runs  the  deep  epigastric  artery,  it  is  between  the  transversalis  fascia  and 
peritoneum,  in  the  subperitoneal  fat. 

Coverings  of  an  Indirect  or  Oblique  Hernia. — As  the  intestine  descends 
to  form  an  oblique  inguinal  hernia  it  pushes  in  front  of  it  the  following  structures  : 
peritoneum,  subperitoneal  fat,  transversalis  (infundibuliform)  fascia,  internal  oblique 
muscle  (cremaster),  external  oblique  aponeurosis  (intcrcolumnar  fascia),  subcuta- 
neous tissue,  and  skin.  These  structures  are  therefore  cut  in  opening  the  sac  to 
expose  the  intestine.  The  hernia  always  descends  in  front  of  the  cord  and  testicle, 
hence  these  are  posterior.  The  site  of  strangulation  may  be  either  at  the  external 
ring  as  the  hernia  passes  through  the  external  oblique  muscle  or  at  the  internal  ring 


THE  ABDOMEN.  387 

as  it  passes  through  the  transversahs  fascia.  The  deep  epigastric  artery  is  ahvays 
along  the  inner  side  of  the  neck  of  the  sac,  therefore  division  of  the  stricture  must 
be  either  upward  or  up  and  out,  never  inward  (Fig.  397). 

Operation  for  Radical  Cure. — This  has  been  systematized  by  Bassini  of 
Padua.  The  neck  of  the  sac  having  been  exposed  by  incising  the  aponeurosis  of  the 
external  oblique,  and  the  cord  separated  from  it,  the  intestine  is  to  be  replaced  and 
the  sac  ligated  as  high  as  possible  and  cut  away.  The  cord  is  then  raised  and  the 
arching  fibres  of  the  internal  oblique  (and  transversahs)  are  sutured  beneath  it  to 
Poupart's  ligament.  The  cord  is  to  be  replaced,  and  the  cut  edges  of  the  external 
oblique  are  sewed  together  down  to  the  external  ring,  leaving  sufficient  room  for  the 
exit  of  the  cord  (Fig.  398). 

Direct  Inguinal  Hernia. — This  is  so  called  because  it  comes  directly  through 
the  abdominal  walls,  and  not  obliquely  down  through  the  inguinal  canal.  It  makes 
its  appearance  in  the  neighborhood  of  the  external  ring  (Figs.  399  and  400). 


Shelving  edge  of 
Poupart's  ligament 


Aponeurosis  of  exter 
nal  oblique  incised 
and  turned  back 

The  arching  fibres 
and  conjoined  ten- 
don of  the  internal 
oblique  and  trans- 
versalis  sewn  to  the 
edge  of  Poupart's 
ligament  under  the 
spermatic  cord 


•Spine  of  pubis 


Fig.  308. — Bassini's  operation  for  the  radical  cure  of  oblique  inguinal  hernia. 


HcsselbacJi  s  Triangle.  — Hessel bach's  triangle  is  seen  from  the  interior  of  the 
abdomen;  it  has  on  its  outer  side  the  deep  epigastric  artery,  on  its  inner  side  the 
edge  of  the  rectus  muscle,  and  as  its  base  Poupart's  ligament.  Direct  inguinal 
hernia  pierces  the  abdominal  walls  through  this  triangle.  On  looking  at  the 
abdominal  wall  from  the  inside,  five  folds  are  seen.  In  the  median  line  the  urachus 
passes  from  the  umbilicus  to  the  top  of  the  bladder;  farther  out  are  the  folds  formed 
by  the  obliterated  hypogastric  arteries  (plica  hypogastrica) ;  and  still  farther  out  the 
folds  containing  the  deep  epigastric  arteries  (plica  epigastrica).  The  fossa  between 
the  urachus  and  hypogastric  artery  is  called  the  internal  inguinal  fossa  (fovea 
supravesicalis) ;  that  between  the  hypogastric  and  deep  epigastric  arteries,  the 
middle  inguinal  fossa  (fovea  inguinalis  viedialis),  and  that  to  the  outside  of  the 
epigastric  artery  the  external  inguinal  fossa  (fovea  ingui^ialis  lateralis).  An 
indirect  or  oblique  inguinal  hernia  enters  the  abdominal  walls  at  the  external  inguinal 
fossa,  to  the  outer  side  of  the  epigastric  artery.  A  direct  hernia  almost  always  enters 
the  middle  inguinal  fossa  between  the  hypogastric  and  epigastric  arteries.  The 
hypogastric  fold  passes  up  behind  the  middle  of  the  external  ring  close  to  the  outer 


388 


APPLIED   ANATOMY. 


side  of  the  rectus  muscle.      On  this  account  a  direct  hernia  rarely  enters  to  the  inner 
side  of  the  hypogastric  fold  (Fig.  399). 

Coverings  of  a  Direct  Inguinal  Hernia. — The  conjoined  tendon  is  pro- 
longed outward  from  the  edge  of  the  rectus  muscle  two-thirds  of  the  distance  to  the 
epigastric  artery,  and  sometimes  more.     A  direct  hernia  piercing  the  abdominal  wall 


Fold  of  Douglas  (linea  semicircularis) 


Urachus 


Rectus  muscle 

Obliterated   hypogas- 
tric artery 

Deep  epigastric  artery 


Poupart's  ligament 
Vas  deferens 
External  iliac  artery. 


External  inguinal  fossa 

Middle  inguinal  fossa 

Internal  inguinal  fossa 

Fig.  399. — View  of  the  posterior  surface  of  the  abdominal  walls,  showing  the   inguinal   fossae  and  triangle  of 

Hesselbach  (the  latter  in  red). 

to  the  inside  of  the  hypogastric  artery  (very  rare)  will  push  in  front  of  it  the  peritoneum, 
subperitoneal  fat,  transversalis  fascia,  conjoined  tendon,  and  intercolumnar  fascia,  mak- 
ing its  exit  at  the  inner  side  of  the  external  abdominal  ring.  The  common  site  is  just 
to  the  outer  side  of  the  obliterated  hypogastric  artery,  and  it  pushes  in  front  of  it  the 
conjoined  tendon  and  intercolumnar  fascia,  and  makes  its  appearance  at  the  outer  side 


I 


Intercolumnar  fascia  from  the  ex. 
ternal  oblique 


•Conjoined  tendon 


Direct  inguinal  hernia 
Spine  of  pubis 
Spermatic  cord 


Fig.  400. — Direct  inguinal  hernia. 


of,  or  through,  the  external  abdominal  ring  (Fig.  400).  If  it  pierces  the  middle 
inguinal  fossa  farther  out,  and  just  to  the  inside  of  the  epigastric  artery,  it  passes  to 
the  outside  of  the  conjoined  tendon,  and  is  covered  instead  by  the  cremaster  muscle. 
Divisioyi  of  the  stricture  which  occurs  here  must  be  made  upward  and  inward, 
because  to  its  outer  side  lie  the  epigastric  vessels. 


THE  ABDOMEN. 


389 


Radical  Cure  of  Direct  Inguinal  Hernia. — When  the  conjoined  tendon  is 
sufficiently  thick  and  strono^  it  is  brought  down  and  sewed  to  Poupart's  hgament  be- 
neath and  behind  the  cord,  thus  closing  the  hernial  opening.    When  it  is  very  weak  and 


Transversalis  fascia 


Cut  edge  of  external  oblique 
Internal  oblique 


Deep  epigastric  artery 
Edge  of  rectus 

Conjoined  tendon 

Insertion  of  conjoined  tendon 
along  the  iliopectineal  line 


Spine  of  pubis 


Fig.  401. — The  conjoined  tendon  of  the  internal  oblique  and  transversalis  muscles. 

thin,  the  edge  of  the  rectus  muscle  is  dragged  downward  and  outward  and  sewed  to 
Poupart's  ligament  (Bloodgood),  then  the  conjoined  tendon  (Fig.  401)  is  brought 
down  in  front  of  it  and  sewed  to  Poupart's  ligament,  and  the  external  ring  narrowed  so 


Transversalis  fascia 


External  oblique 

Conjoine<l  tendon  of 
internal  oblique  and 
transversalis 

Rectus  muscle 
Spine  of  pubis 


Shelving  edge  of  Pou- 
part's  ligament 


Fig.  402. — Radi"al  cure  of  direct  inguinal  hernia.  The  aponeurosis  of  the  external  oblique  has  been  divided 
and  drawn  back.  The  conjoined  tendon  has  been  drawn  upward  toward  the  median  line.  The  transversalis 
fascia  covering  the  rectus  has  been  incised  and  the  edge  of  the  muscle  has  been  drawn  out  and  down  and  sewed  to 
the  edge  of  Poupart's  ligament  (Bloodgood).  The  operation  is  completed  by  sewing  the  conjoined  tendon  to 
Poupart's  ligament,  replacing  the  cord  on  it,  and  stitching  the  edges  of  the  external  oblique  together  down  to  the 
external  ring. 

as  to  allow  room  only  for  the  cord  to  escape  (Fig.  402).     (The  triangular  fascia,  page 
377,  is  too  uncertain  and  insignificant  a  structure  to  be  considered  in  inguinal  hernise). 


>90 


APPLIED    ANATOMY. 


Femoral  Hernia. — Femoral  hernia  is  always  acquired  and  descends  through 
the  femoral  canal  beneath  Poupart's  ligament  to  make  its  appearance  at  the  saphe- 
nous opening  on  the  thigh.  Beneath  the  inner  end  of  Poupart'  s  ligament  is  the 
iliopectineal  line  of  the  horizontal  ramus  of  the  pubic  bone.  The  two  form  an  angle 
with  the  spine  of  the  pubis  as  its  apex.  Gimbernat's  ligament  is  the  prolongation  of 
Poupart's  ligament  from  the  spine  of  the  pubis  for  about  2  cm.  (3/^  in.)  out  on  the 
iliopectineal  line.  From  the  iliopectineal  line  the  pectineus  muscle  proceeds  down- 
ward and  outward  beneath  Poupart's  ligament  to  below  and  behind  the  lesser  tro- 
chanter of  the  femur.  Farther  out  beneath  Poupart's  ligament  run  the  femoral  vein 
and  artery,  the  latter  being  to  the  outer  side  of  the  vein.  Between  the  femoral  vein 
and  Gimbernat's  ligament  is  left  a  space  i  to  2  cm.  (  f  to  f  in.)  wide.  This  space 
is  called  the  femoral  canal.  It  is  through  this  canal  or  opening  that  femoral  hernia 
descends.  The  femoral  sheath  is  the  continuation  downward  of  the  transversalis 
fascia  which  is  prolonged  from  the  interior  of  the  pelvis  over  the  femoral  artery  and 
vein  and  between  the  vein  and  Gimbernat's  ligament  so  as  to  form  three  compart- 
ments. The  outer  contains  the  femoral  artery,  the  middle  the  femoral  vein,  and  the 
inner  is  the  femoral  canal.     The  femoral  canal  is  from  i  to  2  cm.  (  |  to  4  in. )  long 


External  cutaneous  nerve 

Iliacus  muscle 

Anterior  crural  nerve 

Crural  branch  of  genitocrural  nerve 

Femoral  artery 

Femoral  vein 
Femoral  canal 
Gimbernat's  ligament 
Spine  of  pubis 

Pectineus  muscle 


Psoas  muscle 


Fig.  403. — The  crural  arch  and  the  structures  which  pass  beneath  it. 


/^\ 


and  runs  from  the  abdominal  side  of  Poupart's  ligament  to  the  upper  edge  of  the 
saphenous  opening  and  lies  between  the  femoral  vein  and  Gimbernat's  ligament. 
Its  lower  extremity  is  closed  by  the  meeting  of  its  sides.  Above,  or  superficial  to 
it,  is  Poupart's  ligament,  and  beneath  it  is  the  horizontal  ramus  of  the  pubis  and 
pectineal  fascia  covering  the  pectineus  muscle.  It  is  filled  with  loose  connective 
tissue,  fat,  and  lymphatics,  and  sometimes  contains  a  lymphatic  node,  forming 
all  together  what  has  been  called  the  septum  crurale.  It  will  thus  be  seen  that  the 
septum  crurale  is  continuous  with  the  subperitoneal  fatty  tissue  (Fig.  403). 

Coverings  of  a  Femoral  Hernia. — When  a  femoral  hernia  descends,  the 
intestine  pushes  in  front  of  it  the  peritoneum,  septum  crurale  (subperitoneal  tissue), 
and  the  femoral  sheath  (transversalis  fascia)  and  makes  its  appearance  at  the  saphe- 
nous opening.  The  cribriform  fascia  closing  the  saphenous  opening  gives  it  a  cover- 
ing, and  also  the  subcutaneous  tissue  and  skin  above. 

-ji>  Saphenous  Opening. — This  has  its  centre  4  cm.  ( i  ^  in. )  below  and  to  the  outer 
side  of  the  spine  of  the  pubis.  Its  margin  blends  above  with  Poupart's  ligament  to  pro- 
ceed to  the  spine  of  the  pubis.  Its  outer  and  upper  edge  is  marked,  forming  xhe  falci- 
form process  or  ligament  (of  Burns).  The  upper  inner  portion  of  the  falciform  process 
is  attached  to  the  iliopectineal  line  and  spine  of  the  pubis  and,  blending  with  Poupart's 
ligament  above,  is  called  Gimbernat\'\  ligament  {ligamenttun  lacunarc')  (Fig.  404). 


THE  ABDOxMEN. 


391 


The  part  of  the  fascia  lata  forming  the  falciform  process  thins  out  over  the 
femoral  artery  and  becomes  the  cribriform  fascia  {fascia  cribrosa)  as  it  passes  from 
the  inner  side  of  the  femoral  artery  on  to  the  femoral  vein  to  blend  with  the  pubic  fascia 


Falcifonti  process 


Superficial  circumflex 
iliac  vessels 


Femoral  artery 
Femoral  vein 

Long  saphenous  vein 
(saphena  magna) 

Internal  femora! 
cutaneous  vein 


Superficial  epigastric 
vessels 


Spine  of  pubis 
Saphenous  opening 


Superficial  external 
pudic  vessels 


Fig.  404. — The  saphenous  opening  (fossa  ovaljs). 


Deep  epigastric  artery 


Rectus  muscle 

Conjoined  tendon 

Obliterated  hypogastric 
artery 

Gimbemat's  ligament 
Spine  of  pubis 


Symphysis  pubis 


External  iliac  artery 
External  iliac  vein 
Vas  deferens 

— Femoral  canal 
Uiopectineal  line 

Obturator  vessels  and  nerves 


Fig.  405. — View  of  the  inguinal  and  femoral  regions  from  within;  the  peritoneum  has  been  removed. 

to  the  inner  side.  The  superficial  epigastric,  superficial  circumflex  iliac,  and  super- 
ficial external  pudic  arteries  and  veins  all  pierce  this  cribriform  fascia,  as  do  also  the 
superficial  lymphatics  and  the  long  or  internal  saphenous  vein. 


392 


APPLIED   ANATOMY. 


Point  of  Sh'angidation.-^k%  a  femoral  hernia  descends  it  may  be  strangulated 
on  the  sharp  edge  of  Gimbernat's  ligament  or  at  the  upper  portion  of  the  falciform 
process  (Fig.  404). 

Division  of  Stricture. — If  Gimbernat's  ligament  is  the  constricting  band  the 
incision  is  to  be  made  in  an  upward  and  inward  direction.  If  the  upper  portion  of 
the  falciform  process  is  the  constricting  part  the  incision  should  be  made  directly 
upward  into  Poupart's  ligament. 

In  order  to  avoid  wounding  an  anomalous  obturator  artery  which  may  wind 
around  the  neck  of  the  sac,  the  stricture  is  best  cut  from  without  inward. 

Radical  Cure  of  Femoral  Hernia. — The  intestine  and  omentum  having 
been  replaced,  the  neck  of  the  sac  is  ligated  as  high  up  as  possible  and  cut  away  or, 
preferably,  the  two  ends  of  the  ligature  are  brought  up  through  the  aponeurosis  of 
the  external  oblique  and  tied  on  its  surface  just  above  Poupart's  ligament.  To  close 
the  femoral  canal  two  or  three  sutures  are  inserted  as  follows:  If  the  hernia  is  on  the 
right  side,  the  needle  is  passed  downward  through  the  inner  end  of  Poupart's  liga- 
ment, close  to  the  spine  of  the  pubis,  into  the  pectineal  or  pubic  portion  of  the 
fascia  lata,  and  brought  out  alongside  of  the  femoral  vein.  It  is  then  inserted  again 
through  the  edge  of  the  falciform  process  and  the  suture  tied,  thus  pulling  the  falci- 


IHac  portion  of  fascia  lata 
Falciform  process 

Pubic  portion  of  fascia  lata 


Poupart's  ligament 


Fascia  over  the  pectineus  muscle 


Fig.  406. — Operation  for  the  radical  cure  of  femoral  hernia. 

form  process  and  the  lower  edge  of  Poupart's  ligament  down  on  the  fascia  covering 
the  pectineal  muscle.  Two  or  three  sutures  are  all  that  are  required.  Another  way 
of  inserting  the  sutures  is  longitudinally,  instead  of  transversely.  The  first  would  be 
close  in  to  Gimbernat's  ligament,  the  second  a  little  farther  out,  and  the  third  as 
close  to  the  femoral  vein  as  possible  (Fig.  406), 


THE   LUMBAR   REGION. 

This  region  is  at  times  affected  with  abscesses  or  hernial  protrusions  and 
through  it  incisions  are  made  to  reach  the  kidney  (Fig.  407). 

Muscles. — The  quadratus  lumborum  muscle  arises  from  the  transverse 
processes  of  the  lower  four  lumbar  vertebrae,  the  iliolumbar  ligament,  and  5  cm.  (2  in.) 
of  the  iliac  crest.  It  inserts  into  the  posterior  half  of  the  last  rib  and  transverse 
processes  of  the  upper  four  lumbar  vertebrae.  The  erector  spinae  is  the  muscular 
mass  which  fills  the  groove  to  the  outer  side  of  the  spinous  processes.  It  arises 
from  the  spines  of  the  lumbar  vertebrae,  the  back  of  the  sacrum,  the  sacrosciatic  and 
sacroiliac  ligaments,  and  about  the  posterior  fourth  of  the  crest  of  the  ilium.  It 
inserts  into  the  posterior  portion  of  the  vertebrae  and  ribs  above.  The  latissimus 
dorsi  arises  from  the  spinous  processes  of  the  lower  six  thoracic  vertebrae  and  the 
vertebral  aponeurosis,  which  is  attached  to  the  spinous  processes  of  the  lumbar 
vertebrae,  the  posterior  surface  of  the  sacrum,  and  the  posterior  third  of  the  crest  of 


THE  ABDOMEN.  393 

the  ilium.  It  passes  upward  and  forward  to  insert  into  the  inner  lip  of  the  bicipital 
groove  of  the  humerus. 

It  will  thus  be  seen  that  while  the  direction  of  the  outer  fibres  of  the  latissimus 
dorsi  is  from  below  upward  and  forward,  the  direction  of  those  of  the  quadratus 
lumborum  is  upward  and  backward.  It  will  also  be  observed  that  the  attachment 
of  the  quadratus  lumborum  is  farther  out  on  the  crest  of  the  ilium  than  is  that 
of  the  latissimus  dorsi,  reaching"  about  its  middle  (Figs.  408,  409  and  410). 

Fascias. — The  lumbar  fascia  (fascia  lumbodorsalis),  so  called,  is  the 
continuation  backward  of  the  posterior  aponeurosis  of  the  transversalis  and  internal 
oblique  muscles  to  the  spine.  When  the  aponeurosis,  from  which  these  two  muscles 
spring,  reaches  the  outer  edge  of  the  quadratus  lumborum,  it  splits;  one  thin  layer 
goes  on  its  ^'entral  surface  to  be  attached  to  the  roots  of  the  transverse  processes  of 
the  vertebrje;  the  other  thick  posterior  layer,  on  reaching  the  edge  of  the  erector 


Latissimus  dorsi 


External  oblique 


Petit's  triangle  and 
internal  oblique 


Sacrospinalis  (erector 
spinas) 


Fig.  407. — The  lumbar  region,  superficial  view. 

spinae  muscles  divides  into  two,  the  anterior  of  which  covers  the  dorsal  surface  of  the 
quadratus  lumborum  and  the  ventral  surface  of  the  erector  spinae  to  attach  itself  to 
the  tips  of  the  transverse  processes,  while  the  posterior  layer  passes  over  the  dorsal 
surface  of  the  erector  spinae  to  be  attached  to  the  spinous  processes  of  the  lumbar 
vertebrae.  These  three  layers  are  called  the  anterior,  middle,  and  posterior  layers 
of  the  lumbar  fascia  (see  Fig.  410). 

The  anterior  layer  is  attached  to  the  tip  of  the  twelfth  rib  and  arches  inward  to 
the  transverse  process  of  the  first  or  second  lumbar  vertebra,  to  form  the  external 
arcuate  ligament  of  the  diaphragm.  It  is  practically  continuous  with  the  transver- 
salis fascia. 

The  middle  layer  is  attached  above  to  the  last  rib,  and  below  to  the  iliac  crest, 
and  is  \'ery  strong. 

The  posterior  layer  is  continuous  above  with  the  vertebral  aponeurosis  and  gives 
origin  to  the  latissimus  dorsi  muscle. 


394 


APPLIED    ANATOMY. 


Petit's  Triangle  (trigonum  lumbale). — Above  the  middle  of  the  crest  of 
the  ilium  is  a  small  triangular  space  formed  by  the  edge  of  the  external  oblique  in 
front,  of  the  latissimus  dorsi  behind,  and  the  crest  of  the  ilium  below.  Its  f^oor  is 
formed  by  the  internal  oblique  muscle,  and  it  is  called  the  triangle  of  Petit.  It  forms 
a  weak  point  in  this  region  through  which  collections  of  pus  or,  more  rarely,  ventral 
herniie,  may  make  their  appearance  (Fig.  407). 

Fascial  Triangle.  — h  bove  and  a  little  posterior  to  Petit' s  triangle  is  another 
triangular  space.  Its  base  is  the  twelfth  rib,  its  anterior  side  is  the  posterior  edge 
of  the  internal  oblique,  and  posterior  side  is  the  outer  edge  of  the  quadratus  lum- 
borum.  It  is  also  called  the  triangle  of  Grynfelt  and  Lesshaft.  The  lower  portion 
of  the  kidney  lies  immediately  beneath  it  and  the  latissimus  dorsi  covers  it  (Figs. 
408  and  409). 


Serratus  posticus  inferior 


Latissimus  dorsi 


Eleventh  rib 
liohypogastric  nerve 
lio-inguinal  nerve 

Fascial  triangle  and 
kidney  beneath 

Internal  oblique 
Iliohypogastric  nerve 


Fig.  408. — The  lumbar  region;  the  latissimus  dorsi  has  been  turned  back  and  the  external  oblique  cut  away,  reveal- 
ing the  fascial  triangle. 


Lumbar  Abscess. — Pus  in  the  lumbar  region  usually  originates  from  caries  of 
the  vertebrae,  from  calculus  or  other  renal  or  perirenal  affections,  or,  if  on  the  right 
side,  sometimes  from  disease  of  the  appendix.  Empyemas  may  likewise  point  in  this 
region.  Pus  starting  from  the  vertebrae  may  push  its  way  outward  under  the 
transversalis  aponeurosis  (anterior  layer  of  the  lumbar  fascia)  and  perforate  the  trans- 
versalis  muscle  where  the  iliohypogastric,  ilio-inguinal,  and  last  thoracic  nerves  enter 
and  thus  reach  the  under  surface  of  the  internal  oblique  and  perforate  this  muscle  to 
find  its  exit  at  Petit's  triangle.  Pus  may  also  perforate  the  floor  of  the  fascial 
triangle  and  follow  the  anterior  surface  of  the  latissimus  dorsi  down  until  it  points  in 
the  angle  between  the  posterior  portion  of  the  crest  of  the  ilium  and  the  spine.  The 
quadratus  lumborum  muscle  is  thin,  and  its  outer  edge,  which  is  not  covered  by 
the  erector  spinae  muscle,  is  readily  pierced  by  pus.  The  erector  spince  is  a  thick 
muscle  covered  both  anteriorly  and  posteriorly  by  the  thick  middle  and  posterior 
layers  of  the  lumbar  fascia,  hence  pus  does  not  pierce  it  but  always  goes  around  its 
outer  side. 

Lumbar  hernia  usually  results  from  the  giving  way  of  a  scar  from  an  operation. 


THE  ABDOMEN. 


395 


Lumbar  incisions  are  made  to  evacuate  pus  or  to  operate  on  the  kidney. 
Incisions  to  evacuate  pus  sliould  be  made  obliquely  from  the  outer  edge  of  the 
quadratus  lumborum  in  order  to  avoid  wounding  the  nerxes. 


Serratus  posticus 
inferior 


Latissimus  dorsi 


Quadratus  lumborum 


Eleventh  rib 


Kidney 

.Capsule  of  ikidney 

Fascia  of -internal 

blique  and 
transversalis 

Iliohypogastric  nerve 

Ilio-inguinal  nerve 


Fatty  tissue  below 
the  ladney 


Fig.  409. — Lumbar  region,  showing  the  kidney  and  quadratus  lumborum  muscle  exposed. 


First  lumbar  vertebra 


Mass  of  erector  spiuje  muscles        / 
Vertebral  aponeurosis 
Middle  layer  of  lumbar  fascia 
Posterior  layer  of  lumbar  fascia 


Perirenal  fat 


Kidney 


Quadratus  lumborum 
Anterior  layer  of  lumbar  fascia 


Transversalis 
Internal  oblique 


—External  oblique 


Latissimus  dorsi 
Fir,.   410. — Transverse  section  of  the  lumbar  region,  showing  the  lumbar  fascias  and  muscles. 

Longitudinal  Incision. — If  it  is  desired  to  expose  the  kidney,  a  straight  incision 
10  cm.  (4  in.)  long  may  be  made  between  the  last  rib  and  middle  of  the  crest  of 
the  ilium  along  the  outer  edge  of  the  quadratus  lumborum.  This  may  sometimes 
•necessitate  cutting  the  last  thoracic  nerve  near  the  rib  and  the  iliohypogastric  and 


396  APPLIED   ANATOMY. 

ilio-inguinal  nerves  near  the  crest.  They  should  if  possible  be  pulled  aside,  but  ii 
cut  are  to  be  stitched  together  again.  This  gives  only  sufficient  room  to  bring 
a  normal-sized  kidney  out  of  the  wound;  if  the  kidney  is  enlarged,  Edebohls  recom- 
mends prolonging  the  incision  along  the  crest  of  the  ilium.  This  longitudinal 
incision  lies  just  back  of  the  external  oblique,  traverses  in  its  upper  part  the  latissi- 
mus  dorsi  (the  fibres  of  which  may  be  parted  by  blunt  dissection)  then  the  lumbar 
fascia  or  anterior  edge  of  the  quadratus  lumborum  muscle,  and  lastly  the  transversa- 
lis  fascia  behind  the  peritoneum  (Fig.  411). 

Oblique  Incision. — When  an  incision  for  enlarged  kidneys,  tumors,  or  abscesses 
is  desired,  it  can  be  made  obliquely  downward  and  forward  from  the  twelfth  rib — 
anterior  to  its  middle — toward  the  anterior  portion  of  the  crest  of  the  ilium.  This 
parts  the  fibres  of  the  external  oblique  and  divides  the  fibres  of  the  transversalis 
muscle  obliquely,  and  those  of  the  internal  oblique  almost  transversely,  but  the 
nerves  (twelfth  thoracic  and  iliohypogastric)  are  more  readily  drawn  aside  than  if  the 
longitudinal  incision  is  used.     Care  is  to  be  taken  not  to  go  farther  back  than  the 


Twelfth  rib 

Latissimus  dorsi 

Lumbar  fascia 

Quadratus  lumborum  


Vertebral  aponeurosis 


^^^^^^^^^  Transversalis 

Erector  spina; 

Internal  oblique 

External  oblique 


Fig.  411. — Lumbar  incisions  for  operations  on  the  kidney,  showing  the  direction  of  the  muscular  fibres. 

middle  of  the  twelfth  rib,  because  the  pleura  usually  crosses  at  that  point  to  reach 
the  lower  edge  of  the  rib,  or  even  a  little  below  it  at  its  posterior  extremity.  As 
it  is  sometimes  difficult  to  identify  the  twelfth  rib,  because  it  may  be  so  short  as  to 
be  hidden  beneath  the  muscles,  the  most  certain  way  is  to  count  downward  from 
the  angle  of  the  sternum  opposite  the  second  costal  cartilage.  There  may  be  some 
bleeding  at  the  lower  portion  of  the  wound  from  the  ascending  branch  of  the  deep 
circumflex  iliac  artery  near  the  anterior  portion  of  the  crest  of  the  ilium. 

THE  INTERIOR   OF  THE  ABDOMEN. 

The  abdominal  cavity  extends  only  to  the  brim  of  the  pelvis;  the  pelvic  cavity 
is  separate.  The  peritoneal  cavity  is  not  synonymous  with  the  abdominal  cavity: 
some  of  the  abdominal  organs  project  comparatively  little  forward  into  it  and,  as 
in  the  case  of  the  kidneys,  may  be  only  partly  covered  with  the  peritoneum.  The 
peritoneal  cavity  includes  the  pelvis,  so  that  an  infection  of  the  pelvic  peritoneuni 
of  necessity  involves  a  part  of  the  general  peritoneal  cavity. 

The  peritoneum  is  a  closed  sac  lining  the  abdomen  and  pelvis  into  which  the 


THE  ABDOMEN. 


397 


various  abdominal  and  pelvic  organs  grow.  As  the  organs  increase  in  size  they  push 
farther  into  the  abdominal  cavity  and  the  peritoneum  covers  more  of  their  surface, 
until  in  some  cases  the  two  layers  (anterior  and  posterior)  meet;  thus  the  organ  is 
left  hanging  by  its  peritoneal  pedicle.  The  peritoneum  covering  the  organs  is  called 
the  visceral  peritoneum,  that  lining  the  walls  of  the  abdominal  cavity  the  parietal 
peritoneum.  Those  parts  of  the  peritoneum  joining  the  visceral  and  parietal  layers 
receive  various  names.  Sometimes  they  are  called  ligaments, — thus  we  have  the 
various  ligaments  of  the  liver,  the  coronary,  lateral,  and  suspensory  ;  of  the  spleen  ; 
of  the  uterus;  bladder,  etc.  Sometimes  they  are  called  omenta, — thus  we  have  the 
greater  omentum,  the  lesser  or  gastrohepatic  omentum  and  the  gastrosplenic  omen- 
tum. Sometimes  they  receive  the  name  of  mesentery,  which  is  applied  to  the  small 
intestine,  and  mesocolon,  as  applied   to  the  large  intestine.      From  this  arrangement 


Coronary  ligament 


Liver 

Lesser  omentum 

Foramen  of  Winslow 

Stomach  (pyloric  end) 

Pancreas 

Lesser  peritoneal  cavity 

Transverse  mesocolon 

Third  part  of  duodenum 
Transverse  colon 
Great  omentum 
—  Mesentery 

Small  intestine 

Greater  peritoneal  cavity 


Vesico-uterine  pouch 


Recto- uterine  pouch  or  pouch  of  Douglas 


Fig.  412. — Anteroposterior  section,  showing  the  peritoneum. 


it  is  evident  that  there  is  some  portion  of  every  abdominal  and  pelvic  organ  that  is 
not  covered  by  peritoneum.  In  some  organs,  as  the  small  intestines,  the  uncovered 
part  is  very  small,  being  at  the  attachment  of  the  mesentery.  In  other  organs,  as 
the  kidneys,  it  is  very  large,  embracing  all  their  posterior  surface.  In  operating  on 
the  abdominal  or  pelvic  organs  these  attachments  are  of  importance,  as  a  knowledge 
of  them  enables  the  surgeon — for  example,  in  operating  on  the  kidney  for  renal  cal- 
culus— to  complete  his  procedures  without  wounding  the  peritoneum  or  opening  the 
peritoneal  cavity.  The  upper  and  lower  limits  of  the  peritoneum  are  also  important, 
as  it  is  liable  to  be  wounded  in  operations  on  the  chest  and  the  organs  of  the  pelvis. 

A  knowledge  of  the  course  pursued  by  the  peritoneum  over  the  various  organs 
is  of  service  both  in  diagnosis  and  operative  procedures. 

Vieiving  the  body  in  an  anteropostej'ior  section  (Fig.  412),  and  beginning  at  the 
umbilicus,  the  peritoneum  is  seen  to  pass  upward  on  the  posterior  surface  of  the  anterior 
abdominal  wall  until  it  reaches  the  under  surface  of  the  diaphragm,  which  it  covers, 
to  the  upper  posterior  surface  of  the  liver,  where  it  forms  the  coronary  ligament  on 


398 


APPLIED   ANATOMY. 


the  right  side  and  the  left  lateral  ligament  on  the  left.  It  then  covers  the  upper  or 
parietal  surface  of  the  liver  and  curves  around  the  anterior  edge  and  the  under 
or  visceral  surface  as  far  as  the  transverse  fissure.  Thence  it  proceeds  to  the  stom- 
ach, forming  the  anterior  layer  of  the  lesser  or  gastrohepatic  omentum.  After 
covering  the  anterior  wall  of  the  stomach,  it  leaves  the  greater  curvature  to  form  the 
anterior  layer  of  the  greater  omentum.  It  next  passes  to  the  transverse  colon,  which 
it  covers  and  passes  back  to  the  spine  at  the  lower  border  of  the  pancreas.  It  then 
goes  downward,  covering  the  transverse  portion  of  the  duodenum  and  forming  the 
anterior  layer  of  the  mesentery.  Having  covered  the  small  intestine,  it  goes  back 
to  the  spine,  forming  the  posterior  layer  of  the  mesentery,  and  descends  until  it 
reaches  the  rectum.  From  the  rectum  it  is  reflected  forward  to  the  upper  part  of 
the  vagina  and  uterus  in  the  female,  forming  the  recto-uterine  pouch  (or  pouch  of 
Douglas')  or  on  the  bladder  in  the  male,  being  at  this  point  about  7.5  cm.  (3  in.) 
distant  from  the  anus.  After  covering  the  fundus  and  body  of  the  uterus,  it  is 
reflected  at  the  level  of  the  internal  os  to  the  bladder,  forming  the  uterovesical 
fold.  From  the  top  of  the  bladder  it  passes  up  the  abdominal  wall  to  reach  the 
umbilicus. 

The  peritoneum  lining  the  lesser  cavity  can  be  followed  upward  from  the  anterior 
surface  to  the  pancreas.  It  ascends  on  the  posterior  abdominal  wall  to  the  under 
surface  of  the  liver,  forming  the  under  layer  of  the  coronary  and  left  lateral  ligaments. 


Right  kidney 

Foramen  of  Winslow 

Portal  vein 

Common  bile  duct 


Hepatic  artery 
Gastrohepatic  omentum' 


Vena  cava 

Aorta 

Left  kidney 
Pancreas 


Lienorenal  ligament 
-  Spleen 

Lesser  peritoneal  cavity 
Gastrosplenic  omentum 


Stomach 
Greater  peritoneal  cavity 


Round  ligament 

Falciform  ligament 

Fig.  413. — Transverse  section  made  through  the  foramen  of  Winslow.     (Viewed  fiom  above.) 


and  at  the  transverse  fissure  is  reflected  to  the  posterior  surface  of  the  stomach, 
forming  in  its  course  the  posterior  layer  of  the  gastrohepatic  omentum.  From  the 
greater  curvature  it  passes  downward  and  then  upward  to  the  colon,  forming  the 
posterior  layer  of  the  greater  omentum.  From  the  posterior  edge  of  the  transverse 
colon  it  passes  to  the  anterior  surface  of  the  pancreas,  having  in  its  course  formed 
the  upper  (cephalad)  layer  of  the  transverse  mesocolon. 

Viewhig  the  body  iji  transverse  section. — On  examining  a  transverse  section 
made  below  the  foramen  of  Winslow,  the  peritoneum  is  seen  conjing  from  the 
parietes  and  passing  over  the  ascending  colon,  leaving  its  posterior  surface  uncovered. 
Thence  it  passes  over  the  vena  cava  and  spine,  to  go  to  the  mesentery  and  small 
intestines.  Returning  to  the  spine,  it  passes  over  the  aorta,  and  out  over  the 
descending  colon,  usually  leaving  a  portion  of  its  posterior  surface  uncovered. 
Thence  it  returns  to  the  anterior  parietes. 

In  a  section  made  passing  through  the  foramen  of  Winslow  (Fig.  413),  the  mode 
of  formation  of  the  lesser  cavity  of  the  peritoneum  and  the  relation  of  the  peritoneum 
to  the  stomach,  spleen,  and  kidneys  will  be  more  readily  understood.  Beginning 
on  the  anterior  abdominal  wall,  at  the  median  line  and  proceeding  to  the  right,  the 
peritoneum  is  seen  to  enclose  the  round  ligament  of  the  liver,  forming  a  mesentery 
for  it  named  the  falciform  ligament.  Continuing  around,  the  peritoneum  lines  the 
inner  surface  of  the  anterior  and  lateral  abdominal  walls,  covers  the  anterior  surface 
of  the  right  kidney,  and,  after  forming  the  posterior  wall  of  the  foramen  of  Winslow, 
covers  the  vena  cava,  aorta,  spine,  and  pancreas;  it  then  passes  over  the  left  kidney 


THE    ABDOMINAL   VISCERA.  399 

to  go  to  the  spleen,  forming  the  anterior  layer  of  the  lienorenal  ligament.  It  is  then 
reflected  from  the  spleen  to  the  posterior  surface  of  the  stomach,  forming  the 
posterior  layer  of  the  gastrosplenic  omentum.  From  thence  it  passes  forward  on 
the  stomach,  past  the  pylorus  to  the  upper  surface  of  the  first  portion  of  the  duode- 
num. Here  it  winds  around  the  hepatic  artery,  portal  vein,  and  common  bile  duct 
to  reach  the  anterior  surface  of  the  stomach.  This  reflection  forms  the  free  anterior 
edge  of  the  foramen  of  Winslow.  From  the  fundus  of  the  stomach  it  passes  to  the 
spleen,  forming  the  anterior  layer  of  the  gastrosplenic  omentum.  It  winds  around 
the  outer  or  costal  surface,  and  the  inner  or  renal  surface  of  the  spleen,  and  thence 
passes  to  the  left  kidney,  forming  the  posterior  layer  of  the  lienorenal  ligament. 
After  covering  the  outer  portion  of  the  kidney,  it  is  reflected  to  the  abdominal  wall 
which  it  follows  to  the  median  line. 

The  Transversalis  Fascia. — Superficial  to  the  peritoneum  and  between  it  and 
the  structures  which  it  covers  is  a  layer  of  fibrous  tissue  which  varies  in  thickness. 
The  part  which  lines  the  muscles  of  the  abdomen  is  called  the  transversalis  fascia. 
It  is  thickest  and  most  marked  in  the  lower  portion  of  the  abdomen  and  accom- 
panies the  femoral  vessels  down  the  thigh. 

Subperitoneal  Fat. — In  certain  locations  there  is  more  or  less  fatty  tissue 
between  the  transversalis  fascia  and  the  peritoneum,  and  sometimes  it  is  impossible 
to  differentiate  them.  They  blend  in  the  region  of  the  kidneys,  the  mesenteries, 
inguinal  regions,  etc.  In  the  femoral  canal  the  transversalis  fascia  is  continuous  with 
the  sheath  of  the  vessels  and  the  subperitoneal  fat  with  the  septum  crurale.  The 
protrusion  of  this  subperitoneal  fat  in  the  median  line  usually  above  the  umbilicus 
forms  the  fatty  herniae  alluded  to  on  page  371. 

THE  ABDOMINAL  VISCERA. 

The  abdominal  contents  should  first  be  studied  as  to  their  positions  and  general 
relations,  so  that  they  can  be  readily  found  and  identified,  and  then  studied  as  to 
their  intimate  relations  to  the  immediate  surrounding  structures. 

By  knowing  the  first,  an  operator  is  enabled  to  expose  quickly  the  aflected  part, 
and  by  knowing  the  second  he  is  enabled  to  carry  out  the  desired  procedures. 
While  it  is  true  that  the  presence  of  tumors  or  enlargement  of  the  various  organs 
may  distort  and  displace  them  and  so  render  their  exposure  and  recognition  difficult, 
nevertheless  a  knowledge  of  the  normal  relations  is  essential  in  order  to  solve  the 
difftculties  which  arise  in  operating  for  or  studying  the  various  abdominal  diseases 
and  injuries. 

It  must  be  borne  in  mind  that  the  extent  and  position  of  the  various  organs  is 
not  always  the  same,  even  though  they  are  not  diseased;  it  is  easier  to  find  a 
distended  than  a  contracted  stomach;  in  some  people  the  liver  though  not  diseased 
may  be  lower  than  in  others,  etc. 

When  the  abdominal  cavity  is  freely  opened  the  general  relation  of  the  organs 
is  visible  as  in  Fig.  414.  In  the  upper  portion  is  seen  the  liver.  Its  edge  usually  is 
inclined  upward  toward  the  left,  but  sometimes  it  passes  alm.ost  transversely  across. 
In  the  male  its  lower  edge  should  be  about  even  with  the  lower  edge  of  the  thorax 
(tenth  rib)  but  in  females  it  may  be  a  finger-breadth  lower.  Its  anterior  edge  is 
marked  by  the  gall-badder  and  round  ligamejit.  The  gall-bladder  is  liable  to  be  a  little 
to  the  outside  of  its  normal  position  at  the  upper  extremity  of  the  right  linea  semi- 
lunaris. The  round  ligament  reaches  the  liver  not  at  the  median  line  but  2.5  to  4 
cm.  (i  to  xy-z  in.)  to  its  right.  The  point  at  which  the  liver  crosses  the  median 
line  is  approximately  4  cm.,  (i^  in.)  below  the  tip  of  the  ensiform  cartilage.  The 
stomach  is  seen  to  the  left  of  the  liver,  between  it  and  the  left  costal  cartilages. 
Frequently  the  stomach  is  seen  to  pass  a  little  to  the  right  of  the  median  line,  partic- 
ularly if  it  is  distended.  A  small  portion  only,  2.5  to  4  cm.  (i  to  i>^  in. ),  is  seen  in 
the  median  line  and  its  lower  border  slopes  up  and  to  the  left  to  disappear  under  the 
edge  of  the  ribs.  Immediately  below  the  stomach  lies  the  transverse  colon,  concealed 
beneath  omentum.  The  omoiticm  hangs  down  from  the  lower  edge  of  the  stomach 
and  spreads  over  almost  the  whole  of  the  abdomen  below.       It  is  almost  always 


400 


APPLIED   ANATOMY. 


encountered  in  operating  for  appendicitis  and  is  often  found  in  a  hernia.  The  gall- 
bladder is  almost  the  only  organ  below  the  liver  and  stomach  which  it  is  not  liable  to 
cover.  Not  infrequently  the  omentum  is  not  found  spread  out,  but  from  the  move- 
ments of  the  intestines  it  may  lie  between  their  coils  or  be  displaced  largely  to  the 
left.  The  transverse  colon  passes  upward  and  to  the  left ;  it  crosses  the  median  line 
just  below  the  stomach  and  may  reach  as  low  as  the  umbilicus.  Not  infrequently, 
however,  there  may  be  a  coil  of  small  intestine  between  the  level  of  the  umbilicus 


Fig.  414. — ^View  of  the  abdominal  organs  in  situ.  Beneath  the  ensiform  process  is  seen  the  liver  with  the 
round  ligament  to  the  right  of  the  median  line,  below  come  the  stomach,  then  the  transverse  colon,  and  lower  down 
the  small  intestines,  over  which  is  spread  the  great  omentum.  In  the  right  iliac  region  is  seen  the  ascending  colon 
and  in  the  left  the  termination  of  the  descending  colon. 


and  the  transverse  colon,  or  a  coil  may  even  push  the  transverse  mesocolon  in  front 
of  it  and  show  itself  between  the  stomach  above  and  the  transverse  colon  below. 

The  ccecuni  and  the  commencement  of  the  ascending  colon  are  almost  always 
seen  superficially  in  the  right  iliac  fossa.  The  lower  end  of  the  Ccccum  may  reach 
as  far  forward  as  the  middle  of  the  inguinal  (Poupart's)  ligament,  but  when  the 
ascending  colon  reaches  the  upper  edge  of  the  iliac  crest  it  sinks  backward  out  of 


THE   STOMACH. 


401 


sight,  to  reappear  again  above  at  the  commencement  of  the  transverse  colon  just 
below  the  gall-bladder. 

The  descending  colon  and  sigmoid  flexure  are  usually  seen  lying  close  to  the 
abdominal  wall  somewhere  between  the  left  iliac  crest  and  approximately  the  middle 
of  Poupart's  ligament.  The  amount  visible  is  variable, — sometimes  a  considerable 
length  is  seen,  at  others  only  a  single  knuckle.  Their  presence  and  location  are 
more  uncertain  than  are  those  of  the  caecum  and  ascending  colon  on  the  right  side. 
The  S7nall  intestines  fill  the  rest  of  the  visible  space.  They  enter  the  pelvis,  usually 
are  found  in  hernial  sacs,  and  cover  both  the  ascending  and  descending  colon  in  the 
flanks.  The  coils  in  the  upper  and  left  portions  of  the  abdomen  are  more  likely  to 
be  jejunum,  those  in  the  lower  and  right  portions  are  more  likely  to  be  ileum. 
Either  may  be  found  in  the  pelvis. 

THE  STOMACH. 

When  the  stomach  is  moderately  distended  it  is  a  pear-shaped  organ  lying 
almost  entirely  to  the  left  of  the  median  line  and  occupying  the  epigastric  and  left 
hypochondriac  regions.  It  has  an  average  capacity  of  i  to  2  litres  (about  2^  pints). 
Its  direction  is  an  oblique  one,  being  downward,  forward,  and  to  the  right.     The 


Cardiac  end  ol 
stomach 


Spleen 

— Suprarenal  body 
— Kidney 

— Pancreas 


Transverse  meso- 
colon 


Pyloric  end  of  stomach 
Fig.  415. — The  bed  of  the  stomach.     The  stomach  has  been  removed  showing  the  surrounding  structures. 

upper  two-thirds  are  more  longitudinal,  the  lower  third  more  transverse,  the  two  parts 
making  an  angle  of  60  to  70  degrees.  The  part  just  adjoining  the  pylorus  is  slightly 
enlarged  when  the  stomach  is  distended,  and  is  called  the  antrum.  The  stomach 
is  spoken  of  as  having  anterior  and  posterior  walls,  but  they  could  just  as  truthfully 
be  called  superior  and  inferior,  especially  when  the  organ  is  distended.  When  it  is 
relaxed  it  tends  to  hang  in  a  more  vertical  position,  but  when  it  is  distended  it  rotates 
on  a  tranverse  axis,  the  greater  curvature  coming  forward,  and  the  organ  assumes 
a  more  horizontal  plane.  When  the  stomach  is  empty  it  may  not  be  relaxed  but 
contracted.  This  contraction  is  liable  to  be  very  marked  toward  the  middle  of  the 
organ,  producing"  the  hour-glass  stomach.  At  other  times  the  contraction  proceeds 
a  variable  distance  from  the  pylorus  toward  the  cardiac  extremity.  In  such  cases 
instead  of  being  pear-shaped  the  stomach  becomes  more  or  less  tubular  so  as  to 
resemble  the  remainder  of  the  intestinal  canal.  It  then  differs  but  little  in  appear- 
ance from  the  duodenum,  and  the  position  of  the  pylorus  is  not  readily  recognized. 
If,  as  may  normally  occur,  the  contraction  extends  well  over  toward  the  cardiac  end, 
then  liquids  do  not  lodge  in  the  stomach  but  pass  almost  immediately  through  it 
26 


402 


APPLIED    ANATOMY. 


into  the  small  intestine  beyond.  Wiien  this  condition  is  found  to  exist,  the  stomach 
is  to  be  recognized  by  its  position,  its  attachments,  and  the  thickness  of  its  walls. 
It  hangs  suspended  by  its  cardiac  extremity  from  the  oesophagus.  This  is  beneath 
the  seventh  left  costal  cartilage,  about  an  inch  from  the  edge  of  the  sternum  and 
lo  cm.  (4  in.)  from  the  surface;  this  brings  it  opposite  the  eleventh  dorsal  vertebra 
immediately  in  front  of  the  aorta.  The  pylorus  lies  just  under  the  edge  of  the  Hver, 
either  in  the  median  line  when  the  stomach  is  empty  or,  as  is  more  often  the  case, 
2.5  cm.  (i  in.)  or  more  to  the  right  of  the  median  line— a  Httle  higher  up  than  the 
gall-bladder  or  opposite  the  eighth  right  costal  cartilage  and  on  a  level  with  the  first 
lumbar  vertebra.  The  pylorus  is  usually  a  little  higher  in  women  than  in  men.  If  the 
liver  is  contracted  the  pylorus  and  adjacent  portion  of  the  stomach  may  be  in  direct 
contact  with  the  anterior  abdominal  wall.  The  lesser  curvature  is  7.5  to  12.5  cm. 
(3  to  5  in.)  long  and  passes  downward,  forward,  and  to  the  right. 

Relations. — The  stomach  rests  on  the  transverse  mesocolon,  which  covers  the 
pancreas,  solar  plexus,  aorta,  thoracic  duct,  vena  cava,  and  crura  of  the  diaphragm  pos- 


Diaphragmatic  branches 


Cceliac  axis 
Cystic  artery 

Hepatic 

Gastroduodenal 

Pyloric  branch 

Right  gastro-epiploic 


Gastric  (or  coronary) 


Splenic 

Superior  gastric 
lymph- nodes 

Left  gastro-epiploic 


Inferior  gastric 
lymph-nodes 


Fio.  416. — Blood  supply  and  lymphatics  of  the  stomach,  and  Hartmann-. Mikulicz  line. 

teriorly  ;  farther  to  the  left  are  the  left  suprarenal  body,  kidney,  and  spleen  (Fig.  415). 

In  front  are  the  diaphragm,  abdominal  parietes,  and  liver.  Above  are  the  lesser 
or  gastrohepatic  omentum,  liver,  and  diaphragm.  Below  is  the  gastrocolic  omen- 
tum, transverse  colon,  and  gastrosplenic  omentum. 

Percussion. — In  physical  diagnosis  the  size  of  the  stomach  is  outlined  by 
percussion,  it  being  filled  with  air  or  gas  to  distend  it.  In  the  median  line  its 
resonance  above  will  be  limited  by  the  edge  of  the  liver;  below,  while  usually  5  to 
7.5  cm.  (2  to  3  in.)  above  the  umbilicus,  it  is  not  considered  to  be  dilated,  especially 
in  old  people,  unless  it  reaches  below  the  uml)ilicus.  It  leaves  the  left  costal  margin 
opposite  the  ninth  or  tenth  costal  cartilage.  In  the  left  mammary  line  stomach 
resonance  may  reach  up  to  the  fifth  or  sixth  rib,  while  farther  to  the  left  it  reaches 
the  spleen  about  in  the  midaxillary  line. 

Traube' s  semilunar  space  is  limited  above  by  the  edge  of  the  left  lung,  indicated 
by  the  sixth  interspace  ;  externally  by  the  spleen,  indicated  by  the  midaxillary  line; 
and  internally  by  the  costal  margin.  Normally  this  area  is  resonant  from  the  presence 
of  the  stomach  beneath,  but  pleural  effusion  causes  it  to  be  dull  on  percussion. 


THE   STOMACH.  403 

Blood  Supply. — The  cceliac  axis  gives  off  the  gastric,  hepatic,  and  splenic 
arteries,  all  of  which  give  branches  to  the  stomach.  The  gastric  (or  coronary) 
gives  branches  to  the  oesophagus  and  cardiac  end  and  then  runs  along  the  lesser 
curvature  to  unite  with  the  pyloric  branch  of  the  hepatic.  It  lies  in  the  gastro- 
hepatic  omentum  and  sends  branches  anteriorly  and  posteriorly  o\er  the  surface  of 
the  stomach  (Fig.  416). 

The  hepatic  artery  as  it  nears  the  pylorus  gives  off  a  pyloric  branch  which  passes 
to  the  left  along  the  lesser  curvature,  and  a  gastroduodenal  branch,  which  divides 
into  the  superior  pancreaticoduodenal  to  supply  the  duodenum  and  head  of  the 
pancreas,  and  the  right  gastro-epiploic  artery  which  passes  to  the  left  along  the 
greater  curvature  of  the  stomach. 

The  splenic  artery  near  the  spleen  gives  off  the  left  gastro-epiploic  artery  which 
proceeds  along  the  greater  curvature  to  unite  with  the  right  gastro-epiploic,  a  branch 
of  the  gastroduodenal  artery. 

The  more  the  stomach  is  distended  the  closer  do  the  arteries  of  its  greater 
and  lesser  curvatures  lie  to  its  walls.  The  fundus  is  supplied  by  the  vasa  brevia, 
small  branches  which  leave  the  splenic  artery  in  the  gastrosplenic  omentum. 

The  veins  follow  the  course  of  the  arteries.  The  right  gastro-epiploic  empties 
into  the  superior  mesenteric  and  the  left  into  the  splenic;  they  then  enter  the  portal 
vein.  The  pyloric  and  coronary  veins  empty  into  the  portal  vein  direct.  The  latter 
receives  branches  from  the  oesophagus  which  become  varicose  in  cirrhosis  of  the 
liver. 

Lymphatics. — The  lymphatic  nodes  of  the  stomach  are  found  principally 
around  the  regions  of  the  pylorus — inferior  gastric  nodes,  and  the  lesser  curvature 
and  cardiac  extremity — superior  gastric  nodes.  The  inferior  nodes  drain  the  greater 
curvature  toward  the  pylorus  while  the  superior  nodes  drain  the  lesser  curvature  and 
cardiac  end.  The  fundus  is  drained  by  radicles  which  empty  into  the  nodes  which 
accompany  the  splenic  artery.  While  some  nodes  may  be  found  along  the  greater 
curvature  toward  the  pyloric  end,  Cuneo  and  Poirier  state  that  it  is  rare  to  find 
nodes  in  the  middle  portion  of  the  greater  curvature  and  quite  exceptional  to  meet 
with  them  in  the  region  of  the  fundus. 

AFFECTIONS   OF    THE  STOMACH. 

In  disease  the  stomach  may  be  contracted  or  dilated,  and  is  often  the  seat 
of  ulcer  and  carcinoma. 

Contracted  stomach  occurs  either  as  a  normal  or  pathological  condition;  it  has 
already  been  alluded  to  on  page  401.  The  contraction  of  the  middle,  producing  the 
hour-glass  shape,  results  from  cicatrices  and  adhesions  due  to  gastric  ulcer.  In 
cases  of  oesophageal  stricture  the  contraction  may  be  marked.  It  then  embraces 
mainly  the  right  third  of  the  organ  and  the  affected  portion  resembles  the  adjoining 
duodenum.  Abstention  from  food  in  the  course  of  an  illness  may  also  cause  a 
contracted  condition  which  one  should  be  prepared  to  encounter  in  case  of  opera- 
tion. A  normal  contracted  condition  of  the  right  end  of  the  stomach,  often  of  a 
more  or  less  hour-glass  shape,  is  frequently  encountered  in  autopsies  when  death 
has  been  caused  by  disease  of  other  organs  (Fig.  417). 

Dilation  results  from  functional  diseases  as  well  as  obstructive  affections,  such 
as  ulcer  or  carcinoma,  involving  the  pylorus.  Distention  causes  the  pylorus  to  pass 
from  the  midline  2. 5  to  7. 5  cm.  ( i  to  3  in. )  to  the  right.  The  organ  becomes  more 
horizontal  and  descends  so  that  its  lower  border  sinks  below  the  umbilicus — its  extreme 
normal  level.  Sometimes  the  greater  curvature  alone  is  lowered,  while  in  others  the 
gastrohepatic  omentum  is  stretched  and  the  pylorus  as  well  as  the  greater  curvature 
descends.  This  is  called  gastroptosis.  The  amount  of  distention  is  recognized  by 
percussion,  as  pointed  out  on  page  402,  or  by  administering  bismuth  and  examining 
by  the  Rontgen  rays. 

Ulcer  occurs  most  frequently  along  the  lesser  curvature;  then  the  posterior 
wall,  the  region  of  the  pylorus,  the  anterior  wall,  cardiac  end,  fundus,  and  greater 
curvature,  in  the  order  of  frequency.  The  ulceration  may  open  an  artery,  producing 
hemorrhage,  or  there  may  be  adhesions    to   neighboring  organs,  resulting  in  the 


404 


APPLIED    ANATOMY. 


formation  of  abscess,  or  direct  communication  with  the  greater  or  lesser  peritoneal 
cavity  may  be  produced.  Heahng  of  ulcers  near  the  pylorus  may  cause  stenosis 
resulting  in  distention.  Hemorrhage  may  occur  from  the  vessels  of  the  stomach 
walls  or  the  vessels  along  the  lesser  curvature,  the  splenic  or  hepatic  arteries  or  even 
the  portal  vein.  One  reason  why  the  arteries  along  the  curvatures  are  not  still  more 
frequently  affected  is  because  they  often  lie  a  short  distance  away  from  and  not 
in  immediate  contact  with  the  stomach  walls.  Adhesions  to  surrounding  organs  are 
least  liable  to  form  when  the  perforation  is  on  the  anterior  wall.  Then  the  larger 
peritoneal  cavity  is  infected  and  a  general  peritonitis  quickly  ensues.  A  perforation 
on  the  posterior  wall  involves  the  lesser  cavity  of  the  peritoneum,  and  the  infec- 
tion must  travel  first  through  the  foramen  of  Winslow  before  a  general  peritonitis 
develops.  Abscesses  may  form  between  the  under  surface  of  the  liver  and  the 
stomach,  and  they  have  been  known  to  penetrate  the  pleura,  pericardium,  and 
transverse  colon. 

Carcinoma. — This  is  located  in  about  60  per  cent,  near  the  pylorus,  in  15  per 
cent,  in  the  lesser  curvature,  in  10  per  cent,  at  the  cardiac  end,  and  in  the  remaining 


Fundus  of  stomach 


Contracted  right  end 
'  of  stomach 


Pylorus 


Duodenum 


Fig.  417. 


-Showing  the  right  end  of  the  stomach  normally  contracted  to  near  the  size  of  the  duodenum. 

an  actual  specimen. 


From 


15  per  cent,  in  other  portions  of  the  organ.  Cun^o  has  shown  that  extension 
occurs  in  the  lymphatic  nodes  along  the  lesser  curvature,  in  those  of  the  greater 
curvature  along  the  right  third  of  the  stomach  adjacent  to  the  pylorus,  and  in  the 
nodes  around  the  pylorus  and  head  of  the  pancreas.  It  has  been  noticed  that  there 
is  no  tendency  to  extension  to  the  region  of  the  duodenum.  It  will  thus  be  seen 
that  a  line  drawn  from  the  junction  of  the  right  and  middle  thirds  of  the  greater 
curvature  to  the  cardiac  extremity  would  have  nearly  all  the  nodes  to  the  right.  It 
is  this  portion  which  is  removed  in  pylorectomy  and  partial  gastrectomy;  owing  to 
the  extension  of  the  disease  up  the  lymphatics  of  the  oesophagus,  enlarged  nodes 
may  sometimes  be  present  in  the  left  supraclavicular  fossa  or  even  in  the  left 
axilla. 

The  tumor  is  usually  felt  in  or  near  the  median  line,  a  variable  distance  above 
the  umbilicus  ;  it  may  drag  the  pylorus  lower  down  than  normal.  If  the  stomach  is 
distended  the  tumor  may  be  carried  5  to  7.5  cm.  (2  to  3  in. )  to  the  right  of  the 
median  line.  If,  as  is  not  uncommon,  the  disease  infiltrates  the  walls  of  the  stomach, 
the  tumor  can  be  felt  passing  to  the  left  side,  disappearing  under  the  costal  margin. 


THE   STOiMACH.  405 

Adhesions  and  ulceration  are  common.  They  are  so  marked  that  peritonitis 
from  acute  perforation  is  moderately  rare.  The  adjacent  organs  are  matted  together 
and  purulent  collections  are  liable  to  occur.  The  ulceration  may  open  into  adjacent 
organs,  as  the  colon.  The  colon  may  be  adherent  to  the  stomach  and  the  large 
omentum  contracted  into  a  roll.  The  adhesions  and  pressure  from  the  growth  often 
interfere  with  the  biliary  ducts,  and  jaundice  ensues  ;  interference  with  the  portal 
vein  and  vena  cava  causes  ascites,  and  thrombosis  of  the  veins  sometimes  occurs. 
In  this  disease,  as  in  gastric  ulcer,  adhesions  are  least  liable  to  form  on  the  anterior 
wall,  and  here  perforation  requiring  operation  is  most  likely. 

OPERATIONS   ON  THE   STOMACH. 

The  following  operations  are  performed  on  the  stomach  :  gastrotomy,  or  the 
opening  of  the  stomach  to  remove  foreign  bodies  or  to  treat  ulcers  ;  gastrostomy,  or 
the  making  of  a  gastric  fistula  to  introduce  food  ,  pyloroplasty ,  or  the  widening  of  a 
constricted  pylorus ;  pyloredomy,  for  the  removal  of  cancerous  or  strictured  pylorus ; 
gastrectomy ,  or  the  removal  of  a  part  or  the  whole  of  the  stomach;  gastroplicaiio7i,  or 
the  folding  of  the  walls  to  reduce  its  size;  a.nd  gastro-e7iterostoj>iy,  or  the  establishing 
of  a  fistula  between  the  stomach  and  the  small  intestine. 

Technic. — The  incision  for  gastrostomy  is  4  cm.  (i  ^  in. )  long,  over  the  outer 
third  of  the  left  rectus  muscle,  beginning  2  cm.  (  ^  in. )  below  the  edge  of  the  ribs. 
The  fibres  of  the  rectus  are  to  be  parted  by  blunt  dissection  from  above  downward, 
as  this  is  less  apt  to  tear  the  lateral  branches  of  the  superior  epigastric  artery  than  if 
made  in  the  opposite  direction.  The  incisions  for  pyloroplasty  and  partial  or  complete 
gastrectomy  are  made  in  or  near  the  median  line  and  reach  from  the  tip  of  the  ensi- 
form  cartilage  to  the  umbilicus.  That  for  pyloroplasty  is  placed  usually, to  the  right 
of  the  median  line,  all  others  to  the  left.  In  incising  to  the  right  of  the  median  line 
the  incision  should  not  be  carried  down  to  the  umbilicus  or  the  round  ligamen*-  will 
be  cut.  The  incisions  are  placed  to  one  side  of  the  median  line  in  order  to  open  the 
sheath  of  the  rectus  and  pass  through  the  muscular  fibres,  thus  allowing  of  a  more 
secure  closure  of  the  wound  and  diminishing  the  liability  to  hernia.  In  incising  the 
posterior  layer  of  the  sheath  of  the  rectus  and  peritoneum  one  should  avoid  wounding 
the  edge  of  the  liver,  which  crosses  the  median  line  midway  between  the  xiphosternal 
articulation  and  umbilicus,  being  higher  or  lower  according  to  its  size.  The  stomach 
is  recognized  as  lying  immediately  below  and  in  contact  with  the  under  surface  of  the 
left  lobe  of  the  liver.  If  in  doubt,  follow  the  under  surface  of  the  liver  to  the  trans- 
verse fissure,  thence  over  the  lesser  or  gastrohepatic  omentum  to  the  lesser  curvature 
of  the  stomach.  The  omentum  may  present  in  the  wound  instead  of  the  stomach. 
It  is  to  be  pushed  downward  and  the  stomach  sought  for  under  the  liver.  The 
transverse  colon  should  not  be  mistaken  for  the  stomach.  It  lies  under  the  omentum 
and  can  be  identified  by  its  longitudinal  bands.  In  operating  on  the  pylorus  it  may 
be  found  lying  in  the  median  line  or  5  cm.  (2  in.)  or  even  7.5  cm.  (3  in.)  to  the 
right.  The  normal  pylorus  will  readily  admit  the  index  finger.  The  incision  ad\ised 
by  Finney  for  pyloroplasty  is  15  to  20  cm.  (6  to  8  in.)  long  through  the  right  rectus 
muscle. 

Partial  gastredoiny  is  the  operation  usually  done  for  carcinoma.  Pylorectomy 
is  too  incomplete  and  total  gastrectomy  is  too  dangerous,  in  performing  a  partial 
gastrectomy,  as  done  by  the  Mayo  brothers,  an  incision  just  to  the  left  of,  or  in,  the 
median  line  is  made  from  the  ensiform  process  to  the  umbilicus.  The  gastrohepatic 
omentum  is  then  ligated  from  the  pyloric  end  toward  the  cardiac  end,  well  beyond 
the  limits  of  the  tumor.  The  ligatures  are  to  be  placed  close  to  the  liver  and  suffi- 
ciently far  away  from  the  lesser  curvature  to  allow  of  the  remo\'al  of  the  lymphatic 
nodes  lying  along  it.  The  gastric  artery  is  ligated  below  the  cardiac  opening,  where 
it  reaches  the  lesser  curvature  (see  Fig.  416,  page  402),  The  pyloric  branch  of 
the  hepatic  is  ligated  as  it  reaches  the  stomach.  Ligate  the  gastroduodenal  artery 
behind  the  pylorus  and  the  gastro-epiploica  sinistra  on  the  greater  curvature;  the 
gastrocolic  omentum  is  then  to  be  ligated  between  the  two.  Care  is  to  be  taken 
not  to  ligate  the  colica  media  in  the  transverse  mesocolon  beneath  or  gangrene  of 
the  colon  will  result.     The  duodenum  is  then  clamped  and  cut,  and  also  the  stomach. 


4o6  APPLIED    ANATOMY. 

in  what  has  been  called  the  Hartmann-Mikulicz  Hne  (Fig.  416),  which  will  remove 
most  of  the  lesser  curvature  and  at  least  a  third  of  the  greater  curvature.  The  two 
cut  ends  are  then  closed  with  sutures  and  the  lowest  portion  of  the  remainder  of 
the  stomach  connected  with  the  ileum  either  anteriorly  or  posteriorly. 

In  performing  a  gastro-eiiterostomy  the  upper  portion  of  the  jejunum  is  brought 
up  and  anastomosed  with  the  anterior  or  posterior  wall  of  the  stomach.  If  the 
omentum  is  not  seen  at  once  on  opening  the  peritoneum  it  will,  perhaps,  be  found 
lying  rolled  up  along  the  lower  border  of  the  stomach.  It  is  to  be  brought  out 
of  the  wound  and  turned  upward.  On  its  lower  surface  is  seen  the  colon  running 
transversely  from  right  to  left.  Follow  the  transverse  mesocolon  down  to  the  spine 
and  the  commencement  of  the  jejunum  will  immediately  be  felt  and  can  be  seen 
coming  through  the  mesocolon,  with  the  ligament  of  Treitz  running  from  its  upper 
border  to  the  parietal  peritoneum.  Follow  the  jejunum  down  for  40  cm.  (16  in.) 
and  bring  it  up  in  front  of  the  great  omentum  and  colon  and  anastomose  with  the 
lower  border  of  the  stomach  anteriorly,  preferably  near  the  pyloric  end.      If  it  is 

Great  omentum 


Transverse  colon 
-Transverse  mesocolon 
Posterior  wall  of  stomach 

Duodenojejunal  flexure 


Fig.  418. — Posterior  gastro-enterostomy.  The  omentum  and  colon  have  been  turned  up  and  the  two  open- 
ings shown  in  the  stomach  and  commencement  of  jejunum  are  to  be  sewn  together  along  their  edges,  thus  estab- 
lishing a  communication  between  the  stomach  and  small  intestine. 

desired  to  do  a  posterior  gastro-enterostomy  the  transverse  mesocolon  is  divided 
and  the  stomach  pushed  forward  through  the  opening  (Fig.  418).  The  commence- 
ment of  the  jejunum  as  it  emerges  from  the  transverse  mesocolon  is  then  brought  up 
and  anastomosed  with  the  posterior  wall  of  the  stomach. 

THE  SMALL   INTESTINE. 

The  small  intestine  begins  at  the  pylorus  and  ends  at  the  ileocaecal  valve. 
It  has  an  average  length  of  6.75  metres  (22  ft.  6  in.)  in  the  adult,  independent  of  the 
age,  weight,  and  height  of  the  individual  (Treves).  Jonnesco  gives  its  length  as 
7.5  metres  (24  ft.  7  in.-)  and  Sappey  as  8  metres  (26  ft.  3  in.).  The  duodenum  is 
about  25  to  30  cm.  (10  to  12  in.)  long,  and  two-fifths  of  the  remainder,  or  about  8^ 
ft.,  is  jejunum,  and  three-fifths,  or  about  12}^  ft.,  is  ileum. 

THE    DUODENUM. 

The  duodenum  is  the  thickest,  widest,  and  most  fixed  portion  of  the  small 
intestine.  Its  diameter  is  from  3.75  cm.  to  5  cm.  (i)^  to  2  in. )  and  its  muscular 
and  mucous  coats  are  thicker  than  those  of  the  jejunum  or  ileum.  It  also  possesses 
in  its  upper  half  the  glands  of  Briuiner  (gla?idul(e  diiodenales^  in  the  submucous 
coat  It  is  thus  seen  that  in  its  structure  it  resembles  more  the  stomach  than  the 
intestine  and,  like  the  stomach,  is  especially  prone  to  ulcer.  While  carcinoma  fre- 
quently originates  at  the  pylorus  and  extends  to  and  involves  other  parts  of  the 


THE   SMALL   INTESTINE. 


407 


stomach,  it  does  not  tend  to  involve  the  duodenum.  This  is  probably  due  to  the 
lymph  stream  from  the  pylorus  running-  toward  the  stomach  and  away  from  the 
duodenum.  The  duotlenum  is  also  of  interest  in  consequence  of  its  intimate  relation 
to  the  biliary  passages  and  gall-bladder  as  well  as  to  the  pancreas  and  its  ducts. 
Inflammations,  such  as  accompany  gall-stones,  frequently  give  rise  to  adhesions,  to 
relieve  which  operations  are  performed.  The  second  portion  of  the  duodenum  is 
sometimes  opened  in  order  to  extract  a  biliary  calculus  impacted  in  the  ampulla  of 
Vater  at  the  mouth  of  the  common  bile-duct.  The  upper  portion  of  the  duodenum 
in  Finney's  operation  for  pyloroplasty  is  slit  down  from  the  strictured  pylorus  and 
sewed  to  a  corresponding  slit  in  the  stomach,  thus  making  a  large  communication 
between  the  duodenum  and  the  stomach  and  eliminating  the  stricture. 

In  shape  the  duodenum  resembles  a  horseshoe.  It  begins  on  the  right  side 
of  the  body  of  the  first  lumbar  vertebra  and  ends  on  the  left  side  of  the  body  of  the 
second  lumbar  vertebra.      At  its  commencement  it  is  suspended  from  the  liver  by 


Common  bile  duct 

First  portion  of 
duodenum 

Second  portion 
of  duodenum 


Pancreas 


Hepatic  flexure 
of  colon 


Pylorus 

Splenic  flexure 
of  colon 


Transverse 
mesocolon 
Duodenojejunal 
flexure 


Fourth  portion  of 
duodenum 


Third  portion  of  duodenum 
Mesentery 
Fig.  419. — The  duodenum,  showing  its  course  and  relation  to  the  surrounding  organs. 

the  duodenohepatic  ligament,  which  is  the  free  edge  of  the  gastrohepatic  omentum 
in  which  run  the  hepatic  artery,  portal  vein,  and  common  bile-duct. 

The  duodenum  is  composed  of  four  portions.  The  first  portion  (superior) 
begins  at  the  pylorus  and  ends  at  the  neck  of  the  gall-bladder.  It  is  about  5  cm.  (2 
in. )  long,  and  runs  backward  along  the  body  of  the  first  lumbar  vertebra.  The 
second  portion  (descending)  is  about  10  cm.  (4  in. )  long,  and  runs  down  the  right 
side  of  the  bodies  of  the  lumbar  vertebrae  to  the  lower  border  of  the  third.  The 
third  portion  (variously  called  ascending,  transverse,  or  inferior)  runs  diagonally 
upward  across  the  body  of  the  third  lumbar  vertebra  to  its  left  side  and  then  the 
fourth  portion  ascends  to  the  left  side  of  the  second,  where  it  takes  a  sharp  turn  and 
is  continued  as  the  jejunum  (Fig.  419). 

Relations. — First  portion:  Above  and  in  front  are  the  quadrate  lobe  of  the 
liver  and  the  gall-bladder;  below  is  the  pancreas;  and  behind,  from  left  to  right,  lie 
the  gastroduodenal  artery,  the  portal  vein,  the  common  bile-duct,  and  the  vena  cava. 

Second  portion  :  In  front  is  the  liver,  the  neck  of  the  gall-bladder,  and  the 
transverse  colon.  Behind  are  the  renal  vessels,  ureter,  right  kidney,  and  psoas 
muscle.  To  its  inner  side  lie  the  pancreas  and  vena  cava.  The  common  bile-duct 
runs  on  the  inner  side  between  the  duodenum  and  the  pancreas;  at  the  middle  of  this 
portion  of  the  duodenum  the  bile-duct  joins  with  the  pancreatic  duct  to  empty  into 
the  duodenum  through  the  ampulla  of  Vater,  about  10  cm.  (4  in. )  from  the  pylorus. 


4o8 


APPLIED    ANATOMY. 


Third  portion:  In  front  are  the  superior  mesenteric  artery  and  root  of  the 
mesentery;  behind  lie  the  vena  cava,  aorta,  and  left  psoas  muscle.  Above,  it  lies 
in  contact  with  the  pancreas.  The  termination  of  the  duodenum  is  usually  on  the 
left  of  the  aorta,  but  Dwight  (Joiirtial  of  A?iatomy  and  Physiology,  vol.  xxxi,  p. 
576)  in  fifty-four  cases  found  it  twenty-six  times  on  the  right  of  the  aorta  until  just 
before  its  terminal  flexure.  It  was  wholly  on  the  right  side  six  times,  in  front  of  the 
aorta  eleven  times,  and  had  crossed  the  aorta  eleven  times. 

Peritoneal  Covering. — First  part:  The  pyloric  half  is  almost  completely 
covered  by  peritoneum,  but  the  distal  half  only  on  its  anterior  surface.  Second  part: 
No  peritoneum  on  its  inner  and  posterior  surfaces,  and  only  on  its  outer  and  anterior 
where  not  covered  by  the  transverse  colon.  Third  and  fourth  parts:  The  anterior 
and  left  sides  are  covered  by  peritoneum  except  where  crossed  by  the  root  of  the 
mesentery  and  superior  mesentric  vessels. 

JEJUNUM    AND   ILEUM. 

The  jejunum  is  about  8^  ft.  long  and  the  ileum  about  12^2,  ft.  They  are 
bound  to  the  spinal  column  by  the  mesentery,  which  extends  from  the  left  side  of  the 
body  of  the  second  lumbar  vertebra  to  the  right  sacro-iliac  joint. 

Duodenojejunal  Flexure  and  Fossae. — The  point  of  ending  of  the  duo- 
denum and  beginning  of  the  jejunum  is  marked  by  a  sharp  bend  called  the  duodeno- 


Duodenojejunal  flexure  / 


Middle  colic  artery 


Suspensory  ligament  or 
muscle  of  Treitz 


Superior  duodenal  fossa 
Inferior  mesenteric  vein 

Inferior  duodenal  fossa 
Fourth  portion  of  duodenum 
Inferior  mesenteric  artery 


Fio.  420. — The  duodenojejunal  flexure  and  duodenal  fossa;  the  jejunum  drawn  to  the  right. 

jejunal  flexure.  The  beginning  of  the  jejunum  passes  downward,  forward,  and 
usually  toward  the  left.  If  the  transverse  colon  is  thrown  upward  and  the  jejunum 
is  pulled  sharply  to  the  right,  a  folded  edge  of  peritoneum  containing  some  muscular 
fibres  is  seen  passing  from  the  flexure  to  the  parietal  peritoneum.  This  is  called 
the  suspensory  ligament  or  muscle  of  Treitz.  The  fossa  which  is  behind  it  is  the 
superior  duodenojejunal  fossa  of  Treitz  while  that  below  is  the  inferior  duodenal 
fossa.  Below  the  fossa  runs  the  inferior  mesenteric  artery  and  near  the  left  edge  of 
the  ligament  runs  the  inferior  mesenteric  vein.  Into  the  fossae,  if  abnormally  large, 
the  intestines  may  enter  and  produce  a  retroperitoneal  hernia.  If  the  constricting 
band,  which  is  the  ligament  of  Treitz,  is  cut,  there  is  danger  of  dividing  the  inferior 
mesenteric  vein  (see  Fig.  420). 

The  small  intestine  decreases  in  size  and  thickness  from  its  upper  to  its  lower 
end.  The  diameter  of  the  jejunum  is  about  4  cm.  ( i  ^  in.  )  while  that  of  the  ileum 
is  about  3  cm.  (i^  in.). 

The  walls  of  the  jejunum  are  thicker,  redder,  and  more  vascular  than  those  of  the 
ileum  and  the  valvulae  conniventes  are  better  developed.  The  ileum  is  thinner,  nar- 
rower, paler  and,  particularly  when  diseased,  the  large  Peyer's  patches  can  be  seen. 

The  intestinal  coils,  while  not  constant  in  position,  are  most  apt  to  be  as 
follows :  The  commencement  of   the   jejunum  is  in  the  upper  left  portion  of  the 


THE   SMALL   LNTESTINE.  409 

abdomen.  The  ileum  is  more  in  the  right  lower  quadrant  of  the  abdomen.  Accord- 
ing to  Trex'es,  the  intestine  from  six  to  eleven  feet  from  its  commencement  has  the 
longest  mesentery  and  is  apt  to  be  found  in  the  pelvis.  The  lower  end  of  the  ileum 
is  also  usually  found  in  the  pelvis,  and  rises  over  its  brim  to  join  the  caecum. 

There  is  no  certainty,  however,  of  finding  a  definite  piece  of  the  small  intestine 
under  any  special  point  on  the  surface,  because  the  varying  distention  and  move- 
ments cause  frequent  changes  of  position. 

Meckel's  Diverticulum. — In  the  embryo  the  vitello-intestinal  duct  passes 
from  the  umbilicus  to  the  lower  end  of  the  small  in- 
testine. Normally  this  disappears,  but  sometimes  a 
portion  of  it  remains  and  there  is  found,  one  to  three 
feet  above  the  ileocaecal  valve,  a  finger-like  projec- 
tion from  the  side  of  the  ileum,  5  to  7.5  cm.  (2  to 
3  in.)  long.  This  is  called  MeckeV s  divertiaihim, 
and  may  become  the  site  of  disease  the  same  as  the 
rest  of  the  ileum.  From  its  extremity  a  fibrous  band 
may  run  to  the  umbilicus.  This  has  been  in  rare 
instances  the  source  of  strangulation,  causing  intesti- 
nal obstruction.  One  such  case  has  been  under  our 
care  (Fig.  421). 

Peyer's  patches  (noduli  lymphatic!  aggre- 
gati)  are  most  numerous  in  the  lower  portion  of  the 
ileum.  They  are  ulcerated  in  typhoid  cases  and  are 
frequently  the  site  of  perforations.  These  patches 
are  from  i  to  2.5  cm.  (^  to  i  in.)  wide  and  2.5  to 

7.5  cm.  ( I  to  3  in. )  long.  When  affected  in  typhoid  ^^•^•^"•"^luthS'JSch')"'"*  ^^'^°'" 
fever  they  can  readily  be  seen  through  the  intestinal 

walls.  By  holding  the  intestine  up  against  the  light  both  Peyer's  patches  and  the 
valvulae  conniventes  can  readily  be  seen. 

The  perforations  in  typhoid  fever  occur  usually  within  three  feet  of  the  ileo- 
caecal valve,  though  occasionally  they  may  occur,  as  we  have  seen,  in  the  appendix, 
or  higher  up  in  the  small  intestine,  or  even  in  the  large  intestine. 

OPERATIONS. 

The  small  intestines  are  frequently  resected  and  anastomosed  with  themselves 
or  other  portions  of  the  gastro-intestinal  canal.  Gastro-enterostomy  has  been  alluded 
to  on  page  406. 

On  opening  the  abdomen,  if  it  is  desired  to  find  the  upper  end  of  the  small 
intestine,  the  omentum  is  pulled  out,  drawing  with  it  on  its  under  surface  the 
transverse  colon.  The  hand  is  to  be  passed  backward  on  the  under  surface  of  the 
transverse  mesocolon  until  the  spine  is  reached;  on  its  left  side  will  be  felt  the  duo- 
denojejunal flexure.  On  drawing  the  jejunum  to  the  right,  the  ligament  of  Treitz 
will  be  seen.  A  loop  40  cm.  (16  in.)  down  may  be  taken  and  brought  up  in  front 
of  the  omentum  and  used  for  an  anterior  gastro-enterostomy,  or  the  intestine 
immediately  below  the  flexure  may  be  used  for  a  posterior  gastro-enterostomy  (see 
page  406).  If  one  desires  to  find  the  lower  end  of  the  small  intestine,  then  a  search 
is  made  for  the  colon  in  the  right  iliac  region.  It  is  recognized  by  its  longitudinal 
bands  and  is  followed  down  to  the  ileocaecal  junction.  If  the  case  is  one  of  typhoid 
fever,  a  rapid  examination  is  then  made  from  the  ileocaecal  valve  upward  for  perfora- 
tions. It  is  desirable  at  times  to  determine  which  is  the  proximal  and  which  the 
distal  end  of  an  intestinal  loop.  The  best  way  to  do  so  is  to  follow  the  loop  down 
to  the  mesenteric  attachment,  as  advised  by  Monks ;  if  the  mesentery  proceeds  up 
and  to  the  left  you  have  the  proximal  end;  if,  however,  it  is  passing  down  to  the 
right  you  have  the  distal  end. 

The  intestine  receives  its  nourishment  from  the  mesentery  and  will  die  when 
detached,  hence  it  is  necessary  to  avoid  injury  or  detachment  of  the  mesentery  or 
its  vessels ;  when  this  detachment  has  occurred  the  involved  portion  of  intestine  is 
resected  and  removed. 


4IO 


APPLIED    ANATOMY. 


THE   MESENTERY. 


Root  of  mesentery 


The  mesentery  extends  from  the  left  side  of  the  body  of  the  second  lumbar 
vertebra  to  the  right  sacro-iliac  joint.  It  is  from  15  to  20  cm.  (6  to  8  in.)  long  at 
its  root  and  spreads  out  like  a  fan,  to  be  attached  to  the  small  intestine.  It  is  com- 
paratively thick,  especially  toward  its  root,  and  contains  the  superior  mesenteric 
artery  and  veins,  nerves,  and  lymphatics.  The  mesenteric  lymphatic  nodes  are 
numerous,  from  130  to  150  (Quain)  in  number.  They  are  frequently  involved  in 
carcinoma  and  tuberculosis,  and  may  form  masses  which  may  be  mistaken  either  for 
independent  tumors  or  outgrowths  from  other  organs.  They  are  sometimes  inflamed, 
and  even  cause  abscess,  being  mistaken  for  appendix  disease.  They  become  calcare- 
ous and  by  the  Rontgen  rays  may  cast  shadows  which  have  been  mistaken  for  calculi 
of  the  urinary  organs. 

The  mesentery  has  its  vessels  sometimes  ruptured  by  violence  or  blocked  by 
emboli  or  thrombi.  This  is  likely  to  cause  gangrene  of  the  intestine  to  which  they 
are  distributed.      In  abdominal  operations  the  greatest  care  is  to  be  taken  not  to 

injure  these  vessels,  and  in 
hemorrhage  the  least  possi- 
ble amount  of  ligation  is  to 
be  done.  Obstructions  of  a 
mesenteric  branch  may  ne- 
cessitate the  resection  of  that 
part  of  the  small  intestine 
which  it  supplies. 

It  is  particularly  im- 
portant to  bear  in  mind  the 
direction  of  the  mesenteric 
attachment  on  account  of  its 
influence  in  directing  the 
course  of  the  blood  in  cases 
of  hemorrhage.  The  small 
intestines  are  attached  at  the 
root  of  the  mesentery  like  the 
leaves  of  a  book  to  its  back. 
Bleeding  originating  from  the 
right  and  upper  quadrants  of 
the  abdomen  will  pass  over 
the  intestines  and  tend  to 
gravitate  toward  the  right 
iliac  fossa.  Bleeding  originat- 
ing from  the  left  and  lower 
quadrants  tends  to  pass  under  the  intestines  toward  the  left  iliac  fossa.  In  searching 
the  abdomen  through  a  large  median  incision  for  the  source  of  a  concealed  hemor- 
rhage, the  intestines  are  first  to  be  pushed  down  and  to  the  left,  and  the  right  side  of 
the  abdominal  wall  lifted  with  retractors.  This  will  expose  to  view  the  upper  surface 
of  the  small  intestines,  the  ascending  and  transverse  colon,  the  right  kidney,  liver, 
stomach,  and  head  of  the  pancreas.  Should  additional  search  be  necessary  the  small 
intestines  are  to  be  raised  and  turned  upward  and  to  the  right  (Fig.  422),  being 
brought  out  of  the  wound  if  necessary.  This  will  expose  the  under  side  of  the  small 
intestines  and  mesentery,  the  sigmoid  flexure,  descending  colon,  left  kidney,  spleen, 
and  tail  of  the  pancreas,  with  the  left  end  of  the  stomach  and  left  lobe  of  the  liver 
above.  The  intestines  are  never  to  be  turned  downward  to  the  right  nor  upward 
to  the  left. 

The  mesentery  attains  its  greatest  length,  according  to  Treves,  from  6  to  1 1  feet 
below  the  duodenum,  where  it  measures  25  cm.  (10  in.)  In  hernia  the  mesentery 
is  lengthened  to  allow  of  the  descent  of  the  gut.  Rarely  openings  are  present  in 
the  mesentery  which  may  allow  the  entrance  and  strangulation  of  a  coil  of  the 
intestine. 


Intersigmoid  fossa 
(recessus  intersigmoideus) 


Fig.  422. — The  mesentery  is  seen  running  downward  toward  the 
right  sacro-iliac  joint;  the  index  finger  is  below  it  and  the  other  three 
fingers  above.  The  small  intestines  have  been  raised  on  the  hand  and 
turned  upward  thus  exposing  the  pelvis  and  entire  left  lower  half  of  the 
abdomen  for  examination. 


THE   LARGE   INTESTINE.  411 


THE  LARGE  INTESTINE. 

The  large  intestine  comprises  (i)  the  cacuni  and  appeyidix,  (2)  ascending 
colon,  (3)  transverse  coloft,  (4)  descending  colon,  (5)  sigmoid  Jlexiire,  composed  of 
the  iUac  colon  and  pelvic  colon,  and  (6)  the  rectum  and  anal  catial. 

The  length  of  the  large  intestine  exclusive  of  the  rectum  and  anal  canal  is  135 
cm.  (4  ft.  6  in.)  in  the  female,  and  140  cm.  (4  ft.  8  in.)  in  the  male.  If  the  anterior 
abdominal  wall  is  removed  the  caecum  and  part  of  the  ascending  colon  are  visible, 
but  in  the  upper  part  of  the  lumbar  region  the  colon  disappears,  being  overlaid  by 
the  small  intestine.  Having  turned  at  the  hepatic  flexure,  it  again  comes  into  view 
below  the  lower  edge  of  the  liver  and  passes  superficially  across  the  abdomen  to 
disappear  under  thq  left  costal  margin  to  form  the  splenic  flexure.  It  is  not  visible 
again  until  it  reaches  the  region  of  the  crest  of  the  ilium,  where  it  once  more 
becomes  superficial  and  follows  the  inguinal  (Poupart's)  ligament  down  to  near  its 
lower  end,  where  it  turns  backward  and  upward  to  form  the  sigmoid  loop  which 
descends  along  the  sacrum.  In  operating  it  is  necessary  to  be  able  to  distinguish 
large  from  small  intestine. 

Size. — The  large  intestine  at  its  commencement  at  the  caecum  may  have  a 
diameter  of  7.5  cm.  (3  in.),  but  it  decreases  in  size,  and,  especially  if  empty,  the 
descending  colon  and  sigmoid  flexure  may  only  be  2.5  cm.  (i  in.)  in  diameter.  A 
distended  part  of  the  small  intestine  will  be  larger  than  a  contracted  part  of  the 
colon.  Inasmuch  as  operations  are  frequently  done  for  obstructive  conditions  which 
greatly  enlarge  the  involved  parts,  it  is  unreliable  to  depend  on  size  as  distinguishing 
the  large  intestine.  There  are  three  longitudinal  bands  {tcBnice  colt)  on  the  colon, 
from  6  to  12  mm.  (^^^  to  ^  in. )  wide,  according  to  the  amount  of  distention.  One 
is  anterior,  another  postero-external,  and  the  third  postero-internal.  On  the  trans- 
verse colon  they  haA-e  the  same  relative  position  when  the  great  omentum  and  colon 
are  raised  and  turned  upward.  They  all  begin  at  the  appendix  and  traverse  the 
large  intestine  until  the  rectum  is  reached,  where  they  blend  together,  forming  a 
longitudinal  layer  which  is  weak  at  the  sides  and  strong  anteriorly  and  posteriorly. 

Sacculation  of  the  colon  is  produced  by  the  longitudinal  bands  being  one- 
sixth  shorter  than  the  rest  of  the  tube.  While  sacculation  tends  to  become  less 
marked  on  distension,  it  is  still  a  valuable  means  of  identification.  Dividing  the 
longitudinal  bands  will  cause  the  sacculation  to  disappear  and  the  gut  to  lengthen. 

Appendices  epiploicae  or  the  small  tags  of  peritoneum  containing  fat,  are 
found  along  the  large  intestine  as  far  as  the  rectum.  They  are  most  numerous  along 
the  inner  longitudinal  band  and  the  transverse  colon. 

C^CUM    AND    APPENDIX. 

The  caecum  is  the  blind  pouch  of  the  large  intestine  which  extends  beyond  the 
opening  of  the  ileum.  It  is  about  7.5  cm.  (3  in.)  broad  and  6.25  cm.  (2>^  in.) 
long.  Its  three  longitudinal  bands  converge  to  the  appendix  and  are  continued  over 
it.  It  lies  in  the  right  iliac  fossa  on  the  iliacus  and  psoas  muscles,  more  on  the 
latter,  and  reaches  nearly  or  quite  to  its  inner  edge.  It  is  in  contact  with  the 
abdominal  wall  above  the  outer  half  of  the  inguinal  (Poupart's)  ligament.  In  fetal 
life  the  caecum  is  cone-shaped  and  passes  gradually  and  regularly  into  the  appendix. 
It  increases  in  size  more  rapidly  on  its  outer  side,  so  that  the  appendix,  which  was 
before  opposite  the  long  axis  of  the  gut,  becomes  placed  to  the  inside  just  below  the 
ileocaecal  valve. 

Four  varieties  of  caecum  are  given  by  Treves:  (i)  the  conical  or  fetal  type,  (2) 
a  globular  or  quadrilateral  type,  in  which  the  development  of  both  sides  is  even,  (3) 
the  adult  type,  in  which  the  outer  side  is  much  larger  than  the  inner,  (4)  an  irregular 
type,  in  which  there  is  an  excess  of  development  of  the  outer  side  and  an  atrophy 
of  the  inner  side  resulting  in  placing  the  root  of  the  appendix  close  to  the  lower  and 
posterior  portion  of  the  ileocaecal  junction. 

Cunningham  makes  three  varieties:  (i)  a  fetal  conical  type,  (2)  an  infantile 
type,  in  which  the  outer  side  is  somewhat  larger  than  the  inner,  and  (3)  an  adult 


412 


APPLIED   ANATOMY. 


type,  93  or  94  per  cent. ,  in  which  the  outer  side  is  much  the  larger,  and  the  root  of 
the  appendix  is  on  the  inner  wall  just  below  the  ileocaecal  valve  (in  the  adult  about 
2  cm. — 3/^  in.  ). 

The  ileocaecal  valve  marks  the  emptying  of  the  ileum  into  the  large  intestine. 
On  the  surface  of  the  body  it  corresponds  to  a  point  2.5  cm,  (i  in.)  below  the 
middle  of  a  line  joining  the  anterior  superior  spine  and  the  umbilicus  and  the  same  dis- 
tance above  the  middle  of  a  transverse  line  drawn  from  the  anterior  superior  spine  to 
the  median  line.  This  point  is  about  on  the  linea  semilunaris  and  directly  above  the 
point  where  the  external  iliac  artery  passes  under  Poupart's  ligament.  Normally 
the  ileocaecal  valve  will  allow  of  the  passage  of  gas  from  the  colon  into  the  ileum,  as 
in  Senn's  hydrogen  test  for  perforation,  but  not  of  liquids  or  solids. 

Vermiform  Appendix  (processus  vermiformis).  —  The  appendix  varies 
much,  both  in  length  and  diameter.      In  health  its  average  length  may  be  given  as 

from  8.75  cm.  (3^  in.)  to  10  cm.  (4  in.) 
and  its  diameter  as  6  mm.  (}(  in.).  It  is 
pale  in  color  and  soft  in  consistence,  with 
its  blood-vessels  barely  visible.  In  disease 
it  becomes  hard  and  red  and  the  injected 
vessels  are  distinctly  seen.  It  becomes 
much  increased  in  diameter,  equalling  in 
size  a  finger  or  thumb,  and  lengthens  to 
15  cm.  (6  in.)  or  even  more.  It  possesses 
a  serous  peritoneal  coat,  a  longitudinal 
muscular,  a  circular  muscular,  a  submucous 
and  a  mucous  coat.  The  lumen  of  the 
appendix  has  been  found  to  be  partially 
occluded  in  at  least  one-fourth  of  all  adults. 
This  occlusion  occurring  toward  its  distal 
extremity  is  not  regarded  as  pathological, 
but  constrictions  occurring  elsewhere  in  the 
length  of  the  tube  are  probably  the  result 
of  previous  disease. 

The  opening  of  the  appendix  in  the 
caecum  is  about  2.5  cm.  (i  in.)  below  and 
a  little  behind  the  ileocaecal  opening.  The 
fold  of  mucous  membrane  guarding  it  has 
been  named  the  va/ve  of  Gcrlach  but  it  is 
not  generally  regarded  as  a  distinct  valve. 
The  root  of  the  appendix  is  only  about  2 
cm.  ( ^  in. )  below  the  lower  edge  of  the  ileum  and  is  often  even  closer  on  account 
of  the  lower  surface  of  the  ilium  being  in  contact  with  the  caecum  at  that  point.  It 
corresponds  to  a  point  on  the  surface  of  the  body  where  the  right  semilunar  line 
crosses  a  line  joining  the  two  anterior  superior  spines  (Fig.  423). 

The  meso-appendix  (mesenteriolum)  comes  off  the  lower  surface  of  the 
mesentery.  It  is  shorter  than  the  appendix,  hence  the  twisting  and  curling  of  the 
latter.  It  usually,  but  not  always,  extends  to  the  tip  and  contains  toward  its  left  or 
free  border  the  appendicular  artery. 

The  ileocolic  artery,  from  the  superior  mesenteric,  as  it  approaches  the  ileo- 
caecal junction  divides  into  five  branches:  (i)  the  colic,  distributed  to  the  colon;  (2) 
the  ileal,  to  the  upper  surface  of  the  ileum;  (3)  xhe  anterior  ileoccscal  branch,  to  the 
front  of  the  caecum,  passing  through  the  ileocolic  fold;  (4)  ih^  posterior  ileoccecal 
artery,  to  the  posterior  part  of  the  caecum;  (5)  the  appendicular  artery.  The  appen- 
dicular artery  descends  behind  the  ileum  to  enter  the  meso-appendix  and,  after  sending 
one  recurrent  branch  to  the  root  of  the  appendix  and  another  to  the  ileocaecal  fold, 
passes  along  the  left  or  free  edge  of  the  meso-appendix,  and,  if  this  is  short,  it  may 
be  continued  on  the  surface  of  the  appendix  to  its  extremity  (Fig.  424). 

In  removing  the  appendix  this  artery  requires  ligation  and  if  the  ligature  is  not 
placed  close  to  the  root  the  recurrent  branches  will  not  be  included  and  may  cause 
dangerous  bleeding. 


if 

\ 


\    S 


Fig.  423. — The  relations  of  the  appendix.  The 
ileocaecal  junction  is  seen  to  be  about  one  inch  below 
the  middle  of  a  line  joining  the  anterior  superior 
spine  and  umbilicus  or  where  this  line  crosses  the 
linea  semilunaris.  The  base  of  the  appendix  is  under 
the  point  of  crossing  of  the  linea  semilunaris  and  the 
middle  of  a  horizontal  line  running  from  the  anterior 
superior  spine  to  the  mid-line  of  the  body;  it  is  one 
inch  below  the  ileocaecal  junction. 


THE   LARGE    INTESTINE. 


413 


The  veins  of  the  appendix  and  the  caecum  end  in  the  ileocolic  vein,  which  joins 
the  superior  mesenteric  vein  and  helps  to  form  the  portal  vein.  Hence  infection  is 
carried  by  the  blood  stream  from  the  appendix  and  caecum  directly  to  the  liver. 

Position  of  the  Appendix. — The  position  and  direction  of  the  appendix  have 
been  variously  described  and  much  discussed.  This  has  arisen  from  the  fact  that  it 
is  so  curled,  curved,  and  twisted  on  itself  that  it  is  impossible  to  say  that  it  points  in 
any  definite  direction,  and  that,  being  so  mobile,  it  may  be  found  in  almost  any  posi- 
tion, swinging  around  with  its  point  of  attachment  to  the  caecum  as  the  axis.  We 
agree  with  Cunningham  when  he  says  that  it  runs  generally  in  one  of  three  direc- 
tions: (i)  over  the  brim  into  (or  towards)  the  pelvis;  (2)  upward  behind  the  caecum; 
(3)  upward  and  inward  toward  the  spleen.  As  he  says,  each  of  these  has  been  con- 
sidered the  normal  position  by   one  or   more   observers.      It   is   evident   that,  as 


RetrocoHc  fossa 


Colic  branch 


Ileocolic  artery- 
Anterior  ileocaecal 
branch 

Superior  ileocaecal  fold 
Ileal  branch 
Superior  ileocaecal  fossa 

Posterior  ileocajcal 
branch 

Inferior  ileocascal  fold 
Inferior  ileocaecal  fossa 
Appendicular  artery 

Recurrent  branch 
Meso-appendix 


RetrocoHc  fold^ 

RetrocoHc  fossa 
Fig.  424. — The  appendix  and  ileocaecal  region,  showing  the  folds,  fossae,  and  arteries. 


the  appendix  comes  off  close  to  the  ileum,  this  is  its  most  fixed  and  constant  point. 
In  certain  cases  the  caecum  retains  its  high  fetal  position  and  then  the  appendix  will 
be  higher  than  usual.  If  the  appendix  is  long  and  straight,  its  tip  may  reach  to  or 
beyond  the  median  line;  it  may  lie  in  contact  with  the  rectum,  ovary,  tube,  or  blad- 
der; it  may  lie  low  down  close  to  Poupart's  ligament  or  curved  upward  behind  the 
colon,  reaching  in  front  of  the  kidney  and  nearly  or  quite  to  the  liver.  When  retro- 
caecal  it  lies  on  the  quadratus  lumborum;  when  lower  it  may  lie  on  the  iliacus  or 
psoas  muscle.  If  it  goes  over  the  brim  of  the  pelvis  it  lies  on  the  external  iliac 
artery.  The  external  iliac  vein  is  below  and  to  the  inner  side  and  is  largely  pro- 
tected from  injury  in  operating  by  the  stronger  and  tougher  artery. 

Caecal  Folds  and  Fossae. — There  are  three  folds  and  three  fossae  formed  by 
the  peritoneum  in  the  neighborhood  of  the  caecum. 

I.  The  superior  ileoccecal  {ileocolic)  fold  runs  from  the  upper  surface  of  the 
mesentery  just  above  the  ileum  to  the  upper  anterior  surface  of  the  caecum.  In  it 
runs  the  ileocecal  {anterior)  artery.  Beneath  it,  with  its  opening  toward  the  left,  is 
the  superior  ileocecal  fossa  (Fig.  424). 


APPLIED    ANATOMY. 

2.  The  inferior  ileoccecal fold  passes  from  the  termination  of  the  ileum  to  the 
front  of  the  meso-appendix  ;  it  contains  a  small  recurrent  branch  of  the  appendicular 
artery.  Beneath  it  and  between  it  and  the  meso-appendix  is  the  inferior  ileoccicat 
fossa,  which  may  sometimes  contain  the  appendix. 

3.  The  rctrocolic  fold  is  not  constant  and  may  be  multiple.  It  passes  from  the 
lower  and  outer  surface  of  the  caecum  to  the  peritoneum  beneath.  It  binds  down  the 
end  of  the  caecum  and  not  infrequently  must  be  divided  before  the  caecum  and 
appendix  can  be  raised;  the  fossae  on  each  side  of  it  are  called  the  retrocolic fosses. 

Lymphatics  of  the  Caecum  and  Appendix. — The  lymphatics  of  the  caecum 
and  appendix  drain  into  a  group  located  in  the  mesentery  of  the  ileocaecal  angle, 
accompanying  the  ileocolic  artery.  According  to  Poirier  and  Cuneo  there  are  three 
sets :  an  anterior  caecal,  a  posterior  caecal,  and  an  appendicular. 

The  anterior  ccecal  lymphatics  drain  the  anterior  surface  of  the  caecum  and,  aftt;r 
traversing  one  or  two  small  nodes,  pass  in  the  ileocaecal  fold  up  to  the  main  ileo- 
caecal group. 

The  posterior  ceecal  lymphatics  drain  the  posterior  portion  of  the  caecum  and, 
after  traversing  three  to  six  small  nodes,  empty  likewise  into  the  ileocaecal  group. 

The  appendicular  lymphatics  form  four  or  five  trunks  which  accompany  the 
artery  between  the  layers  of  the  meso-appendix.  They  then  pass  across  the  posterior 
surface  of  the  ileum  to  empty  into  the  ileocaecal  group. 

Poirier  and  Cun6o  state  that  these  lymph-trunks  from  the  appendix  pass  through 
one  to  three  nodes  placed  in  the  retro-ileal  portion  of  the  meso-appendix,  but  Kelly 
and  Hurdon  state  that  in  the  majority  of  cases  these  trunks  empty  into  one  or  two 
nodes  some  distance  above  the  ileum  in  the  ileocaecal  angle,  forming  a  part  of  the 
ileocaecal  chain.  These  latter  authors  state  that  there  are  three  sets  of  lymph- 
capillaries  in  the  appendix  :  a  superficial  or  subperitoneal  set,  another  between  the 
submucous  and  muscular  layers,  and  a  deep  set  in  the  mucosa  around  the  glands  of 
Lieberkulm. 

The  three  great  lymph-streams,  anterior  caecal,  posterior  caecal,  and  appendicu- 
lar, are  quite  distinct  from  each  other  and  from  the  surrounding  lymphatics  of  the 
pelvis  and  colon;  when  these  latter  are  involved  it  is  not  by  a  lateral  extension 
from  these  three  streams  but  by  direct  infection  from  the  regions  which  they  them- 
selves drain.  From  the  ileocaecal  nodes  the  lymphatics  follow  the  arteries  to  the 
nodes  at  the  root  of  the  mesentery  and  empty  into  the  receptaculum  chyli.  They 
do  not  follow  the  veins  to  the  liver,  hence  infection  of  the  liver  is  not  caused  through 
the  lymph-channels  in  appendicitis. 

Appendicitis. — Diagnosis. — The  most  fixed  part  of  the  appendix  is  its  root. 
This  corresponds  to  a  point  on  the  linea  semilunaris  opposite  to  the  anterior  superior 
spine  of  the  ilium.  The  painful  tip  of  the  appendix  may  be  anywhere  in  a  circle 
around  this  point  10  cm.  (4  in.)  in  radius.  It  may  be  lying  posterior  and  simulate 
calculus  or  other  kidney  trouble;  it  may  be  up  toward  the  liver  or  gall-bladder;  it 
may  be  toward  the  left,  even  beyond  the  midline;  it  may  be  in  Douglas's  cul-de-sac 
and  be  confounded  with  disease  of  the  uterus,  tubes,  and  bladder.  It  overlies  the 
ureter  and  may  be  mistaken  for  calculus  therein.  An  enlarged  gall-bladder  can 
have  its  painful  apex  at  McBurney's  point.  Typhoid  ulcers  occur  close  to  and,  as 
we  have  observed,  may  involve  the  appendix.  All  these  relations  must  be  remem- 
bered. McBurney  placed  the  most  tender  point  4  to  5  cm.  ( i  )^  to  2  in. )  from  the 
anterior  superior  spine  in  a  direction  toward  the  umbilicus.  Personally  we  would 
place  it  near  the  root  of  the  appendix  at  least  2.5  cm.  (i  in.)  lower  down  and 
a  little  farther  in. 

Operation. — An  incision  for  appendicitis  often  used  is  a  longitudinal  one  over  the 
edge  of  the  rectus  muscle,  either  going  directly  through  it  or  drawing  it  to  one  side 
(Fig.  425).  In  McBurney's  operation  the  external  oblique  is  split  in  the  direction 
of  its  fibres  and  the  internal  oblique  and  transversalis  are  parted  upward  and  inward 
in  the  direction  of  their  fibres,  thus  making  a  square  hole  through  which  the  appendix 
is  removed.  The  writer  {Attnals  of  Surgery,  Jan.  1906,  p.  106)  uses  a  transverse 
incision  with  its  centre  over  the  linea  semilunaris  opposite  to  or  2.5  cm.  (i  in.) 
above  the  anterior  superior  spine.  The  sheath  of  the  rectus  is  divided  transversely 
and  the  muscle  displaced  toward  the  median  line.     The  outer  portion  of  the  incision 


THE    LARGE    INTESTINE. 


415 


runs  slightly  oblique  to  the  fibres  of  the   external  oblique  and  almost  exactly  in 
the  direction  of  the  fibres  of  the  internal  oblique  and  transversalis  (Fig.  426). 

As  soon  as  the  peritoneum  is  opened  the  omentum  may  present  itself.  This  is 
to  be  displaced  to  the  left.  Some  coils  of  small  intestine  if  present  are  to  be  pushed 
also  to  the  left.     The  intestine  then  presenting  will  be  the  colon  or  caecum,  because 


Fibres  of  the  external  oblique 

Fibres  of  the  internal  oblique 

Fibres  of  the  transversalis 


Anterior  part  of  sheath  of  the  rectus 

Rectus  muscle 

Posterior  part  of  the  sheath  of  the 

rectus 


Fig.  425. — Incisions  used  for  operations  on  the  appendix.  The  longitudinal  operation  passes  through  and 
separates  the  fibres  of  the  rectus  muscle.  The  oblique  oiJcration  (that  of  McBurney)  separates  the  external  oblique, 
internal  oblique,  and  transversalis  muscles  in  the  direction  of  their  fibres. 

it  is  fastened  to  the  posterior  wall  and  cannot  be  moved  away.  The  longitudinal 
bands  will  also  identify  it.  Another  way  is  to  pass  the  finger  down  the  inside  of  the 
abdominal  wall  and  the  floor  of  the  iliac  fossa  and  bring  up  the  caecum.  Always 
work  from  the  outer  toward  the  inner  side,  because  (see  Fig.  422)  the  ascending 


Ileum 

Rectus  muscle  drawn  inward 


Sheath  of  rectus  opened 

Fibres  of  the  internal  oblique  and 
"transversalis  muscles 
-External  oblique  aponeurosis 


Fig.  426. — Author's  incision  for  appendicitis. 


The  CJBCum  has  been  lifted  out  of  the  wound,  bringing  with  it  the 
appendix. 


colon  and  caecum  almost  always  lie  against  the  abdominal  wall  on  the  surface  of  the 
iliacus  muscle  above  the  outer  half  of  Poupart's  ligament. 

The  caecum  is  to  be  drawn  up  and  turned  toward  the  head.  The  longitudinal 
bands,  all  of  which  lead  to  the  appendix,  are  to  be  followed  down  over  the  caecum 
until  the  appendix  is  reached.  If  the  bands  are  not  visible,  identify  the  ileocaecal 
junction  and  about  2  cm.  (3/^  in.)  or  less  below  and  behind  it  will  be  the  root  of  the 


4l6 


APPLIED    ANATOMY. 


appendix;  its  tip  may  be  anywhere.  It  can  be  enucleated  from  its  root  out  to  its  tip. 
A  ligature  is  to  be  placed  around  the  meso-appendix  because  the  appendicular  artery, 
especially  its  recurrent  branch,  may  bleed  quite  freely.  The  root  of  the  appendix 
may  sometimes  be  at,  instead  of  below,  the  ileocaical  junction.  The  small  intestine 
and  caecum  almost  always  overlie  the  appendix. 

THE   COLON. 

The  ascending  colon  lies  in  contact  w^ith  the  anterior  abdominal  wall  from  its 
lower  end  to  above  the  iliac  crest ;  here  it  dips  down  to  lie  on  the  kidney  and 
form  the  hepatic  flexure  above  (Fig.  427).  At  this  point  some  of  the  coils  of  the 
small  intestine  may  lie  in  front  of  the  hepatic  flexure,  between  the  beginning  of  the 
transverse  colon  above  and  the  ending  of  the  ascending  colon  below.     The  ascend- 


Transverse  colon 


Colica  media  artery 


Colica  dextra  artery. 


Hepatic  flexu 

Cut  edge  of 
mesentery. 


Ascending  colon. 

Caecum' 
lleocaecal  junction,—' 

Base  of  appendix- 


-'  Appendices  epiploicae 


Superior  mesenteric 
artery 


Duodenojejunal 

! flexure 

Inferior  mesenteric 
artery 

Splenic  flexure 

Colica  sinistra  artery 

Descending  colon 

Pelvic  colon 

Tliac  colon 

Ileum 


Fig.  427. — View  of  the  interior  of  the  abdomen;  the  mesentery  has  been  cut,  the  small  intestines  removed,  and 
the  transverse  colon  turned  upward.     The  pelvic  colon  and  iliac  colon  together  form  the  sigmoid  flexure. 


ing  colon  lies  on  the  quadratus  lumborum  muscle  and  kidney  behind  and  has  the  psoas 
to  its  inner  side.  It  has  no  mesentery  or  peritoneum  on  its  posterior  surface  in  64 
per  cent,  of  the  cases  (Treves)  and  in  tumors  of  the  kidney  it  may  be  pushed  forward 
and  across  their  anterior  surface.      This  is  a  point  to  be  remembered  in  diagnosis. 

The  transverse  colon  passes  diagonally  up  and  to  the  left  across  the  abdo- 
men. It  starts  at  the  hepatic  flexure  on  the  under  surface  of  the  liver  to  the  outer 
side  of  the  gall-bladder.  It  runs  parallel  with  the  lower  edge  of  the  liver  and  stom- 
ach and  its  lower  border  may  reach  nearly  or  quite  to  the  level  of  the  umbilicus. 
The  great  omentum  passes  over  the  transverse  colon,  so  that  to  see  the  latter  it  is 
necessary  to  raise  the  omentum  and  look  on  its  under  surface.     The  omentum  as  it 


THE    LIVER.  417 

passes  from  the  colon  to  the  stomach  forms  the  gastrocolic  omentum  and  the  two 
organs  may  be  either  close  together  or  some  distance  apart.  The  transverse  colon 
instead  of  running  upward  and  to  the  left  may  form  a  large  curve  downward,  reach- 
ing almost  to  the  pelvis.  In  cases  of  dilatation  and  descent  (ptosis)  of  the  stomach 
the  transverse  colon  descends  with  it.  The  transverse  mesocolon  passes  backward 
and  one  layer  goes  up  and  covers  the  pancreas  vvhile  the  other  goes  down  to  the 
mesentery.  Its  importance  in  gastro-enterostomy  has  been  pointed  out  (page  406). 
Tumors  and  cysts  of  the  pancreas  may  push  forward  above  it,  or  below  it,  or  it  may 
cross  directly  over  the  surface  of  the  growth. 

The  descending  colon  at  its  commencement  at  the  splenic  flexure  is  much 
higher  and  more  deeply  situated  than  is  the  hepatic  flexure.  It  follows  the  stomach 
upward  and  backward  and  lies  against  the  spleen.  From  here  it  descends  and  is 
entirely  covered  by  small  intestine,  the  sigmoid  flexure  coming  to  the  front  in  the  left 
iliac  fossa.  The  descending  colon  is  much  smaller  in  size  than  the  ascending  colon, 
and  like  it  in  the  majority  (two-thirds)  of  cases  has  no  mesentery.  In  doing  a  colos- 
tomy through  the  loin,  the  external  border  of  the  quadratus  lumborum  muscle  is  the 
guide  to  the  descending  colon.  It  lies  1.25  cm.  (^  in.)  behmd  the  middle  of  the 
crest  of  the  ilium. 

Sigmoid  Flexure. — The  sigmoid  flexure  is  composed  of  two  parts:  one  in  the 
iliac  fossa,  called  the  iliac  colon,  and  the  other  in  the  pelvis,  called  the  pelvic  colon, 
or  omega  loop  of  Treves. 

The  iliac  colon  is  about  12.5  to  15  cm.  (5  to  6  in.)  long,  and  runs  from  the 
crest  of  the  ilium  to  the  inner  edge  of  the  iliopsoas  muscle.  It  has  no  mesentery  in 
90  per  cent,  of  the  cases  (Jonnesco),  and  usually  comes  into  contact  with  the  ab- 
dominal wall  to  the  inner  side  of  the  anterior  superior  spine  sometimes  as  far  down 
as  the  middle  of  Poupart's  ligament.  In  doing  an  inguinal  colostomy  this  is  the 
portion  of  the  colon  it  is  desired  to  find.  It  is  then  followed  down  until  a  part  is 
reached  which  has  sufficient  mesentery  to  allow  of  its  being  drawn  out  of  the  wound. 

The  pelvic  colon  is  about  40  to  42.5  cm.  (16  to  17  in.)  long  and  runs  from  the 
edge  of  the  psoas  muscle  to  the  level  of  the  third  sacral  vertebra.  It  makes  a  large 
horseshoe-shaped  loop,  from  which  it  was  named  by  Treves  the  omega  Joop,  and  has 
a  mesentery  from  3  to  8  cm.  {1%  to  3)^  in.)  long.  The  length  of  the  loop  as  well 
as  its  mesentery  and  its  position  all  vary  considerably.  Its  terminal  portion  usually 
runs  longitudinally  down  to  end  in  the  rectum,  but  its  intervening  portion  may  pass 
over  the  bladder  to  the  right  side,  or  high  above  the  symphysis,  or  even  extend 
well  up  in  the  abdominal  cavity.  On  the  under  or  left  side  of  the  loop  between  its 
branches  is  the  intersigmoid  fossa  (see  Fig.  422,  page  410)  ;  sometimes  it  forms  a 
constricted  pouch  in  which  a  knuckle  of  intestine  has  been  known  to  become 
strangulated. 

THE   LIVER. 

The  liver  is  wedge-shaped  and  has  three  surfaces.  These  are  superior,  inferior, 
and  posterior.  The  posterior  forms  the  base  of  the  wedge  and  its  anterior  edge  is 
the  apex.  The  liver  is  divided  into  five  lobes  by  five  primary  fissures  and  has 
five  ligaments  (Fig.  428). 

The  lobes  of  the  liver  are:  (i)  left,  (2)  right,  (3)  quadrate,  (4)  Spigelian, 
(5)  caudate.  The  left  lobe  is  one-sixth  the  size  of  the  right.  It  comprises  that  part 
to  the  left  of  the  falciform  ligament  above  and  the  umbilical  and  ductus  venosus  fis- 
sures below.  The  right  lobe  comprises  that  part  to  the  right  of  the  falciform  ligament 
above  and  the  fissures  of  the  gall-bladder  and  vena  cava  below.  The  quadrate  lobe 
is  the  anterior,  small,  square-shaped  lobe  between  the  fissure  of  the  gall-bladder  on  the 
right  and  the  umbilical  fissure  on  the  left.  It  extends  from  the  anterior  edge  back 
to  the  portal  fissure.  The  Spigelian  lobe  is  best  seen  posteriorly,  extending  from  the 
vena  cava  on  the  right  to  the  fissure  of  the  ductus  venosus  on  the  left.  The  caudate 
lobe  or  process  is  the  name  given  to  the  liver  tissue  running  from  the  lower  end  of 
the  Spigelian  lobe  to  the  right  lobe.  It  passes  behind  the  portal  fissure  and  between 
it  and  the  vena  cava.  RicdeV s  lobe  is  the  name  given  to  an  abnormal,  tongue-like 
projection  of  liver  tissue  from  its  anterior  edge,  which  may  extend  downward  either 
over  the  gall-bladder  or  external  to  it.  Mayo  Robson  has  seen  it  extend  to  the  caecal 
27 


4i8 


APPLIED    ANATOMY. 


region,  and  an  inflamed  gall-bladder  being  directly  beneath  caused  pain  to  be  experi- 
enced at  McBurney's  point.  This  condition  is  liable  to  be  mistaken  for  appendicitis. 
The  fissures  of  the  liver  are  best  understood  by  examining  its  under  surface, 
where  they  can  be  seen  arranged  in  the  form  of  the  letter  H.  They  are  as  follows:  ( i ) 
The  tmibilical fissure,  running  from  the  umbilical  notch  on  the  anterior  edge  to  the  left 
end  of  the  portal  (transverse)  fissure;  it  contains  the  round  ligament.  (2)  T\\q  fissure 
of  the  ductus  venosus,  running  upward  from  the  left  end  of  the  portal  fissure  be- 
tween the  left  and  Spigelian  lobes;  it  contains  the  remains  of  the  fetal  ductus  venosus. 


Right  lateral  ligament- 


Right  lobe 


Left  lateral  or  triangular 
ligament 


Left  lobe 


Falciform  ligament 
Round  ligament 


Fissure  of  the  gall-bladder 
Fig.  428. — View  of  the  anterior  and  upper  surfaces  of  the  liver. 


(3)  The  fissure  of  the  gall-bladder,  separating  the  quadrate  from  the  right  lobe  and 
ending  at  the  right  extremity  of  the  portal  fissure;  in  it  lies  the  gall-bladder.  (4) 
The  fissure  of  the  vena  cava,  between  the  Spigelian  and  right  lobes,  lodging  the  vena 
cava.  (5)  The  portal  fissure, — this  forms  the  transverse  bar  of  the  H.  Its  left  end 
receives  the  umbilical  and  ductus  venosus  fissures  and  its  right  end  the  fissures  of  the 
gall-bladder  and  vena  cava.  It  contains  the  portal  vein,  hepatic  artery,  hepatic  duct, 
nerves,  and  lymphatics;  attached  to  its  sides  is  the  lesser  or  gastrohepatic  omentum. 
The  portal  fissure  is  also  called  the  transverse  fissure,  and  the  name  longitudinal 

Cystic 
Vena  cava         duct  Caudate  lobe  or  process 


Spigelian  lobe 


Left  lobe 


Gastric  impression 
Fissure  of  the  ductus  venosus 

Portal  vein 

Hepatic  artery 

Umbilical  fissure 

Round  ligament 


Coronary  ligament 
Right  lobe 

Renal  impression 
Duodenal  impression 

■Colic  impression 


Portal  fissure 

Quadrate  lolje 


Gall-bladder 
Fig.  429. — View  of  the  posterior  and  inferior  surfaces  of  the  liver. 

fissure  is  sometimes  applied  to  the  combined  umbiHcal  and  ductus  venosus  fissures. 
(In  the  recent  anatomical  nomenclature  these  fissures  are  called  fossae.)  (Fig.  429.) 
The  ligaments  of  the  liver  are  five  in  number:  (i)  the  coronary,  (2)  the 
triangular,  (3)  the  falciform,  (4)  the  round,  and  (5)  the  ligament  of  the  ductus 
venosus.  The  coronary  ligame7it  surrounds  the  posterior  surface  which  is  not 
covered  by  peritoneum.  It  is  4  to  6  cm.  (i^  to  2%  in.)  wide  and  extends  from 
the  vena  cava  7.5  to  10  cm.  (3  to  4  in.)  to  the  right,  terminating  in  a  pointed 
end  which  has  been  called  the  right  lateral  ligament.     The  triangular  ligament,  also 


THE   LIVER. 


419 


called  the  left  lateral,  extends  as  far  to  the  left  of  the  falciform  ligament  as  the  coronary- 
does  to  the  right.  It  is  attached  to  the  diaphragm  in  front  of  the  oesophagus,  while 
the  coronary  is  attached  to  the  back  of  the  diaphragm.  The  falciform  ligament 
starts  near  the  umbilicus,  passes  to  the  umbihcal  notch  of  the  liver  2.5  to  4  cm.  (i  to 
xyi  in. )  to  the  right  of  the  median  line  and  thence  over  the  top  of  the  liver  to  near 
its  posterior  edge,  where  it  blends  in  front  of  the  vena  cava  on  the  right  side  with  the 
coronary  ligament  and  on  the  left  with  the  triangular  ligament.  The  roimd  ligament 
is  the  round  cord  in  the  free  edge  of  the  falciform  ligament  which  runs  from  the 
umbilicus  to  the  umbilical  notch  and  thence  to  the  portal  fissure  to  join  the  left  branch 
of  the  portal  vein.  It  is  the  remains  of  the  fetal  umbilical  vein.  The  ligament  of  the 
ductus  venosiis  runs  from  the  left  branch  of  the  portal  vein  to  the  vena  cava  in  the 
fissure  of  the  ductus  venosus.  The  ductus  venosus,  like  the  umbilical  vein,  becomes 
obliterated  at  birth. 

Position  of  the  Liver. — The  liver  rises  to  the  fourth  costal  interspace  on  the 
right  side,  to  or  slightly  above  the  xiphosternal  junction  in  the  midline,  and  the  lower 
border  of  the  fifth  rib  on  the  left  side,  to  its  extremity,  just  beyond  the  apex  of  the 
heart,  at  the  lower  border  of  the  sixth  rib.  Its  lower  border  passes  from  this  point  to 
the  eighth  left  cartilage,  crosses  the  middle  line  about  midway  between  the  xiphoid 


Suprarenal  gland 


Vena  cava 


Kidney 


First  portion 
of  duodenum-- 


Second  portion 
of  duodenum 


Portal  vein 
Hepatic  artery 

Common  bile-duct 


^Pvlorus 


Fig.  430. — The  bed  of  the  liver. 


Gastrocolic  omentum 


Right  gastro-epiploic  artery 
The  liver  has  been  removed  to  show  the  surrounding  structures. 


articulation  and  umbilicus  to  the  ninth  right  costal  cartilage,  and  thence  follows  the 
edge  of  the  ribs  posteriorly,  being  about  2.5  cm.  (i  in.)  lower  in  women.  The 
upper  limits  of  its  percussion  dulness  are  the  upper  border  of  the  sixth  rib  in  the 
right  mammillary  line,  the  eighth  in  the  axillary,  and  the  tenth  in  the  scapular. 

Relations  of  the  Liver. — The  superior  surface  lies  in  contact  with  the 
diaphragm,  except  the  portion  extending  about  7.5  cm.  (3  in.)  below  the  xipho- 
sternal junction  in  the  median  line  and  sometimes  the  small  projecting  edge  beyond 
the  ribs,  which  lies  in  contact  with  the  abdominal  wall.  The  posterior  sjirface  lies 
over  the  tenth  and  eleventh  thoracic  vertebrae,  the  crura  of  the  diaphragm,  the 
oesophagus,  aorta,  vena  cava,  and  right  suprarenal  gland.  The  inferior  surface  to 
the  left  rests  on  the  cardiac  end  and  upper  surface  of  the  stomach  and  gastrohepatic 
omentum.  Beneath  the  quadrate  lobe  is  the  pylorus  and  beginning  of  the  duo- 
denum. Beneath  the  caudate  lobe  is  the  forameii  of  IVinslotc,  of  which  it  forms 
the  upper  boundary.  Farther  to  the  right  are  the  depressions  for  the  hepatic  flexure 
of  the  colon  and  the  right  kidney  and  suprarenal  gland  (Fig.  430). 

The  size  of  the  liver  varies,  being  small  in  atrophic  diseases  and  much  enlarged 
in  others;  therefore,  alterations  in  the  area  of  dulness  are  frequent.  It  moves  with 
respiration  and  sometimes  hangs  lower  than  normal  (ptosis). 


420  ^^^^^K-  APPLIED    ANATOMY.  ^^^^^^^™ 

Wounds  and  Injuries  of  the  Liver. — The  liver  is  frequently  ruptured  in 
falling  or  by  being  struck  by  some  body  from  without.  The  rupture  may  involve  its 
anterior  edge  or  upper  surface.  In  all  examinations  it  should  not  be  forgotten  that 
the  right  and  left  sides  are  separated  completely  by  the  falciform  ligament.  On 
account  of  the  walls  of  the  vessels  being  imbedded  in  the  liver  tissue  they  do  not 
readily  collapse  and  hemorrhage  is  often  fatal.  Rupture  of  the  posterior  nonperi- 
toneal  surface  is  not  so  dangerous  as  elsewhere. 

Abscesses  may  be  either  one  or  two  large  ones  or  multiple  small  ones. 
Pus  on  the  upper  surface  of  the  liver,  between  it  and  the  diaphragm,  is  called  S2(d- 
diaphragviatic  abscess.  It  may  originate  either  from  the  liver  or  other  viscera  below, 
or  the  lung  and  pleura  above.  Maydl  gives  gastric  ulcer  as  the  most  frequent  cause 
and  then  affections  of  the  intestines  and  appendix ;  we  have  seen  it  arise  from  calculous 
disease  of  the  kidney.  The  pus  may  discharge  outward  between  the  ribs,  or  upward 
into  the  pleural  cavity,  lung,  or  pericardial  sac.  In  incising  for  subdiaphragmatic 
•abscess  the  tenth  rib  in  the  axillary  line  can  be  resected  without  opening  the 
pleura,  but  if  the  eighth  or  ninth  is  chosen  the  pleural  sac  may  be  opened  and 
the  two  layers  of  pleura  should  be  stitched  together  before  the  incision  through  the 
diaphragm  into  the  abscess  cavity  is  made.  If  the  abscess  points  at  the  inferior 
surface  it  may  break  into  the  stomach,  duodenum,  or  colon.  It  may  be  reached  by 
an  incision  through  the  abdominal  walls  to  the  right  of  the  median  line.  The  posi- 
tion of  the  falciform  ligament,  about  4  cm.  ( i  )4  in. )  to  the  right  of  the  median  line, 
should  be  remembered,  and  if  the  left  lobe  of  the  liver  is  to  be  treated  the  inci- 
sion should  be  made  to  the  left  of  the  ligament. 

Multiple  abscesses  are  started  in  the  liver  by  conveyance  of  infection  through  the 
portal  vein,  as  occurs  in  appendicitis,  or  by  direct  extension  up  the  common  duct 
from  the  intestine,  or  from  an  inflamed  gall-bladder  or  bile-ducts  through  the  hepatic 
duct  and  its  ramifications. 

Portal  Obstruction. — The  veins  of  the  portal  system  have  no  valves.  The 
portal  vein  is  formed  by  the  union  of  the  splenic  and  superior  mesenteric  veins 
and  the  gastric,  pyloric,  and  cystic  veins.  The  splenic  receives  the  blood  from  the 
spleen,  the  stomach,  and  pancreas,  the  descending  colon,  sigmoid  flexure,  and  rec- 
tum. The  superior  hemorrhoidal  vein  drains  the  rectum  and  empties  into  the  inferior 
mesenteric,  which  passes  into  the  splenic  and  finally  into  the  portal  vein.  The  supe- 
rior mesenteric  vein  drains  the  remainder  of  the  large  and  small  intestine. 

In  cirrhosis,  carcinoma,  and  occasionally  gall-stones,  the  flow  of  blood  through 
the  portal  vein  is  interfered  with ;  hence  arise  congestions  of  the  various  parts  which 
it  drains.  In  the  abdomen  ascites  is  produced  ;  the  distended  and  varicose  veins  of 
the  stomach  sometimes  rupture,  causing  haematemesis  ;  diarrhoea  may  occur,  and 
dilatation  of  the  hemorrhoidal  veins  produces  hemorrhoids. 

Especially  when  there  also  is  pressure  on  the  vena  cava  the  superficial  and  deep 
veins  of  the  abdominal  wall  become  enlarged  (see  page  380).  The  main  anasto- 
moses are  :  ( i )  between  the  gastric  (coronary)  vein  of  the  stomach  and  the  oesopha- 
geal veins  which  empty  into  the  vena  azygos  major;  (2)  between  the  epigastrics 
(superficial  and  deep)  below  and  the  terminal  branch  of  the  internal  mammary 
above;  (3)  between  the  epigastric  veins  and  portal  vein  through  the  para-umbilical 
vein  (caput  medusae,  page  380);  (4)  through  the  thoracico-epigastrica  between  the 
axillary  and  epigastric  (see  Fig.  392,  page  380)  ;  (5)  between  the  superior  hemor- 
rhoidal and  the  middle  hemorrhoidal,  emptying  into  the  internal  pudic. 

GALL-BLADDER  AND  BILIARY  PASSAGES. 

The  gall-bladder  lies  in  the  fissure  of  the  gall-bladder,  with  its  fundus  just  about 
level  with  the  edge  of  the  liver  and  its  body  pointing  inward,  upward,  and  backward; 
its  neck,  which  is  S-shaped,  is  near  the  right  end  of  the  portal  fissure.  It  is  7.5  cm. 
(3  in.)  long  and  2.5  to  3  cm.  (i  to  1^4^  in.)  in  diameter.  It  holds  one  to  one  and 
a  half  ounces.  Below,  it  rests  on  the  transverse  colon  and  first  part  of  the  duodenum. 
It  is  attached  to  the  liver,  but  not  very  strongly,  by  connective  tissue  and  the 
peritoneum.  According  to  Brewer  {Annals  of  Surgery,  1899,  vol.  xxix,  page  723) 
one-third  to  one-fourth  of  its  surface  is  uncovered  by  peritoneum :  in  5  cases  in  100 


THE    LIVER. 


421 


it  had  a  distinct  mesentery.  The  tip  (fundus)  of  the  gall-bladder  lies  in  contact  with 
the  abdominal  wall  at  the  tip  of  the  ninth  costal  cartilage,  where  the  right  linea 
semilunaris  strikes  the  costal  margin,  and  just  at  the  outer  edge  of  the  rectus  muscle, 
which  is  about  7.5  cm.  (3  in.)  from  the  median  line  (Fig.  431). 

Hepatic,  Cystic,  and  Common  Ducts. — The  hepatic  duct  is  formed  by  the 
union  of  the  right  and  left  branches  in  the  portal  fissure.  It  is  about  2.5  cm.  (i  in.) 
long  and  6  mm.  (  y^  in.  )  wide.  The  cystic  duct  is  smaller  in  diameter  than  the  hepatic 
and  3  to  4  cm.  (i  14^  to  i^  in.)  long  and  joins  it  as  it  emerges  from  the  portal  fissure. 
Both  the  neck  of  the  gall-bladder  and  the  cystic  duct  contain  constrictions  of  the 
mucous  membrane — Robson  and  Moynihan  call  them  valves — which  obstruct  the 
passage  of  a  probe  or  stone.  Hence  gall-stones  are  frequently  found  impacted  or 
lodged  in  the  neck  of  the  gall-bladder  or  somewhere  in  the  course  of  the  duct.  The 
cystic  artery  lies  above  the  duct.  The  common  duct  is  formed  by  the  union  of  the 
hepatic  and  cystic  ducts  at  the  edge  of  the  portal  fissure,  and  empties  into  the  duo- 
denum about  the  middle  of  its  second  portion  on  its  inner  wall.  It  is  7.5  cm.  (3  in.) 
long  and  6  mm.  (j^  in.)  or  more  in  width.      It  passes  almost  directly  downward. 


Gall-bladder 

Cystic  duct 

Foramen  of  Winslow 

Cut  end  of  duodenum 

Kidney 
Ampulla  of  Vater 


--- — Hepatic  duct 


"''^"ir*^ 


Pancreatic  duct 


.Opening  of  the  ducts  into  the 
secon  d  portion  of  the  duodenum 


,,^,f?!,^A/A,^"T'^*lf  ^'''^'■y  passages.  The  edge  of  tlie  liver  has  been  raised,  exposing  its  under  surface;  the  first 
and  blood- vessels"  antenor  surface  of  the  pancreas  has  been  removed,  exposing  the  common  bile-duct 

inclining  a  little  to  the  right,  between  the  folds  of  the  lesser  omentum,  in  front  of  the 
foramen  of  Winslow,  behind  the  first  portion  of  the  duodenum,  and  then  between 
the  pancreas  and  the  inner  wall  of  the  second  portion  of  the  duodenum.  It  is,  at 
this  part,  in  two-thirds  of  the  cases,  completely  surrounded  by  pancreatic  tissue.  '  As 
it  passes  through  the  duodenum,  which  it  pierces  obliquelv,  it  expands  into  the 
ampulla  of  Vater  and  receives  the  pancreatic  duct,  or  duct  of  IVirstmg.  Above,  it 
lies  direcdy  on  the  portal  vein,  with  the  hepatic  artery  to  its  left.  About  half  of  the 
duct,  3  to  4  cm._  (1 14:  to  1 1^  in.),  is  above  the  duodenum  and  half  behind  it. 

The  hepatic  artery  passes  along  the  upper  edge  of  the  pancreas,  to  which  it 
gives  branches;  it  then  gives  off  the  superior  pyloric  to  the  lesser  curvature  of  the 
stomach,  the  gastroduodenal  (see  page  403),  and  finally  right  and  left  terminal 
branches.  The  left  supplies  the  left  lobe  of  the  liver,  the  right  crosses  usually 
behind  but  sometimes  in  front  of  the  bile-ducts  and  terminates  in  the  right  iobe,  after 
first  giving  off  the  cystic  artery.  This  runs  between  the  cvstic  and  hepatic  ducts  and 
has  superficial  branches  which  ramify  on  the  surface  of  the  gall-bladder  and  deep 
branches  which  run  up  the  grooves  on  each  side  between  the  gall-bladder  and  liver. 


432  APPLIED   ANATOMY. 

It  is  these  branches  which  bleed  when  the  gall-bladder  is  removed.  One  of  the  deep 
arteries  may  be  much  larger  than  the  other  or  altogether  lacking.  Some  very  fine 
branches  come  directly  from  the  liver. 

Lymphatic  nodes  are  found  in  the  portal  fissure  and  accompanying  both  the 
common  and  cystic  ducts.      They  are  especially  involved  in  carcinoma. 

The  kidney  pouch  is  a  name  given  to  the  space  in  front  of  the  right  kidnev. 
The  foramen  of  Winslow  opens  into  it  from  the  left  and  the  abdominal  wall  is  to  its 
right.  The  liver  is  above  and  the  duodenum  and  transverse  colon  below.  Liquids 
from  the  lesser  peritoneal  cavity  and  bile-passages  flow  into  this  hollow,  which  can  be 
drained  by  a  tube  inserted  through  a  "stab-wound"  made  through  the  abdominal 
wall  just  to  the  outside  of  the  right  kidney. 

Gall-Stones. — These  and  carcinoma  are  the  main  affections  of  the  biliary  pass- 
ages. The  latter  is  almost  always  secondary  to  pyloric  cancer  and  involves  the  lymph- 
atic nodes ;  metastatic  deposits  may  also  exist  in  the  liver  itself.  The  diagnosis 
between  the  two  affections  is  sometimes  difficult.  Gall-stones  are  most  frequent  in 
the  gall-bladder,  next  in  the  common  duct,  and  lastly  in  the  hepatic  duct.  Obstruc- 
tive symptoms  are  not  often  observed  from  gall-stones  in  the  hepatic  duct  alone. 
Obstruction  of  the  common  duct  causes  jaundice,  but  this  is  rare  in  obstruction  of  the 
cystic  duct  ;  practically,  jaundice  is  only  seen  in  obstruction  of  the  common  duct. 
Gall-stones  usually  form  in  the  gall-bladder  and,  as  the  cystic  duct  is  smaller  than  the 
common  duct,  if  a  stone  gets  out  of  the  former  it  is  frequently  passed  into  the  intes- 
tine. On  account  of  the  contracted  opening  of  the  common  duct  into  the  duodenum, 
stones  are  liable  to  be  retained  in  the  ampulla  of  Vater.  This  causes  a  damming  back 
of  the  bile,  and  the  common  duct  increases  to  the  size  of  a  finger.  Very  large  gall- 
stones may  cause  ulceration  into  the  duodenum  or  colon  or  may  press  on  the  portal 
vein  and  vena  cava,  and  produce  ascites.  In  operating  for  gall-stones.  Mayo  Robson 
incised  through  the  middle  of  the  right  rectus  muscle  and  prolonged  the  upper  part 
along  the  edge  of  the  ribs  to  the  outer  side  of  the  ensiform  cartilage.  Where  more 
room  was  desired  Bevan  added  a  transverse  cut  outward  from  its  lower  end.  Kocher 
made  a  curved  incision  4  cm.  (i^  in.)  below  the  edge  of  the  ribs  (see  page  382). 
In  order  to  make  the  liver  project  a  hard  roll  is  placed  beneath  the  back.  To  bring 
the  gall-ducts  to  the  surface  the  liver  is  dragged  down  and  its  edge  turned  up  over 
the  upper  extremity  of  the  wound.  The  gall-bladder  can  be  drawn  out  and  this 
straightens  the  curves  in  the  cystic  duct.  By  placing  one  or  two  fingers  in  the  fora- 
men of  Winslow  the  thumb  can  palpate  the  cystic  and  the  common  duct  until  it 
disappears  behind  the  duodenum.  Gall-stones  in  the  second  (retroduodenal)  portion 
of  the  duct  or  in  the  ampulla  of  Vater  can  often  be  felt  through  the  walls  of  the  duo- 
denum. If  it  is  desired  to  gain  access  to  this  portion  of  the  duct,  the  peritoneum  on 
the  outer  side  of  the  second  portion  of  the  duodenum,  binding  it  to  the  posterior 
abdominal  wall,  must  be  divided.  The  duodenum  is  then  turned  to  the  left  and  the 
common  duct  followed  down  if  necessary  through  the  pancreas  to  the  ampulla  of  Vater. 
Stones  impacted  in  the  ampulla  of  Vater  can  be  removed  by  incising  the  front  of  the 
second  portion  of  the  duodenum  and  then  cutting  down  on  the  stone  through  the 
papilla.  In  some  cases  it  may  be  impossible  to  pass  a  probe  down  the  cystic  duct 
owing  to  its  being  caught  by  the  valve-like  folds  of  the  mucous  membrane.  In 
removing  the  gall-bladder,  bleeding  will  be  less  if  the  cystic  artery  be  first  clamped. 
If  this  is  not  possible,  then  the  bleeding  will  occur  from  the  branches  on  one  or  both 
sides  of  the  gall-bladder.  The  peritoneum  is  to  be  cut  through,  not  torn.  Bleeding 
from  the  liver  substance  is  slight  and  readily  stopped  by  pressure.  In  incising  the 
common  duct  for  calculi  the  relation  of  the  portal  vein  behind  and  the  hepatic 
artery  to  the  left  should  be  remembered.  These  can  be  avoided  by  cutting  down  on 
the  calculus. 

THE   PANCREAS. 

The  pancreas  is  composed  of  two  portions  joined  at  right  angles  to  each  other. 
Together  they  measure  about  20  cm.  (8  in.).  It  is  divided  into  a  head,  neck,  body, 
and  tail.  The  neck  is  about  2  cm.  (^  in.)  broad,  while  the  head  and  body  are 
each  about  3  cm.  {i}(  in.).  The  head  is  about  5  to  6.25  cm.  (2  to  2^  in.)  long 
and  lies  parallel  to  the  vertebral  column  on  its  right  side.     The  body  is  about  12.5 


THE    PANXREAS. 


423 


cm.  (5  in. )  long  and  runs  transversely  from  the  first  portion  of  the  duodenum  across 
to  the  spleen.  The  flexure  joining  the  head  and  body  constitutes  the  neck.  It  is 
2.5  cm.  (i  in.)  long.  The  tail  is  simply  the  extremity  of  the  body  ;  this  is  omitted 
in  some  descriptions.  The  body  crosses  the  first  lumbar  vertebra,  while  the  head 
lies  on  the  right  side  of  the  second  and  third  (Fig.  432). 

Pancreatic  Ducts. — The  pancreas  has  two  ducts,  a  main  one  called  the  pan- 
creatic duct,  or  duct  of  Wirsiuig,  and  an  accessory  one  called  the  duct  of  Santorini. 
The  duct  of  Wirsung  runs  nearly  the  whole  length  of  the  gland,  and,  bending  some- 
what downward  at  the  neck  and  joining  the  common  bile-duct  at  the  ampulla  of 
Vater,  pierces  the  duodenum  obliquely  and  empties  in  a  common  orifice  on  its 
mucous  surface.  It  is  3  to  4  mm.  (  yi  to  y^  in. )  in  diameter  at  its  termination.  The 
accessory  duct  of  Santorini  comes  mainly  from  the  lower  portion  of  the  head  of  the 
pancreas  and  empties  separately  in  the  duodenum  2  cm.  (^  in.  )  above  and  a  little 
anterior  to  the  biliary  papilla.  It  communicates  with  the  duct  of  Wirsung  in  the 
substance  of  the  pancreas. 

Relations. — Posteriorly,  the  head  lies  on  the  vena  cava  while  the  body  crosses 
the  aorta,  venal  vessels,  suprarenal  gland,  and  left  kidney.  Anteriorly,  it  is  covered 
with  peritoneum  and  on  it  lies  the  stomach ;  inferiorly,  is  the  attachment  of  the  trans- 


Portal  vein 


Hepatic  artery 


Coeliac  axis 

Gastric  artery 

Gastroduodenal 
artery 

Spleen 
Splenic  artery 


Descending  colon 


Pancreas 


Superior  mesenteric 
vessels 


Common  bile-ductf^ 

Second  portion 
of  duodenum 


riepatic  flexure 
of  colon 


Pig.  432. — The  pancreas  and  spleen. 


verse  mesocolon,  beneath  which  comes  the  duodenojejunal  flexure.  Immediately  to 
the  right  of  this  flexure  and  between  it  and  the  head  of  the  pancreas  issue  the  superior 
mesenteric  vessels.      At  the  extreme  left  is  the  splenic  flexure  of  the  colon. 

Pancreatic  Cyst  and  Abscesses. — The  pancreas  is  the  subject  of  inflam- 
mation (hemorrhagic)  which  may  cause  necrosis  and  abscess;  it  also  is  affected  with 
cysts  and  new  growths.      Calculus  may  also  occur. 

Suppuration  may  produce  a  sub-diaphragmatic  abscess  or  perforate  the  dia- 
phragm and  form  an  empyema.  In  cases  of  abscess  protruding  anteriorly,  instead 
of  opening  through  the  peritoneum  in  front,  the  pus  may  be  evacuated  through  a 
posterior  incision  made  in  the  right  or  left  costovertebral  angle.  If  the  pus  has  been 
evacuated  through  an  anterior  incision  the  finger  may  be  introduced  into  the  abscess 
cavity  and  used  as  a  guide  for  a  posterior  incision. 

Pancreatic  growths  tend  to  project  forward  in  one  of  three  general  directions — 
viz. :  (i)  between  the  liver  above  and  the  stomach  below;  (2)  between  the  stoir.ach 
above  and  the  transverse  colon  below;  (3)  below  the  transverse  colon.  The  second 
is  the  most  frequent.  When  the -enlargement  comes  forward  opposite  the  attach- 
ment of  the  transverse  mesocolon  it  may  grow  between  the  layers  of  the  mesocolon 
and  push  the  transverse  colon  in  front  of  it  instead  of  going  below  or  above  it.  After 
the  cyst  has  been  evacuated  it  may  be  stitched  to  the  edges  of  the  incision  anteriorly 
and  a  counter  opening  made  posteriorly  on  the  left  side  beneath  the  twelfth  rib. 


424  '^^^^H       APPLIED    ANATOMY. 


THE  SPLEEN. 

The  spleen  lies  high  up  in  the  left  posterior  corner  of  the  abdomen  in  contact 
with  the  diaphragm.  It  follows  the  direction  of  the  tenth  rib,  being  covered  by  the 
ninth,  tenth,  and  eleventh  ribs  and  extending  from  a  point  4.5  to  5  cm.  (i  J^  to  2  in.) 
external  to  the  median  line  posteriorly  to  the  midaxillary  line  anteriorly.  Its  upper 
end  is  opposite  the  tenth  dorsal  vertebra,  or  ninth  spine  (see  Fig.  433). 

Relations. — It  has  four  surfaces:  a  posterior  one,  which  lies  in  contact  with 
the  diaphragm;  an  anterior  one  toward  the  stomach;  an  inferior  small  one,  resting 
on  the  splenic  flexure  of  the  colon;  and  an  internal  one,  in  contact  with  the  left 
kidney  at  its  upper  anterior  portion.  The  hilum  is  on  its  anterior  or  gastric  surface 
and  posterior  to  it  is  a  depression  in  which  is  lodged  the  tail  of  the  pancreas. 

Ligaments. — The  spleen  is  covered  with  peritoneum  except  at  the  hilum, 
which  is  on  its  anterior  surface  ;  here  two  ligaments  are  given  off — a  posterior  one.  the 
lie?iorenal,  going  from  the  spleen  to  the  kidney  and  containing  the  blood-vessels, 
and  an  anterior  one,  \k\Q.  g astro sple^iic  (also  called  omentum)  going  to  the  stomach. 
The  lienophrenic  ligament  (suspensory  ligametd)  runs  from  the  left  crus  of  the 
diaphragm  to  the  upper  inner  edge  of  the  spleen  and  blends  with  the  two  former 
ligaments.  These  three  ligaments  form  a  pedicle  from  which  the  spleen  swings,  and 
it  is  by  their  stretching  that  the  spleen  at  times  descends  and  is  detected  below 
the  edge  of  the  ribs.  A  fourth  ligament,  the  phre^iocolic  (costocoh'c)  runs  from  the 
diaphragm  opposite  the  tenth  and  eleventh  ribs  to  the  splenic  flexure  of  the  colon. 
The  upper  surface  of  the  colon  is  concave,  forming  a  fossa  (splenic  fossa)  in  which 
the  spleen  rests  and  which,  of  course,  aids  in  supporting  it. 

Splenic  Enlargement. — The  spleen  is  enlarged  in  many  diseases,  such  as 
malaria,  leukaemia,  typhoid  fever,  and  others.  This  enlargement  is  to  be  detected  by 
palpation  and  percussion.  The  normal  spleen  lies  under  the  ribs,  therefore  it  can  be 
palpated  only  when  it  enlarges  and  projects  beyond  the  costal  margin  or  when  its 
pedicle  (ligaments)  becomes  stretched  and  allows  it  to  wander  down.  Normal 
percussion  dulness  extends  anteriorly  to  the  midaxillary  line ;  posteriorly  it  merges 
into  the  kidney  dulness  and  cannot  be  limited.  From  above  down  the  dulness  would 
be  from  the  ninth  to  the  eleventh  rib  in  the  posterior  axillary  line. 

'Wounds  of  the  Spleen. — -The  upper  portion  of  the  spleen  rises  as  high  as 
the  tenth  dorsal  vertebra  or  ninth  spine ;  as  the  lung  posteriorly  descends  at  least  one 
vertebra  lower  and  the  pleura  still  another  lower,  it  follows  that  a  penetrating  wound 
entering  the  ninth  costal  interspace  in  the  line  of  the  angle  of  the  scapula  would 
wound  first  the  pleura,  then  the  lung,  then  the  diaphragm,  then  the  spleen,  and 
finally  the  stomach.  If  it  entered  one  interspace  below — the  tenth — it  would  open 
the  pleural  cavity  but  would  probably  escape  the  edge  of  the  lung. 

THE    KIDNEYS. 

The  kidneys  when  normal  are  about  12  cm.  {^%  in.)  long,  6  cm.  (^2%  in.) 
broad  and  3  cm.  ( i  ^  in. )  thick.  The  right  is  the  thicker  and  the  left  a  little  the 
longer. 

They  lie  in  the  lumbar  regions  under  the  lower  portion  of  the  thoracic  wall. 
Their  upper  ends  are  nearer  the  midline  than  the  lower  and  the  inner  edges  point 
forward  and  inward,  thus  one  surface  is  antero-external  and  the  other  postero- 
internal. 

Relations  to  the  Surface. — Viewed  posteriorly  the  right  kidney  has  its  upper 
edge  opposite  the  eleventh  dorsal  spine  and  the  lower  edge  of  the  eleventh  rib. 
Its  lower  edge  is  opposite  the  upper  edges  of  the  third  lumbar  spine  and  vertebral 
body  and  about  4  cm.  (i^  in.)  above  the  highest  point  of  the  crest  of  the  ileum, 
which  is  opposite  the  fourth  spine  (Fig.  433).  The  left  kidney  is  usually  1.25  cm. 
{]4.  in. )  higher,  but  being  a  little  longer  than  th^  right,  its  lower  limit  may  not  be 
quite  that  much  higher.  The  kidney  is  slightly  lower  in  women  and  children  than 
in  men.  The  inner  border  reaches  10  cm.  (4  in.)  and  the  hilum  4  to  5  cm.  (i}4  to 
2  in. )  from  the  median  line,  the  latter  being  in  front  of  the  interval  between  the  first 


THE    KIDNEYS. 


425 


and  second  lumbar  spines  (H.  J.  Stiles).  Viewed  anteriorly,  the  lower  edge  of  the 
right  kidney  is  2.5  cm.  (i  in.)  above  a  transverse  line  through  the  umbilicus,  the 
left  being  a  little  higher.  The  upper  edge  is  opposite  approximately  the  tip  of  the 
ensiform  cartilage.  The  upper  end  approaches  within  3  cm.  (i}(  in.)  of  the  median 
line.  About  two-thirds  of  the  kidney  lies  to  the  inner  side  and  one-third  to  the 
outer  of  a  line  drawn  longitudinally  through  the  middle  of  Poupart's  ligament.  The 
hilum  would  be  4  to  5  cm.  ( i  ^  to  2  in. )  out  from  the  middle  of  a  line  joining  the 
upper  extremities  of  the  two  semilunar  lines. 

Deep  Relations. — The  posterior  surface  at  its  upper  portion  rests  on  the 
diaphragm;  beneath,  its  lower  portion,  from  within  out,  rests  on  the  psoas,  quadratus 
lumborum,  and  transversalis  muscles.  Between  the  kidney  and  the  quadratus  lum- 
borum  run  the  last  thoracic,  the  iliohypogastric,  and  the  ilio-inguinal  nerves.  The 
transversalis  fascia  as  it  lea\'es  the  body  of  the  first  lumbar  vertebra  arches  over  the 
psoas  muscle,  forming  the  internal  arcuate  ligament,  and  is  attached  to  the  trans- 


Colon 
Quadratus  lumborum 


Fig.  433. — Posterior  view,  showing  the  relations  of  the  spleen  and  kidneys. 

verse  process  of  the  first  lumbar  vertebra.  It  then  proceeds  out  over  the  quadratus 
lumborum  to  be  attached  to  the  outer  portion  of  the  twelfth  rib,  forming  the  external 
arcuate  ligament.  It  then  blends  with  the  tendon  or  fascia,  giving  origin  to  the 
internal  oblique  and  trans\'ersalis  muscles.  Between  the  fibres  of  the  diaphragm 
which  arise  from  the  external  arcuate  ligament — over  the  quadratus  lumborum 
muscle — and  the  fibres  arising  from  the  twelfth  rib,  a  triangular  space  exists  with  its 
base  downward.  It  is  called  the  hiatus  and  if  marked  allows  the  pleura  and  the 
kidney  to  come  in  contact  without  any  muscular  fibres  intervening.  This  favors  the 
passage  of  pus  from  the  region  of  the  kidney  into  the  pleural  cavity  and  lung. 

The  anterior  surface  relations  differ  on  the  two  sides.  On  the  right  side  above 
is  the  suprarenal  gland,  then  a  large  area  where  it  is  in  contact  with  the  liver,  then 
below  to  the  inner  side  the  descending  or  second  part  of  the  duodenum,  and  below 
and  to  the  outer  side  the  hepatic  flexure  of  the  colon.  On  the  left  side  above  and 
to  the  inner  side  is  the  left  suprarenal  gland.  Beneath  it  is  a  small  area  for  the  stom- 
ach, and  still  lower  a  larger  one  for  the  left  end  of  the  pancreas.      On  the  outer 


426 


APPLIED    ANATOMY. 


lenic 


portion  of  the  anterior  surface  is  an  area  for  the  spleen  and  below  one  for  th 
fiexure  of  the  colon  and  jejunum. 

The  hilum  is  the  name  given  to  the  notch  in  the  inner  edge  of  the  kidney.  It 
contains  t\\&  pelvis  and  commencement  of  the  ureter  and  the  renal  vessels  and  nerves. 
The  si?iiis  is  the  cavity  of  the  kidney.  The  edges  of  the  pelvis  are  attached  to  the 
borders,  or  rim,  of  the  hilum. 

Renal  Vessels. — The  renal  arteries  come  off  opposite  the  first  lumbar  verte- 
bra. The  right  one,  a  little  the  longer  and  higher,  passes  out  beneath  the  vena 
cava,  head  of  the  pancreas,  and  second  portion  of  the  duodenum.  The  left  one 
passes  behind  the  pancreas.  On  reaching  the  kidney  they  break  into  three  or  four 
(sometimes  more)  branches.  One  of  these  branches  usually  proceeds  down  and 
enters  the  kidney  on  the  lower  posterior  side  of  the  pelvis.  The  other  branches 
enter  anteriorly.     The  renal  vein  on  leaving  the  kidney  is  formed  by  several  branches 


Anterior  view 


View  of  inner  edge 
Fig.  434. — The  right  kidney,  showing  the  relations  of  the  pelvis  and  blood-vessels. 


which  pass  either  in  front  or  posterior  to  the  arterial  branches.  Greig  Smith  held 
("Abdominal  Surgery,"  vol.  ii.,  p.  799)  that  the  veins  were  posterior  to  the 
arteries.  The  pelvis  is  posterior;  hence  in  searching  for  stone  if  it  is  desired  to  open 
the  pelvis  of  the  kidney  it  should  be  incised  posteriorly.  The  usually  accepted  order 
is,  pelvis  posterior,  then  the  arteries,  and  lastly  the  veins  most  anterior  (Fig.  434). 
The  blood-vessels  of  the  anterior  portion  pass  out  toward  the  cortex  and  on  passing 
its  middle  encroach  a  little  on  the  posterior  side.  For  this  reason  incisions  through 
the  kidney  substance  are  made  on  its  convex  border  about  i  cm.  (f  in.)  posterior 
to  its  middle  (Fig.  435). 

Renal  Capsules. — There  are  two  capsules  of  the  kidney — a  fibrous  one  and  a 
fatty  one.  The  fibrous  capsule  covers  the  outside  of  the  kidney  and  is  prolonged  into 
the  hilum  and  lines  the  sinus.  It  can  be  stripped  from  the  kidney,  but  when  the 
organ  is  diseased  it  brings  small  portions  of  the  kidney  substance  with  it.  T\\q  fatty 
capsule  surrounds  the  kidney,  being  more  abundant  around  its  edges  and  not  so 


THE    KIDXEYS. 


427 


much  on  its  anterior  and  posterior  surfaces.  The  kidney  hes  comparatively  loose 
in  this  fatty  capsule,  slipping  backward  and  forward.  The  fatty  capsule  is  continuous 
below  with  the  subperitoneal  fat. 

Perirenal  Fascia  of  Gerota. — Covering  the  fatty  capsule  is  the  perirenal 
fascia,  composed  of  two  layers — anterior  and  posterior.  The  anterior  is  continuous 
with  that  of  the  opposite  side  over  the  vertebral  column.  It  proceeds  outward  over 
the  vessels,  ureter,  and  kidney,  and  fatty  capsule,  blending  at  the  outer  and  upper 
border  with  the  posterior  layer  ;  below,  it  fades  away  in  the  subperitoneal  tissue  of 
the  iliac  fossa.  The  posterior  layer  passes  inward  behind  the  kidney  from  its  outer 
and  upper  borders,  to  be  attached  to  the  sides  of  the  vertebral  column.  Above,  these 
layers  are  attached  to  the  diaphragm  ;  below,  they  are  continuous  with  the  subperi- 
toneal tissue  of  the  iliac  fossa.  There  is  also  some  perirenal  fat  behind  the  perirenal 
fascia,  between  it  and  the  muscles  beneath  (Fig.  436). 

Displacement  of  the  Kidneys. — The  kidney  is  held  in  place  by  the  attach- 
ment to  the  diaphragm  of  the  perirenal  fascia,  by  its  vessels,  peritoneum,  ureter,  and 


Point  of  incision 


Posterior  surface 


Anterior  surface 


Fig.  435. — Transverse  section  of  the  kidney.      The  renal  artery  is  seen  dividing  into  anterior  and  posterior  branches. 
Incisions  into  the  organ  are  to  be  made  as  indicated  on  the  posterior  surface  just  back  of  the  prominent  edge. 

by  intra-abdominal  pressure.  Normally  it  cannot  be  felt  beneath  the  edge  of 
the  ribs.  It,  however,  readily  becomes  displaced  and  slides  down  so  as  to  be  felt 
below  the  costal  margin;  it  is  then  called  a  movable  kidney.  If  the  displacement 
becomes  more  marked  it  may  descend  into  the  iliac  fossa  or  even  toward  the  median 
line;  then  it  is  called  2i  floating  or  wanderi^ig  kidney.  In  some  instances  it  slides 
around  without  pushing  the  peritoneum  markedly  forward,  hence  it  then  has  no 
mesentery  or  pedicle.  In  other  cases  it  stretches  the  peritoneum  in  front  of  it  and 
has  sufificient  of  a  mesentery  to  allow  it  to  come  in  contact  with  the  anterior 
abdominal  wall. 

Tumors. — As  the  kidney  enlarges  it  does  so  in  a  forward  and  downward  direc- 
tion. As  it  comes  forward  it  may  go  to  the  outer  side  of  the  colon,  to  its  inner  side, 
or  carry  the  colon  directly  in  front  of  it.  Greig  Smith  ("Abdominal  Surgery," 
p.  868)  states  that  on  the  right  side  the  ascending  colon  passes  over  the  front  and  to 
the  inner  side  of  the  growth,  while  on  the  left  side  the  descending  colon  passes  to  the 
front  and  a  little  to  the  outer  side.      Renal  tumors  may  be  mistaken  for  tumors  oi 


428 


APPLIED    ANATOMY. 


the  liver  and  gall-bladder,  spleen,  and  ovaries.  A  longitudinal  coil  of  resonant  intes- 
tine passing  over  the  tumor  is  prima  facie  evidence  of  its  being  renal  in  character. 
Renal  growths  appear  as  more  or  less  spherical  tumors  which  can  in  some  cases  be 
palpated  around  their  entire  circumference.  If  one  portion  only  can  be  felt,  the 
remainder  leads  towards  the  loin  ;  in  gall-bladder  tumors  (cysts)  the  base  of  the 
growth  leads  toward  the  liver  and  is  in  contact  with  the  abdominal  wall,  overlying 
the  colon  and  small  intestine.  In  splenic  tumors  a  notch  can  sometimes  be  felt  and 
the  growth  makes  its  appearance  from  above,  down  under  the  left  costal  margin. 

Abscesses. — The  kidney  is  frequently  involved  in  suppurative  affections. 
Calculi  and  tuberculous  diseases  are  of  that  nature,  and  pyogenic  infection  may 
creep  up  from  the  bladder  producing  pyelonephritis,  or  surgical  kidney.  The  pus 
may  be  extrarenal,  involving  the  adipose  capsule  and  perirenal  fascia  ;  it  commonly 
points  in  the  loin.  As  this  fascia  is  open  below  and  to  the  inner  side  the  pus  may 
descend  to  the  iliac  fossa  or  follow  inside  the  sheath  of  the  psoas  muscle  beneath 
Poupart's  ligament.     It  may  work  its  way  up  along  the  psoas  under  the  ligamentum 


XII  rib 


Diaphragm 


Liver 

Right 

suprarenal 

body 


Iliac  fascia 


Iliacus 
muscle 


Fig.  436. — Diagrammatic  longitudinal  section,  showing  relations  of  supporting  tissue  to  right  kidney.    (Gerota.) 


arcuatum  internum  and 
hiatus  and  so  reach  the 
surface  of  the  liver  and 
into  the  duodenum  or 
lumbar  fascia  to  appear 
muscles  in  the  iliocostal 


empty  through  the  lung,  or  perforate  the  diaphragm  at  the 
lung  (page  425).  We  have  seen  it  work  along  the  under 
point  anteriorly  at  the  costal  margin.  It  may  also  rupture 
colon.  Sometimes  it  goes  posteriorly  and  perforates  the 
at  the  outer  edge  of  the  latissimus  dorsi  and  erector  spinae 
space,  or  at  the  triangle  of  Petit  (page  394). 


OPERATIONS  ON  THE  KIDNEY. 

Access  to  the  kidney  is  demanded  for  fixing  it  in  place  when  movable,  for  the 
removal  of  calculus,  for  the  treatment  of  cystic  conditions,  abscesses,  growths,  and 
even  for  the  entire  removal  of  the  organ,  which  sometimes  is  greatly  enlarged. 

Incision. — Lumbar  incisions  have  already  been  discussed  (see  page  395). 
There  are  three  things  to  be  borne  in  mind,  viz. :  the  direction  of  the  muscular  fibres 
and  position  of  the  muscles,  the  position  of  the  nerves,  and,  last,  the  pleura. 
A  longitudinal  incision  along  the  outer  edge  of  the  erector  spinae  muscle  is  large 
enough  to  remove  a  normal-sized  kidney,  but  large  kidneys  or  growths  require  an 
oblique  incision.     This  latter  begins  2  cm.  (  ^  in. )  below  the  last  rib,  at  the  edge  of 


THE    KIDNEYS.  429 

the  erector  spinae  muscle  and  passes  downward  and  forward  almost  or  quite  parallel 
to  the  twelfth  rib,  toward  the  anterior  extremity  of  the  crest  of  the  ilium.  Mayo 
Robson  (^Lancet,  May  14,  1898)  made  an  incision  from  the  inner  edge  of  the  anterior 
superior  spine  of  the  ilium  to  the  tip  of  the  last  rib.  The  fibres  of  the  external 
oblique  were  then  split  and  retracted.  Then  the  fibres  of  the  internal  oblique  and 
transversalis  were  split,  and  retracted  in  the  opposite  direction.  For  this  method  it 
is  claimed  that  no  muscles,  nerves,  or  vessels  are  divided,  and  the  patient  can  be 
operated  on  while  lying  on  the  back.  (Consult  the  Lumbar  Muscles,  page  352  ; 
Fascia,  page  393;  and  Incisions,  page  395). 

Nerves. — The  nerves  to  be  avoided  in  making  lumbar  incisions  are  the  last 
thoracic,  the  iliohypogastric,  and  the  ilio-inguinal.  The  last  thoracic  nerve,  ac- 
companied by  the  first  lumbar  artery,  runs  parallel  to  the  last  rib  a  short  distance 
below — 1.25  cm.  (5^  in.) — and  thence  pursues  a  direct  course  toward  a  midpoint 
between  the  umbilicus  and  top  of  the  pubes.  It  emerges  from  beneath  the  external 
arcuate  ligament  about  the  middle  of  the  kidney,  crossing  the  quadratus  lumborum, 
pierces  the  tendon  of  the  transversalis  muscle  and  runs  between  it  and  the  internal 
oblique  to  pierce  the  sheath  of  the  rectus  and  be  distributed  to  the  skin  midway 
between  the  umbilicus  and  top  of  pubes  and  supply  the  pyramidalis  muscle.  This 
portion  of  the  nerve  will  be  injured  only  if  the  incision  is  carried  up  to  the  twelfth 
rib.  When  it  is  about  opposite  the  tip  of  the  eleventh  rib  it  gives  off  a  lateral  (or 
iliac)  branch  which  goes  downward  and  slightly  forward  to  pierce  the  internal  and 
external  oblique  muscles  above  the  crest  of  the  ilium,  about  5  cm.  (2  in.)  posterior 
to  the  anterior  superior  spine.  This  branch  will  be  cut  in  making  the  incision, — but 
it  is  only  a  sensory  nerve,  not  a  motor. 

The  iliohypogastric  and  ilio-inguinal  nerves,  from  the  first  lumbar,  come  out 
together  from  beneath  the  psoas  muscle  opposite  the  lower  third  of  the  kidney, 
cross  the  quadratus  lumborum,  and  pass  downward  and  forward  toward  the  crest  of 
the  ilium  a  little  in  front  of  its  middle.  The  iliohypogastric  is  above  the  ilio-inguinal, 
and,  piercing  the  transversalis  muscle,  divides  into  the  hypogastric  and  iliac  branches. 
The  former  pierces  the  external  oblique  2.5  cm.  (i  in.)  above  and  a  Httle  to  the 
outer  side  of  the  external  inguinal  ring.  The  latter  goes  over  the  crest  of  the  ilium 
to  the  gluteal  region.  The  ilio-inguinal  pierces  the  transversalis  and  enters  the 
inguinal  canal  to  go  to  the  genitals  and  anterior  inner  portion  of  the  thigh. 

These  nerves  will  probably  be  seen  in  making  the  longitudinal  incision,  toward 
its  upper  portion, — they  should  be  pulled  aside.  In  the  oblique  incision  they  will  be 
posterior  and  not  visible. 

Pleura. — The  pleura  reaches  the  lower  border  of  the  posterior  portion  of  the 
twelfth  rib;  it  crosses  the  rib  posterior  to  its  middle,  if  the  rib  is  of  normal  length,  to 
pass  to  the  eleventh  rib.  Therefore,  to  avoid  the  pleura  the  incision  must  not  touch 
the  twelfth  rib  posterior  to  its  middle.  One  must  not  forget  that  the  ribs  are  irregular 
in  number  and  especially  in  length.  It  is  necessary  to  identify  the  twelfth  rib,  this 
may  be  extremely  difficult,  and  unless  the  greatest  care  is  used  a  mistake  is  liable  to 
occur.  If  the  eleventh  rib  is  mistaken  for  the  twelfth  the  pleura  comes  so  much 
farther  forward  that  it  is  almost  certain  to  be  wounded,  as  has  once  occurred,  produc- 
ing a  fatal  result.  The  ribs  may  be  counted  down  from  the  second  at  the  angle  of 
the  sternum  (Ludwig),  remembering  the  possibility  of  there  being,  as  we  have  seen, 
fourteen  ribs  on  a  side,  or  thirteen,  or  only  eleven.  The  twelfth  rib  is  frequently  so 
short  as  to  be  completely  concealed  by  the  muscles;  in  that  case  only  one  floating  rib 
would  be  seen. 

If  it  is  necessary  to  excise  a  rib,  begin  at  its  anterior  extremity,  where  it  is  not 
in  contact  with  the  pleura,  and  scrape  off  the  periosteum  from  before  backward. 

Delivering  the  Kidney. — After  getting  through  the  abdominal  wall  one 
comes  down  on  the  fat  surrounding  the  kidney  and  its  capsules.  The  kidney  is  to 
be  felt  inward  and  backward  toward  the  spine.  Having  been  located  by  touch  the 
perirenal  fascia  and  the  fatty  capsule  are  to  be  opened  and  the  kidney  pushed  and 
lifted  into  the  wound.  Do  not  go  anterior,  because  there  the  colon  or  peritoneum 
may  bulge  forward.  Once  freed  from  its  fatty  capsule  the  normal-sized  kidney  is 
sufficiently  movable  to  be  lifted  clear  out  of  the  wound  onto  the  surface.  If  it  is  too 
large  the  wound  must  be  enlarged  downward.      Incisions  into  the  kidney  substance 


430 


APPLIED    ANATOMY. 


should  be  made  only  when  the  organ  is  freely  accessible,  preferably  when  out  on  the 
surface,  and  in  the  manner  described  on  page  426.  The  frequent  existence  of  an 
additional  artery  supplying  the  lower  (or  other)  portion  of  the  kidney  should  be 
borne  in  mind.  If  it  is  desired  to  open  the  pelvis  it  should  be  sought  on  the  poste- 
rior surface,  because  the  veins  and  arteries  are  in  front  of  it. 

The  Suprarenal  Glands. — The  right  gland  is  more  on  the  upper  anterior 
surface  of  the  kidney,  while  the  left  is  more  on  the  upper  inner  surface  above  the 
hilum.  The  gland  rests  on  the  adipose  capsule  and  is  not  attached  to  the  kidney, 
so  that  when  the  fatty  capsule  is  stripped  off  in  removal  of  the  kidney  the  supra- 
renal gland  is  left  behind.  They  lie  opposite  the  eleventh  and  twelfth  dorsal  ver- 
tebrae and  are  5  to  6  cm.  (2  to  25^  in.)  apart.  A  needle  thrust  into  the  eleventh 
interspace  close  to  the  spine  would  penetrate  the  suprarenal.  The  right  one  lies 
behind  the  foramen  of  Winslow. 

Ureter,  and  Renal  Pelvis. — The  pelvis  of  the  kidney  is  the  upper  expanded 
end  of  the  ureter.  It  is  not  simply  funnel-shaped,  but  it  branches  like  a  tree.  The 
lower  portion  joining  the  ureter  is  called  the  common  pelvis,  and  this  divides  into 


upper  constriction 
Inferior  vena  cava 
Iliohypogastric  and  ilio-inguinal  nerves 

Right  common  iliac  artery 
External  cutaneous  nerve 
Genitocrural  nerve 

„- Middle  constriction 

-—External  iliac  artery 


Internal  iliac  artery 

Vas  deferens 

Opening  into  bladder,  lower 
constriction 


Fig.  437. — The  ureter,  showing  its  course  and  relations. 

the  superior  and  inferior  pelves;  these  latter  divide  into  eight  or  nine  calyces  which 
embrace  the  apices  of  the  pyramids.  The  deposition  of  salts  in  the  pelvis  causes 
the  formation  of  renal  calculi,  which  are  of  the  shape  of  the  pelvis  in  which  they 
occur.  The  arteries  and  veins  which  enter  the  kidney  do  so  on  the  anterior  surface 
of  the  pelvis;  hence  the  incision  for  the  removal  of  calculi  which  is  sometimes  made 
in  the  pelvis  itself  instead  of  through  the  kidney  substance,  is  made  posteriorly 
instead  of  anteriorly.  In  making  the  incision  care  is  to  be  taken  to  avoid  any  un- 
usual veins  or  arteries  which  may  cross  the  pelvis,  especially  at  its  lower  portion. 

In  front  of  the  pelvis  of  the  right  kidney  is  the  duodenum,  and  in  front  of  the 
left  is  the  pancreas. 

The  ureters  are  25  cm.  (10  in.)  long  when  in  the  body,  and  27.5  to  32.5 
cm.    (11    to    13    in)    long   when   removed   from    the    body    (A.    Francis   Dixon> 


THE  KIDNEYS.  431 

"Cunningham's  Anatomy").  The  left  ureter  is  a  Httle  the  longer  because  the  left 
kidney  is  the  higher.  They  are  flattened  tubes  with  a  lumen  of  3  mm.  (^  in.) 
and  possess  muscular  and  fibrous  walls.  The  contraction  of  the  marked  muscular 
walls  explains  the  intensity  of  renal  colic.  The  back-flow  of  urine  from  the  bladder 
in  diseased  conditions  may  distend  the  ureters  until  they  approach  in  size  the  small 
intestine.  Course. — The  ureter  is  in  two  parts,  an  abdominal,  extending  to  the  brim 
of  the  pelvis,  and  a  pelvic  part,  which  is  about  2. 5  cm.  ( i  in. )  longer  than  the 
abdominal.  The  abdominal  portion  extends  from  4  cm.  ( i  ^  in. )  to  the  outside  of 
the  median  line  opposite  the  second  lumbar  vertebra  to  3  cm.  ( i  ^  in. )  outside  of  the 
median  line  on  a  line  joining  the  anterior  superior  spines  of  the  ilia.  It  descends 
on  the  psoas  muscle  almost  parallel  to  the  median  line  but  inclining  a  little  inward 
and  crosses  the  brim  of  the  pelvis  at  the  bifurcation  of  the  common  iliac  artery  (the 
right  being  sometimes  a  little  lower).  It  will  be  observed  that  at  this  point  the 
right  ureter  lies  immediately  to  the  inner  side  of  the  base  of  the  appendix.  There 
are  three  narrowed  parts;  the  first  or  superior  isthmus  is  7  cm.  (2^  in.)  below  the 
hilum,  where  the  ureter  turns  forward  on  the  psoas  muscle;  the  second  or  inferior 
isthmus  is  at  the  pelvic  brim;  and  the  third  is  where  it  enters  the  bladder.  Calculi 
may  lodge  at  any  of  these  points.  If  this  occurs  at  the  brim  in  the  right  ureter  the 
case  may  be  mistaken  for  one  of  appendicitis,  for  the  location  of  the  two  affections 
would  be  almost  identical.  The  abdominal  ureter  does  not  possess  as  distinct  a 
sheath  as  does  the  pelvic  ureter.  It  is  stuck,  however,  by  fibrous  tissue  to  the  peri- 
toneum, so  that  when  the  latter  is  raised  it  comes  up  with  it.  The  ureters  are 
crossed  about  their  middle  and  accompanied  by  the  spermatic  or  ovarian  vessels. 
Just  below  the  middle  of  the  abdominal  portion  of  the  ureters  the  genitocrural  nerve 
emerges  from  the  psoas  muscle  and  passes  beneath  the  ureters  from  within  out. 
This  explains  the  genital  pain  in  cases  of  calculi. 

Operations. — The  abdominal  portion  of  the  ureter  can  be  reached  for  operative 
purposes  by  prolonging  the  oblique  incision  used  in  kidney  procedures  downward. 
It  should  pass  about  2. 5  cm.  ( i  in.  )  in  front  of  the  anterior  spine  and  the  same  distance 
above  Poupart's  ligament.  To  find  the  ureter,  Frederick  C.  Herrick  advises  carrying 
the  finger  to  the  bifurcation  of  the  common  iliac  artery  and  then  turning  it  up  against 
the  under  surface  of  the  peritoneum  where,  closely  adherent  to  the  peritoneum  and 
covered  by  some  of  its  reflected  fibres,  will  be  found  the  ureter.  After  cutting 
these  fibres,  traction  on  the  ureter  will  cause  it  to  stand  out  as  a  ridge  extending  to 
the  base  of  the  bladder.  Access  to  the  ureter  through  the  abdominal  cavity  is  not 
satisfactory  because  of  the  presence  of  the  duodenum  and,  when  distended,  the 
ascending  colon  on  the  right  side  and  the  sigmoid  and  distended  descending  colon 
on  the  left.  The  surest  way  of  recognizing  the  ureter  in  operations  is  to  follow  it 
downward  from  the  hilum  of  the  kidney  or  to  have  it  contain  an  ureteral  catheter 
introduced  upward  into  it  from  the  bladder. 

The  ureter  (with  the  kidney)  is  most  often  excised  for  tuberculous  disease;  there- 
fore, instead  of  its  ha\ing  its  normal  size  of  5  mm.  (i  in. )  when  distended,  its  diam- 
eter may  be  increased  to  12  mm.  or  18  mm.  {yi  to  %  in.).  Excision  has  been 
most  often  done  in  women,  as  in  them  the  pelvic  portion  is  much  more  accessible. 
It  can  be  reached  through  an  incision  in  the  anterior  vaginal  wall  at  its  upper  portion 
instead  of  using  an  oblique  incision  through  the  abdominal  muscles.  Konig  advised 
a  transverse  incision  between  the  lower  edge  of  the  ribs  and  the  crest  of  the  ilium. 
Bovee  {Journal  of  Am.  Med.  Assoc.,  Oct.  23,  1909)  gives  the  following  technic: 
The  cervix  uteri  is  to  be  drawn  downward  with  a  volselluin.  On  the  anterior  vaginal 
wall,  at  the  uterovesical  juncture,  a  small  dimple  will  be  seen.  From  the  outer  side 
of  this  dimple  an  incision  from  one  to  one  and  a  half  inches  in  length  is  made  down- 
ward and  outward.  By  careful  blunt  dissection  the  ureter  can  be  exposed,  brought 
down  with  a  hook,  and  traction  made  to  liberate  it  as  it  passes  through  the  broad 
ligament.  Its  lower  end  may  then  be  ligated  and  divided.  At  this  stage  of  the 
operation  the  pelvic  portion  of  the  ureter  may  be  resected  or  not  as  desired.  Then 
a  transverse  incision,  four  inches  or  longer,  is  made  through  the  extraperitoneal 
portion  of  the  abdominal  wall,  opposite  the  lower  pole  of  the  kidney  (Konig);  its 
inner  end  need  not  go  beyond  the  semilunar  line.  Through  this  wound  the  kidney 
is  liberated  and  brought  out  and  the  ureter  separated  by  gentle  traction  and  freeing 
with  the  fingers. 


43- 


APPLIED   ANATOMY. 


THE  PELVIS. 

The  pelvis  is  composed  of  the  two  innominate  bones,  the  sacrum,  and  the  coccyx. 
It  is  constructed  with  a  view  to  connecting  the  lower  extremities  with  the  trunk,  to 
support  the  weight  of  the  trunk  and  to  promote  locomotion,  to  act  as  a  receptacle 
and  protector  of  the  pelvic  viscera  and  to  fulfil  the  function  of  parturition. 

In  infancy  locomotion  and  parturition  are  in  abeyance,  hence  the  pelvis  is  un- 


Quadratus  lumborum 


Erector  spinae 

Latissimus  dorsi 


Transversalis 

Obliquus  intemus 
Obliquus  extemus 

Iliacus 

Anterior  superior  spine 
Sartorius 
Anterior  inferior  spine 
Rectus  femoris 

Pyriformus 

Acetabulum 

Iliopectineal  line 

Pectineus 

Obturator  externus' 
Adductor  magnus 


-  Levator  am 
Pyramidalis 
Crest  of  pubis 

Rectus  abdominis 
Spine  of  pubis 
Adductor  longus 
Adductor  brevis 
Gracilis 


Fig.  438. — The  male  pelvis,  front  view. 


developed,  the  bladder  and  uterus  are  almost  entirely  in  the  abdomen,  and  the 
rectum  is  almost  straight.  As  the  child  begins  to  use  its  lower  limbs  for  locomotion 
the  pelvis  increases  progressively  with  the  growth  of  the  lower  extremities,  and  with 
the  advent  of  puberty  its  development  is  completed.     The  structure  of  the  pelvis  in 


Quadratus  lumborum         Latissimus  dorsi 


Gluteus  medius' 
Gluteus  maximus , 

Gluteus  minimus 
Tensor  fascia  femoris 


Erector  spinse 
Reflected  tendon  of  rectus 

Gluteus  maximus 

Gemelli 
Semi  membranosus 

Biceps  and  semitendinosus 

Obturator  internus 


Posterior  superior  spine 


terior  inferior  spine 


Spine  cf  ischium 


Tuberosity  of  ischium 


Levator  ani 
Fig.  439- — The  male  pelvis,  back  view. 

relation  to  the  function  of  locomotion  will  be  considered  later  in  connection  with  the 
pelvic  girdle  and  lower  extremity;  here  we  will  consider  it  in  relation  to  the  pelvic 
viscera  and  their  functions. 

That  part  of  the  pelvis  above  the  iliopectineal  line  has  been  called  the  false 
pelvis,  while  that  below  is  the  true  pelvis.  The  inlet  of  the  pelvis  is  formed  anteriorly 
by  the  crest  and  spine  of  the  pubes,  the  iliopectineal  lines  on  the  sides,  and  the  base 


THE  PELVIS. 


433 


of  the  sacrum  with  its  promontory  posteriorly.  The  outlet  is  formed  by  the  pubic 
arch  anteriorly  with  the  symphysis  in  the  middle,  the  rami  of  the  pubes  and  ischia 
on  the  sides,  and  the  great  sacrosciatic  ligaments  and  coccyx  posteriorly.  The  vis- 
cera above  the  inlet  are  abdominal,  those  below  are  pelvic.  When  the  body  is  ver- 
tical the  inlet  forms  an  angle  of  60  degrees  with  the  horizon,  and  the  promontory 
of  the  sacrum  is  9  to  10  cm.  (3^  to  4  in.)  above  the  upper  edge  of  the  symphysis. 

The  male  pelvis  is  fashioned  preeminently  for  locomotion  :  it  is  both  heavier 
and  rougher ;  the  false  pelvis  is  broad  and  shallow,  while  the  true  pelvis  is  deep  and 
narrow  and  its  capacity  is  less.  The  inlet 
is  heart-shaped,  the  tuberosities  closer  to- 
gether, and  the  pubic  arch  narrower.  The 
obturator  foramen  is  oval  (see  Figs.  438 
and  439). 

The  Female  Pelvis. — In  addition 
to  the  functions  common  to  the  two  sexes 
the  female  has  that  of  child-bearing.  To 
fulfil  this  the  female  pelvis  is  different  from 
that  of  the  male.  It  is  smoother,  its  bony 
prominences  not  being  so  marked  (see  Fig. 
440).  The  extreme  width  of  the  pelvis 
does  not  differ  much  in  the  two  sexes,  some 
authorities  giving  them  as  of  equal  size  and 
some  stating  that  the  female  is  slightly  nar- 
rower. Its  cavity  is  larger  and  shallower. 
The  symphysis  pubis  is  narrower  and  the 
sacrum  is  shorter  and  less  curved.  The 
acetabula  are  set  wider  apart  as  are  also  the 
tuberosities.  This  causes  the  thyroid  fora- 
men to  be  triangular  in  the  female  while  it 
has  a  long  diameter  parallel  with  the  long 
axis  of  the  body  in  the  male.  It  also  causes 
the  subpubic  angle  to  be  greater  in  the 
female,  forming  an  angle  of  about  90  de- 
grees as  against  65  degrees  to  70  degrees  in 
the  male.  The  inlet  of  the  female  pelvis  is 
more  oval  and  not  so  heart-shaped.      The 

cavity  is  largest  at  a  level  between  the  second  and  third  sacral  vertebrae  posteriorly 
and  the  middle  of  the  symphysis  anteriorly.  It  is  smallest  between  the  sacrococcygeal 
articulation  behind  and  the  lower  third  of  the  symphysis  in  front,  and  the  spines  of 
the  ischia  on  the  sides.     There  are  three  diameters  of  the  pelvis  used  in  obstetrics. 

Dwight,  in  "Piersol's  Anatomy,"  gives  them  as  follows  : 


Superior  view,  inlet. 


Inferior  view,  outlet. 


Fig.  440. — The  female  pelvis,  superior  and  inferior 
views,  with  the  diameters  of  the  inlet  and  outlet. 


' 

Inlet, 
cm.     (in.) 

Male. 

Cavity, 
cm.    (in.) 

Outlet, 
cm.    (in.) 

Inlet, 
cm.     (in.) 

Female. 

Cavity, 
cm.       (in.) 

Outlet, 
cm.    (in.) 

Anteroposterior 
Transverse    .    . 
Oblique     .    .    . 

10.25  (4) 
12.75(5) 

ii-5(4>^) 
120(4^) 

II-5  {A'A) 

8.25  (3X) 
9-00  (3>4) 
10.25  (4) 

10.25(4) 
13-25  (5J<) 
12.75(5) 

12.75  (5) 
12.75  (5) 
13-25  (5X) 

11.5(4^) 
12.0(4^) 

11-5  (4>^) 

Sacro-iliac  Articulation. — The  sacrum  is  wider  in  front  than  behind  and 
larger  above  than  below.  This  causes  it  to  be  wedged  between  the  two  ilia  where  it 
is  firmly  held  by  the  sacro-iliac  ligaments,  the  irregularity  of  the  joint  surfaces  and 
the  thinness  of  the  cartilaginous  layer.  A  small  amount  of  movement  is  possible  in 
most  cases  :  it  takes  place  around  a  transverse  axis  about  opposite  to  the  second  sacral 
foramina.  If  relaxation  of  the  ligaments  occurs  through  pregnancy,  osteo-arthritis 
or  the  stress  of  strains  due  to  occupation,  etc. ,  symptoms  of  looseness  and  discomfort 
appear  which  demand  relief.  Flexion  produces  pain.  Treatment  consists  in  fixing 
the  joints  by  firm  belts  around  the  pelvis  or  applying  a  low  plaster  of  Paris  jacket  or 
spinal  corset  or  brace  which  both  compresses  the  pelvis  and  fixes  the  lumbar  spine 
and  prevents  movements  in  both  antero-posterior  and  lateral  directions. 
28 


434 


APPLIED    ANATOMY. 


The  cavity  of  the  pelvis  is  narrowed  somewhat  by  the  soft  parts  on  its  sides. 
The  blood-vessels,  nerves,  and  obturator  muscles  are  placed  laterally  and  so  usually 
escape  injury.  In  pregnancy  the  venous  flow  is  most  often  interfered  with.  The 
first  evidence  of  this  is  the  dusky  hue  of  the  vagina;  hemorrhoids  and  varicosities  of 
the  veins  of  the  external  genitals  and  lower  extremities  are  common.  The  rectum 
and  bladder  being  placed  more  anteroposteriorly,  interference  with  their  functions  is 
frequent.  The  peculiarities  of  the  female  pelvis  are  evident  from  birth  and  are  not 
solely  acquired  with  age. 

Pelvic  \A^alls. — On  looking  laterally  at  the  inside  of  the  pelvis,  the  iliopecti- 
neal  line  is  seen  separating  the  abdominal  from  the  pelvic  portion.  On  the  iliac  or 
abdominal  portion  lie  the  iliacus  and  psoas  muscles.  Below  the  iliopectineal  line 
anteriorly  is  the  body  of  the  pubis  with  the  symphysis  in  the  median  line.  The 
descending  ramus  of  the  pubis  passes  down  to  be  continuous  with  the  ramus  of  the 
ischium  to  the  tuberosity.  A  short  distance  above  the  tuberosity  is  the  spine  of  the 
ischium.  Posteriorly  are  the  five  vertebrae  of  the  sacrum  and  the  four  of  the  coccyx. 
Passing  upward  from  the  tuberosity  of  the  ischium  to  the  sacrum  is  the  great  sacro- 
sciatic  ligaine7it  (ligamenhmi  sacrotuberosuni) ;  passing  backward  from  the  spine  of 
the  ischium  to  the  sacrum  and  coccyx  is  the  lesser  sacrosciatic  ligament  (ligameyitiim 
sacrospinosum) .    The  large  opening  above  the  lesser  sacrosciatic  ligament  is  \k\Q.  great 


Iliac  fossa  and  iliac  muscle 
Tensor  fasciae  femoris 
Anterior  superior  spine 
and  sartorius  muscle 

Anterior  inferior  spine 
and  rectus  femoris  muscle 

Iliopectineal  line 


Spine  of  pubis 
Crest  of  pubis 
Symphysis 
Levator  ani  muscle 

Transverse  perineal  muscle 
Obturator  intemus 


Coccygeus 

Fig.  441. — View  of  the  pelvis  from  the  inside 


sacrosciatic  foramen.  Through  it  pass  the  pyriformis  muscle,  with  the  gluteal  vessels 
and  superior  gluteal  nerve  above,  and,  below,  the  sciatic  vessels  and  nerves,  tlie 
internal  pudic  vessels  and  nerve,  the  inferior  gluteal  nerve,  and  the  nerves  to  the 
obturator  internus  and  quadratus  femoris.  The  smaller  opening  below  the  lesser 
sacrosciatic  ligament  is  the  lesser  sacrosciatic  foramen,  through  which  passes  the 
tendon  of  the  obturator  internus,  the  nerve  to  it,  and  the  internal  pudic  vessels  and 
nerve.  In  front  of  these  two  foramina  is  a  third,  the  obturator.  It  is  closed  by  a 
membrane  except  at  its  upper  inner  portion,  which  gives  exit  to  the  obturator  vessels 
and  nerve.  Attached  to  the  inner  surface  of  this  membrane  is  the  origin  of  the 
obturator  internus  muscle  and  to  its  outer  surface  the  obturator  externus  (Fig.  441). 
Pelvic  Floor. — The  pelvic  outlet  is  closed  by  two  muscles,  the  levator  ani  and 
coccygeus.  These  on  each  side  constitute  the  pelvic  floor.  The  coccygeus  is 
a  comparatively  small  muscle  passing  from  the  spine  of  the  ischium  to  the  coccyx. 
The  levator  ani  is  the  main  muscle  which  supports  and  retains  the  pelvic  and 
abdominal  viscera  in  their  normal  positions.  It  arises  from  the  "  white  line"^ — which 
is  a  thickening  of  the  pelvic  fascia  extending  from  the  posterior  surface  of  the  pubes 
in  front  to  the  spine  of  the  ischium  behind — and  descends  to  be  attached  to  the 
coccyx  posteriorly,  then  around  the  lower  portion  of  the  rectum  just  above  the  exter- 
nal sphincter  and,  farther  front,  surrounds  the  vagina  of  the  female  or  the  prostate 
gland  in  the  male.      The  part  surrounding  the  prostate  has  been  called  the  levator 


THE  PELVIS. 


435 


prostata.  The  anterior  edge  of  the  IcA-ator  ani  muscle  reaches  to  the  central  tendon 
of  the  perineum  (Fig.  442). 

Pelvic  Herniae. — Hernial  protrusions  of  the  pelvic  contents  may  occur  through 
the  upper  portion  of  the  obturator  membrane,  following  the  vessels  and  nerve.  This 
is  called  an  obtjirator  hernia.  The  sac  is  usually  to  the  medial  or  inner  side  of  the 
vessels  and  nerve.  It  makes  its  appearance  in  Scarpa's  triangle  and  is  covered  by 
the  pectineus  muscle.  Death  has  frequently  occurred  in  these  cases  from  strangula- 
tion. Sciatic  hernia  is  the  name  given  to  those  forms  in  which  the  intestine  escapes 
through  the  great  sciatic  notch,  passing  just  above  or  just  below  the  pyriformis 
muscle.  Perineal  hernics  are  those  which  work  their  way  downward  in  other  places. 
Thus  the  sac  may  push  down  between  the  rectum  and  bladder  and  bulge  in  the 
perineum.  It  may  pass  between  the  coccygeus  and  levator  ani  muscles  or  between 
the  fibres  of  the  latter  and  bulge  into  the  ischiorectal  fossa  or  forward  into  the  labium 
of  the  female. 

Prolapse. — The  rectum  and  vagina  as  they  pierce  the  pelvic  floor  may  pro- 
lapse or  protrude  through  the  anus  or  vulva.      Prolapse  of  the  rectum  is  a  common 


Pvriformis 


Coccygeus  muscle 


Spine  of  ischium 

Cut  edge  of  levator  ani  in 
middle  line 


Levator  ani  muscle 


Iliopectineal  line 
Obturator  intemus 
Obturator  foramen 

White  line 

Bladder 
Uterus 


Fig.  442. — Levator  ani  muscle  and  interior  of  pelvis;    the  bladder,  uterus  and  vagina,  and  rectum  have  been 

loosened  and  turned  down. 

affection  and  if  marked  may  drag  down  the  peritoneum  so  that  some  coils  of  small 
intestine  may  be  around  the  prolapsed  part.  In  childbirth  the  pelvic  outlet  is  fre- 
quently torn  and  the  vagina  prolapses  and  may  drag  the  uterus  down  with  it,  or,  the 
support  being  lost,  the  uterus  descends  and  drags  the  vagina  with  it  and  everts  it. 
The  vaginal  outlet,  if  much  rela.xed,  allows  the  rectum  to  bulge  downward  and  for- 
ward, forming  a  rectocele,  or  the  bladder  may  bulge  downward  and  backward,  forming 
a  cystocele  (see  Fig.  466,  page  463). 

The  Pelvic  Fasciae. — As  the  iliac  fascia  passes  over  the  brim  of  the  pelvis  it 
covers  the  internal  obturator  muscle  on  the  walls  of  the  pelvis,  hence  it  is  called 
the  obturator  fascia.  From  the  upper  posterior  surface  of  the  arch  of  the  pubes 
anteriorly  to  the  spine  of  the  ischium  posteriorly  this  obturator  fascia  is  thickened, 
forming  the  ''  white  line''  to  give  origin  to  the  levator  ani  muscle.  At  the  white 
line  the  obturator  fascia  gives  ofl  a  visceral  layer — the  rectovesical  fascia — which 
covers  the  inner  or  upper  surface  of  the  levator  ani,  then  a  second  layer,  the  anal 
fascia,  covering  the  under  or  outer  surface  of  the  levator  ani  muscle,  while  the 
obturator  fascia  itself  is  continued  down  on  the  obturator  internus  muscle  to  form 


APPLIED    ANATOMY. 

the  outer  wall  of  the  ischiorectal  space.  The  rectovesical  fascia  passes  downward 
and  inward  over  the  levator  ani  muscle  to  cover  the  pyriformis  and  coccygeus 
muscles  behind,  then  the  rectum,  vagina,  and  bladder  in  front.  In  the  male  it 
covers  the  prostate  gland,  forming  its  sheath,  and  at  its  anterior  portion  forms  the 
deep  or  posterior  layer  of  the  triangular  ligament  of  the  perineum.  This  pelvic 
fascia  acts  as  a  barrier  between  the  abdominal  and  pelvic  cavities  above  and  the 
perineal  region  below.  Pus  originating  above  it  tends  to  form  an  abscess  which 
rises  toward  the  abdominal  cavity,  and  pus  originating  below  it  tends  to  work  toward 
the  surface  in  the  perineum. 

Iliac  Vessels. — The  iliac  arteries  commence  at  the  bifurcation  of  the  aorta  on 
the  left  side  of  the  disk  between  the  third  and  fourth  lumbar  vertebrae.  This  is  2  cm. 
(^  in. )  below  and  to  the  left  of  the  umbilicus  and  on  a  level  with  a  line  joining  the 
highest  points  of  the  iliac  crests.  They  run  in  a  line  drawn  from  this  point  to  mid- 
way between  the  anterior  superior  spine  of  the  ilium  and  the  symphysis  pubis.  This 
is  to  the  inner  side  of  the  middle  of  Poupart's  ligament.  They  are  about  15  cm. 
(6  in.)  in  length,  the  upper  third,  5  cm.  (2  in.),  being  the  common  iliac  and  the 
lower  two-thirds,    10  cm.  (4  in.),   being  the  external  iliac  arteries.     The  internal 


^^H^F~. 


Aponeurosis  of  the  external  oblique 

Internal  oblique  and 
transversalis  muscles 

—  External  iliac  artery 
External  iliac  vein 
Deep  epigastric  artery 
Deep  epigastric  vein 


Fig.  443. — Ligation  of  the  external  iliac  artery. 

iliac  comes  off  opposite  the  sacro-iliac  joint  on  or  a  little  above  a  line  joining  the 
anterior  superior  spines.  The  right  common  iliac  artery  is  a  litde  the  longer  because 
it  comes  from  the  left  side  of  the  vertebral  column,  and  the  left  common  iliac  vein  is 
the  longer  because  it  goes  to  the  right  side.  The  left  iliac  veins  lie  to  the  inner  side 
of  the  left  iliac  arteries  in  their  entire  course.  The  tight  iliac  vein  starts  at  the 
inner  side  of  the  right  external  iliac  artery  and  then  passes  behind  it  to  reach  the 
vena  cava  on  the  right  side  of  the  vertebral  column.  The  ureters  cross  the  iliac 
arteries  at  their  bifurcation,  and  in  the  female  are  accompanied  by  the  ovarian  arteries 
and  veins.  The  genitocrural  nerve  passes  downward  on  the  external  iliac  artery  and 
goes  with  it  beneath  Poupart's  ligament.  Lymphatic  nodes  accompany  the  iliac 
vessels  and  drain  the  lower  extremity,  the  abdomen  below  the  umbilicus  and  the 
pelvic  viscera. 

Ligation  of  the  Iliac  Arteries. — The  iliac  arteries  can  be  reached  for  liga- 
tion through  an  incision  2  cm.  above  and  parallel  to  Poupart's  ligament,  reaching 
from  the  inner  side  of  the  external  iliac  artery  to  above  the  anterior  superior  spine 
if  necessary.  If  the  external  iliac  only  is  to  be  ligated  this  can  be  done  through  a 
comparatively  small  incision,  but  if  it  is  desired  to  reach  the  internal  or  common  iliac 
then  the  incision  must  be  quite  large.  When  the  peritoneum  is  reached  it  is  lifted 
up  from  the  iliac  fascia  beneath  and  the  external  iliac  artery  followed  up  as  far  as 
desired.  When  the  peritoneum  is  raised  the  ureter  is  usually  lifted  with  it;  it  will 
be  encountered  crossing  the  point  of  bifurcation  of  the  common  iliac  into  the  external 
and  internal  iliacs.  The  relation  of  the  veins  to  the  iliac  artery  on  the  two  sides  is 
to  be  borne  in  mind  when  passing  the  needle  (Fig.  443). 


THE  PELVIS.  437 

Collateral  Ciradation  (Fig.  444). — When  the  external  ihac  artery  is  hgated  tha 
following  anastomoses  occur  : 

Iliolumbar with  deep  circumflex  iliac 

Gluteal with  external  circumflex 

Obturator with  internal  circumflex 

Sciatic with  superior  perforating 

Internal  pudic with  deep  external  pudic 

Internal  mammary,  intercostals,  and  lumbars   .    .  with  deep  epigastric 


Iliolumbar  artery 


Gluteal  artery 


Deep  circumflex 
iliac  artery 


Common  femoral  artery 


Profunda  artery 


External  circum- 
flex artery 


Aorta 


Common  iliac  artery 

Middle  sacral  artery 

\ External  iliac  artery 

Internal  iliac  artery 
-  Deep  epigastric  artery 

Sciatic  artery 
Obturator  artery 


Internal  pudic  artery 

Deep  external 
pudic  artery 

Internal  circum- 
flex artery 


Superior,  middle,  and  in- 
ferior perforating  arteries 


Fig.  444. — Collateral  circulation  after  ligation  of  the  external  iliac  artery, 


Ligation  of  the  iliac  arteries  by  a  transperitoneal  instead  of  subperitoneal  route 
has  been  advocated  by  Dennis  {Medical  News,  Phila. ,  1886).  This  lessens  the 
danger  of  wounding  the  deep  circumflex  iliac  and  deep  epigastric  arteries,  the  vas 
deferens,  the  ureter,  puncturing  the  veins  and  loosening  up  the  subperitoneal  tissue. 
Treves  has  used  a  median  incision  from  the  umbilicus  to  the  pubes. 


438 


APPLIED    ANATOMY. 


THE  PELVIC  VISCERA. 
RECTUM  AND  ANAL  CANAL. 

The  rectum  extends  from  the  level  of  the  third  sacral  vertebra  to  where  it 
pierces  the  levator  ani  muscle,  3. 7  cm.  ( i  %  in. )  in  front  of  the  tip  of  the  coccyx, 
but  at  a  lower  level,  and  opposite  the  lower  and  anterior  part  of  the  prostate.  It  is 
8.75  cm.  (t,}4  in.)  long  and  passes  into  the  anal  canal  ;  this  latter  is  2.5  to  4  cm. 
(i  to  i}4  in.)  long,  and  extends  to  the  skin  border  (Fig.  445). 

When  collapsed  the  rectum  appears  as  a  nearly  straight  tube  following  the  curve 
of  the  sacrum,  but  when  distended  it  becomes  distincdy  sacculated  It  possesses  an 
external  longitudinal  and  internal  circular  layer  of  muscular  fibres.  The  longitudinal 
fibres  are  continuous  with  those  on  the  colon  but  instead  of  being  composed  of  three 


Rectovesical  pouch 

Seminal  vesicles 

Prostate  gland 
Recto-urethralis  muscle 


Valves  of  Houston 


Ampulla 

Columns  of  Morgagni 
Internal  sphincter 

External  sphincter 


Crypts  of  Morgagni 


\  Compressor  urethra?  muscle 
with  Cowper's  gland  enclosed 


Fig.  445. — Rectum  and  anal  canal. 


bands  are  fused  together  into  two  bands,  anterior  and  posterior.  On  the  sides  the 
longitudinal  fibres  are  not  so  abundant.  The  circular  fibres  are  continuous  on  the 
anal  canal  as  the  internal  sphincter.  For  the  distance  of  4  cm.  ( i  }4  in. )  between 
the  tip  of  the  coccyx  and  its  termination,  the  rectum  lies  on  the  two  levator  ani 
muscles,  which  join  in  the  median  line.  The  lower  portion  of  the  rectum  is  larger 
than  the  upper  and  is  called  the  ampulla. 

The  anterior  surface  of  the  rectum  at  the  ampulla  lies  against  the  posterior  sur- 
face of  the  prostate  but  is  not  intimately  adherent  to  it.  At  the  apex  of  the  prostate 
the  anterior  rectal  wall  makes  a  more  or  less  sharp  turn  backward.  At  this  part  the 
rectum  and  the  prostate  are  embraced  by  the  fibres  of  the  levator  ani  muscle,  which 
practically  blend  with  the  compressor  urethrae  muscle  and  surround  the  membranous 
urethra.  The  muscular  fibres  passing  from  the  longitudinal  layer  of  the  rectum  to  the 
membranous  urethra  have  been  called  by  Proust  the  recto-urethi-alis  muscle ;  they 


RECTUM    AND    ANAL    CANAL.  439 

keep  the  lower  extremity  of  the  ampulla  of  the  rectum  in  close  approximation  to 
the  apex  of  the  prostate.  This  is  the  part  of  the  rectum  which  has  been  frequently 
wounded  in  the  operations  of  perineal  lithotomy  and  prostatectomy.  In  the  latter 
operation  division  of  this  band  allows  the  rectum  to  be  pushed  back  and  exposes  the 
apex  of  the  prostate. 

The  sacculation  of  the  rectum  is  produced  by  three  creases  or  crescentic  folds, 
called  the  rectal  valves  or  valves  of  Houston  (^Dublin  Hospital  Reports,  1830).  Of 
these  the  middle  is  the  largest.  It  springs  from  the  right  anterior  quadrant  about 
5  to  6  cm.  (2  to  2)4,  in.)  above  the  margin  of  the  anal  canal.  The  superior  and 
inferior  valves  spring  from  the  left  posterior  quadrant  a  short  distance  above  and 
below  the  middle  valve.  At  the  juncture  of  the  rectum  and  sigmoid  flexure  there  is 
another  fold  on  the  anterior  wall  which  tends  to  obstruct  the  view  in  making  ex- 
aminations. These  valves  are  composed  of  connective  tissue  and  circular  muscular 
fibres  covered  with  mucous  membrane. 

Peritoneal  Relations. — The  posterior  portion  of  the  rectum  has  no  peritoneal 
covering,  the  mesosigmoid  ceasing  opposite  the  third  sacral  vertebra,  about  12.50 
cm.  (5  in.)  from  the  anus.  From  this  point  the  peritoneum  slopes  downward  and 
forward,  covering  the  sides  and  anterior  surface  of  the  rectum  5  cm.  (2  in.)  lower. 
The  peritoneum  is  here  reflected  forward  over  the  bladder  in  the  male  forming  the 
rectovesical  pouch  and  over  the  vagina  and  uterus  in  the  female  forming  the  pouch 
of  Douglas.  It  is  within  7.5  to  8.5  cm.  (3  to  3^  in.)  of  the  anus.  This  leaves  2.5 
cm.  ( I  in. )  or  more  above  the  prostate  which  is  not  covered  by  peritoneum.  It  was 
through  this  space  that  the  bladder  was  formerly  tapped  with  a  trocar  to  relieve  it 
when  distended.  The  peritoneum  on  the  sides  is  less  firmly  attached  to  the  rectum 
and  pelvic  colon  than  it  is  on  its  anterior  surface. 

Rectal  Examination. — The  finger  can  palpate  the  anal  canal  and  rectum  for 
a  distance  of  10  cm.  (4  in.)  from  the  surface.  Anteriorly  as  soon  as  the  finger 
passes  the  sphincters  the  apex  of  the  prostate  can  be  felt  ;  also  the  membranous 
urethra,  particularly  if  it  contains  a  bougie  or  sound.  The  prostate  can  be  outlined 
and  its  size  determined.  If  the  prostate  is  not  enlarged  the  base  of  the  bladder 
above  can  be  palpated  and  the  tip  of  the  finger  will  reach  the  rectovesical  pouch. 
From  the  upper  or  posterior  edge  of  the  prostate  and  extending  from  near  the  mid- 
line upward  and  outward  are  the  seminal  vesicles,  sometimes  the  seat  of  tuberculous 
disease.  Just  to  the  outer  side  of  the  upper  end  of  the  seminal  vesicles  are  the 
lower  ends  of  the  ureters.  Should  a  ureteral  calculus  become  impacted  at  this 
point  it  might  possibly  be  felt  through  the  rectum.  Posteriorly  the  coccyx  and  the 
hollow  of  the  sacrum  can  be  felt.  The  segments  of  the  coccyx  frequently  are 
luxated  or  fractured  and  it  is  the  seat  of  pain — coccygodynia — for  which  excision  is 
done.  These  injuries  cause  either  an  ankylosis  or  a  deformity  of  the  coccyx  which 
can  often  readily  be  detected  by  a  finger  internally  and  the  thumb  externally.  Later- 
ally the  finger  can  explore  the  region  of  the  spine  of  the  ischium,  the  sacrosciatic 
foramina,  and  the  tuberosities.  If  a  patient  is  placed  in  the  knee-chest  position  and 
a  speculum  is  introduced  the  rectum  immediately  distends  with  air,  and  its  interior  is 
visible  as  far  as  the  promontory  of  the  sacrum.  By  means  of  extra  long  tubes  even 
the  sigmoid  loop  can  sometimes  be  seen.  The  valves  of  Houston  are  readily  seen 
through    the  speculum. 

In  introducing  tubes  and  bougies  for  examination  or  therapeutic  purposes  the 
greatest  care  is  necessary,  as  death  has  not  infrequently  resulted  from  perforation  into 
the  peritoneal  cavity. 

The  Anal  Canal. — This  extends  from  the  rectum  to  the  anus  or  its  opening 
on  the  skin,  a  distance  of  2.5  to  4  cm.  (i  to  i^  in.  j.  It  begins  at  the  level  of  the 
levator  ani  muscles  and  has  the  apex  of  the  prostate  directly  in  front  of  it  and  the  tip 
of  the  coccyx  behind  and  a  little  above.  With  the  body  vertical  the  anal  canal  has 
its  axis  inclining  upward  and  forward  toward  the  bladder;  as  soon  as  the  sphincter  ani 
is  passed  the  axis  of  the  rectum  changes  to  upward  and  backward  toward  the  hollow 
of  the  sacrum.  In  intruducing  a  speculum  it  should  always  be  inclined  first  ante- 
riorly and  then  posteriorly.  Opposite  the  level  of  the  levator  ani  the  circular  mus- 
cular fibres  increase  to  form  the  interyial  sphincter.  This  extends  down  the  anal 
canai  for  a  distance  of  approximately  2. 5  cm.  ( i  in. )  and  ends  above  the  skin  margin 


440 


APPLIED    ANATOMY. 


or,  as  it  has  been  called,  the  "white  line  of  Hilton."  The  external  sphincter  sur- 
rounds the  lower  part  of  the  canal  and  stretches  in  a  spindle  shape  from  the  tip  of  the 
coccyx  to  the  central  point  or  tendon  of  the  perineum.  Anteriorly  it  blends  with  the 
fibres  of  the  levator  ani  and  the  other  muscles  of  the  perineum.  It  is  a  thick,  power- 
ful, voluntary  muscle  and  extends  outward  from  the  white  line  of  Hilton  or  muco- 
cutaneous junction. 

Mucous  Membrane. — The  upper  half  of  the  mucous  membrane  of  the  anal  canal 
has  six  or  eight  longitudinal  ridges  or  folds  called  the  cohinvis  of  Morgagni  or  Glis- 
son.  Between  the  lower  ends  of  these  columns  are  small  hollows  called  the  crypts  of 
Morgagni,  and  the  free  edges  of  the  mucous  membrane  guarding  the  crypts  are  the 
anal  valves. 

BLOOD-VESSELS. 

Arteries. — The  rectum  and  anal  canal  are  supplied  by  the  superior,  middle,  and 
inferior  hemorrhoidal,  and  middle  sacral  arteries  (Fig.  446). 

The  siipet  ior  hemorrhoidal  artery  is  the  terminal  branch  of  the  inferior  mesen- 


Inferior  mesenteric  artery 


Superior  hemorrhoidal 


Middle  sacral  artery 


Middle  hemorrhoidal 

from  anterior  branch 

of  the  internal  iliac 


Inferior  hemorrhoidal 
from  the  internal  pudic 


Rectum 


Bladder,  upper  surface 


Symphysis 


Fig.  446. — The  blood  supply  of  the  rectum. 

teric.  It  descends  in  the  pelvic  mesocolon  until  it  reaches  the  rectum,  when  it  divides 
into  two  lateral  branches.  These  descend  on  its  surface  to  about  its  middle,  when 
they  subdivide  into  six  or  eight  branches  which  pierce  the  muscular  coat  and  descend 
in  the  submucosa,  one  beneath  each  column  of  Morgagni.  At  the  lower  end  of  the 
rectum  and  anal  canal  they  anastomose  with  the  terminal  branches  of  the  middle 
and  inferior  hemorrhoidal  arteries. 

The  middle  hemorrhoidal  arteries ,  one  on  each  side,  come  from  the  anterior  branch 
of  the  internal  iliac.  They  descend  on  the  lower  part  of  the  rectum  and  supply  the 
posterior  portion  of  the  bladder  and  vagina,  or  prostate  and  seminal  vesicles,  the 
lower  anterior  half  of  the  rectum  and  upper  part  of  the  anal  canal,  and  anastomose 
with  the  superior  hemorrhoidal  branches  above  and  the  inferior  hemorrhoidal  below. 

The  inferior  hemorrhoidal  arteries,  two  or  three  on  each  side,  are  given  off  from 
the  internal  pudic  while  in  Alcock's  canal,  at  the  outer  posterior  portion  of  the  ischio- 
rectal fossa  ;  they  pass  inward  and  downward  to  supply  the  outer  surface  of  the 
levator  ani  and  internal  and  external  sphincters  and  lower  portion  of  the  rectum  and 


RECTUM    AND    ANAL    CANAL. 


441 


anal  canal.  They  anastomose  with  the  middle  and  superior  hemorrhoidals.  They 
are  distributed  more  to  the  posterior  portion  of  the  lower  part  of  the  rectum  and  anal 
canal  while  the  middle  is  distributed  more  to  its  anterior  portion. 

The  viiddle  sacral  artery  passes  down  in  the  median  line  from  the  bifurcation  of 
the  aorta  to  the  tip  of  the  coccy.x,  where  it  ends  in  Luschka's  gland.  It  gives  a  few 
branches  to  the  rectum  at  its  upper  part  but  they  are  supposed  not  to  go  deeper  than 
the  muscular  coat.      It  anastomoses  with  the  superior  hemorrhoidal. 

Veins. — The  veins  of  the  rectum  and  anal  canal  accompany  the  corresponding 
superior,  middle,  and  inferior  hemorrhoidal  arteries.  They  form  two  plexuses,  an 
internal  submucous  plexus  and  an  external  plexus  on  the  surface  of  the  rectum.  The 
internal  plexus  in  the  submucous  coat  begins  at  the  anus  in  fine  venous  capillaries 
which  pass  upward,  mainly  in  the  columns  of  Morgagni,  where  they  form  small  dila- 
tations or  pools  and  unite  into  larger  branches  which  pierce  the  muscular  walls  about 
the  middle  of  the  rectum  to  empty  into  the  main  superior  hemorrhoidal  veins  and 
thence'into  the  inferior  mesenteric. 

The  inferior  hemorrhoidal  veins  receive  branches  from  the  anus  and  outer  surface 


Net-work 
in  rectal 
mucous 
membrane  |V 


•'\ 


r\\- 


Net-work  in  anal 

integument 


w 


Fig.  447. — Lymphatics  of  rectum.    (Gerota.) 

of  the  sphincters  and  levator  ani  muscles  and  pass  thence  to  the  internal  pudic  veins. 

The  middle  hemorrhoidal  vein  drains  the  blood  from  the  external  hemorrhoidal 
plexus  on  the  outer  surface  of  the  lower  half  of  the  rectum  and  empties  into  the  inter- 
nal ihac.  It  anastomoses  with  the  superior  hemorrhoidal  above,  at  about  the  middle 
of  the  rectum,  and  the  inferior  hemorrhoidal  below,  at  the  upper  portion  of  the  anal 
canal.  It  is  thus  seen  that  the  interior  of  the  lower  half  of  the  rectum  is  drained  by 
the  superior  hemorrhoidal  and  its  exterior  by  the  middle  hemorrhoidal.  The  blood 
from  the  upper  part  of  the  anal  canal  drains  into  the  superior  hemorrhoidal,  that 
from  its  lower  part  into  the  inferior  hemorrhoidal.  The  blood  from  the  superior 
hemorrhoidal  veins  empties  into  the  portal  system  through  the  inferior  mesenteric, 
and  the  blood  from  the  middle  and  inferior  into  the  general  venous  system  through 
the  internal  pudic,  internal  iliac,  and  inferior  cava.  These  veins  are  usually  regarded 
as  being  without  valves,  though  the  opposite  view  is  held  by  some. 

Lymphatics. — According  to  Poirier  andCuneo  there  is  a  superior  group  accom- 
panying the  superior  hemorrhoidal  vessels  and  draining  the  mucous  membrane  of  the 
anal  canal  and  rectum  and  terminating  in  the  nodes  of  the  pelvic  mesocolon  after 
traversing  the  pararectal  lymph-nodes  ;  also  a  middle  group  pardy  communicating 


442  APPLIED   ANATOMY. 

with  the  above  through  the  pararectal  lymph-nodes  while  the  remainder  accompany 
the  middle  and  inferior  hemorrhoidal  vessels  and  drain  the  lower  part  of  the  anal 
canal  above  the  white  line.  A  third  group  comes  from  the  skin  of  the  margin  of  the 
anus  and  drains  into  the  inguinal  nodes.  The  pararectal  (anorectal  of  Gerota)  nodes 
may  become  enlarged  in  cases  of  nonmalignant  ulcer  and  can  be  felt  in  the  region  of 
the  ampulla  by  the  finger  introduced  through  the  anus,  thus  leading  to  a  mistaken 
diagnosis  of  carcinoma  (Fig.  447). 

Nerves. — The  anus  is  supplied  by  the  inferior  hemorrhoidal  branch  of  the  inter- 
nal pudic  nerve,  which,  as  shown  by  Hilton,  crosses  the  ischiorectal  space  on  the  outer 
surface  of  the  levator  ani  muscle  and  passes  between  the  internal  and  external  sphinc- 
ters to  emerge  between  them  at  the  white  line,  from  whence  it  sends  filaments  up  on 
the  mucous  membrane  and  down  on  the  skin.  This  explains  the  great  sensitiveness 
of  the  region.  It  also  supplies  the  external  sphincter,  hence  the  association  of  spasm 
with  pain. 

AFFECTIONS   OF   THE   RECTUM   AND   ANUS. 

Examination. — If  the  buttocks  are  drawn  aside  the  mucous  membrane  of  the 
anus  is  everted  and  a  considerable  portion  of  the  anal  canal  becomes  visible.  The 
lower  part  of  the  columns  and  crypts  of  Morgagni  and  the  anal  valves  are  seen.  If 
the  patient  strains  or  bears  down,  the  mucous  membrane  of  the  anal  canal  is  brought 
into  view  in  almost  its  entire  length.  One  is  thus  enabled  to  see  dilated  veins  or 
hemorrhoids,  ulcers,  fissures,  foreign  growths,  both  benign  and  malignant,  and  the 
openings  of  fistulae.  By  means  of  a  speculum  the  entire  anal  canal  can  be  seen.  It 
should  be  introduced  pointing  obliquely  anteriorly,  and  if  it  is  desired  to  view  the 
interior  of  the  rectum  above  after  it  has  passed  the  internal  sphincter  it  is  to  be 
directed  obliquely  upward  and  backward.  In  digital  examination  the  first  resistance 
encountered  is  that  of  the  external  sphincter;  as  its  edge  is  passed  a  sulcus  can  often 
be  felt,  immediately  following  which  the  internal  sphincter  is  passed  and  the  finger 
enters  the  rectum.  The  sulcus  is  about  opposite  the  crypts  of  Morgagni  and  is 
formed  by  the  interval  between  the  contraction  of  the  external  sphincter  below  and 
the  internal  sphincter  blended  with  the  insertion  of  the  levator  ani  above.  It  is  just 
above  Hilton's  white  line. 

Imperforate  Anus. — In  an  early  stage  of  the  development  of  the  embryo  the 
cloaca  is  the  common  termination  of  the  genito-urinary  system  and  the  intestinal 
canal.  Later  the  cloaca  becomes  divided  by  a  septum  into  the  urogenital  sinus  in 
front  and  the  rectum  behind.  A  depression  in  the  skin  called  the  anal  pit  appears 
opposite  the  rectum  and  the  membrane  between  disappears  in  the  fourth  month. 
This  membrane  is  produced  by  the  growing  together  of  the  ectoderm  and  entoderm, 
the  mesoderm  being  pushed  aside.  The  failure  of  this  membrane  to  perforate  forms 
imperforate  anus.  The  method  of  development  explains  the  various  malformations 
of  these  parts.  The  anal  pit  may  be  absent  ;  the  membrane  may  not  perforate  ;  the 
rectum  may  end  in  a  blind  pouch  some  distance  up  from  the  anus  ;  or  it  may  discharge 
through  a  sinus  into  the  bladder  or  vagina. 

Hemorrhoids. — Hemorrhoids  or  piles  are  varicosities  or  dilatations  of  the 
veins  of  the  anus  or  anal  canal.  The  middle  hemorrhoidal  veins  are  not  enlarged 
because  they  do  not  drain  the  mucous  membrane,  they  are  not  inside  but  outside 
the  rectum.  When  the  inferior  hemorrhoidal  veins  are  dilated  they  form  external 
hemorrhoids  and  are  situated  at  the  margin  of  the  anus  below  the  white  line  and 
external  sphincter,  and  they  cannot  be  replaced  in  the  rectum.  When  the  superior 
hemorrhoidal  veins  are  dilated  they  form  internal  piles  (Fig.  448).  The  dilatation 
involves  the  superior  hemorrhoidal  veins  from  the  beginning  of  the  mucous  mem- 
brane at  the  white  line  up  the  entire  length  of  the  anal  canal  and  sometimes  a  short 
distance  up  the  rectum.  There  is  a  natural  tendency  for  external  piles  to  be  covered 
almost  wholly  by  skin  and  for  internal  piles  to  be  covered  solely  by  mucous  mem- 
brane. Inflamed  internal  piles  can  be  pushed  back  in  the  rectum.  If  an  internal 
pile  is  continued  down  over  the  white  line  or  an  external  pile  is  continued  up  over 
the  white  line  then  they  are  called  intero-external  piles.  Hemorrhoids  consist  almost 
wholly  of  dilated  venous  sinuses.  The  existence  of  arterial  hemorrhoids  is  now 
denied  although  small  arterial  branches  are  sometimes  encountered  in  the  ordinary 


RECTUM    AND    ANAL    CANAL. 


443 


venous  pile.  The  strawberry  pile  is  composed  of  venous  capillaries  instead  of  the 
larger  venous  canals  usually  present.  They  bleed  more  freely  than  does  the  ordinary 
venous  pile.  When  external  hemorrhoids  are  operated  on  they  are  usually  throm- 
bosed. They  are  then  incised  and  the  clots  turned  out;  at  other  times  when  not 
intiamed  they  are  excised  and  the  edges  stitched  with  catgut  or  the  wound  packed. 
Internal  piles  are  either  ligated  or  treated  with  the  clamp  and  cautery.  In  applying 
the  ligature  the  base  of  the  pile  is  loosened  below  near  the  white  line  and  detached 
for  some  distance  above  and  then  ligated.  This  is  facilitated  by  the  loose  attachment 
of  the  mucous  membrane.  Bleeding  is  not  marked  because  the  blood-\essels  enter 
the  pile  from  above.  In  Whitehead's  operation,  or  excision  of  the  pile-bearing  area, 
the  mucous  membrane  is  readily  separated  by  blunt  dissection  from  the  parts  beneath 
owing  to  the  laxity  of  the  submucous  tissue;  it  is  then  excised  and  the  cut  edge 
sewn  to  the  skin  at  the  anus. 

Fistula. — Fistula  in  ano  may  start  as  an  ischiorectal  abscess  which  perforates 
internally  into  the  rectum  or  anal  canal  and  externally  through  the  skin.  It  may 
also  start  as  an  ulcer  of  the  mucous  membrane  of  the  rectum  or  crypts  of  Morgagni 
and  then  produce  an  ischiorectal  abscess  which  finally  opens  on  the  skin.  The  most 
common  site  of  the  internal  opening  is  just  above  the  anus  and  below  the  insertion 
of  the  levator  ani.  This  is  in  the  groove  between  the  external  and  internal  sphinc- 
ters.    Sometimes,  however,  the  fistula  pierces  the  levator  ani  and  opens  into  the 


Columns  of  Morgagni 

Internal  sphincter 

Crypts  of  Morgagni 
External  sphincter 

N  Internal  hemorrhoids 

External  hemorrhoids 
Fig.  448. — Hemorrhoids. 

ampulla  of  the  rectum.  As  the  external  opening  is  usually  to  the  outer  side  of  the 
external  sphincter  this  latter  is  divided  in  operating,  as  is  also  a  part  or  all  of  the 
internal  sphincter  if  the  opening  is  high  up.  Incontinence  of  faeces  is  usually  avoided 
if  the  sphincter  is  only  divided  at  one  place  and  at  right  angles  to  its  fibres,  not 
obliquely. 

Anal  fissures  occur  usually  on  the  posterior  wall  of  the  anus  associated  with 
a  hemorrhoid.      Its  location,  involving  the  white  line,  explains  its  great  pain. 

Excision  of  the  Rectum. — The  rectum  can  be  removed  either  by  the  perineal  or 
sacral  route.  1  n  the  perineal  operation  the  incision  is  made  from  near  the  base  of  the  scro- 
tum to  the  coccyx,  surrounding  the  anus.  If  the  incision  is  made  near  the  white  line  the 
external  sphincter  is  saved  and  turned  to  each  side  with  the  skin  flap.  The  external 
sphincter  is  split  anteriorly  as  far  as  the  central  point  of  the  perineum  and  posteriorly  to 
the  coccyx.  The  rectum  being  drawn  forward  the  levator  ani  muscle  is  cut  through  on  its 
sides  and  posterior  surface  about  4  cm.  (i  ^  in.)  above  the  anus,  the  coccyx,  if  necessary, 
being  excised.  The  rectum  is  then  drawn  back,  the  finger  slipped  beneath  the  ante- 
rior portion  of  the  levator  ani,  which  is  farther  from  the  surface  than  the  posterior, 
and  it  is  divided.  These  fibres  practically  constitute  the  recto-urethralis  muscle  of 
Proust.  This  is  near  the  apex  of  the  prostate ;  from  here  up  to  the  peritoneal  re- 
flection or  rectovesical  pouch  the  rectum  is  loosely  attached  but  at  that  point  it  is 
necessary  to  divide  the  rectal  fascia  (a  part  of  the  rectovesical  fascia,  p.  435)  on  the 
sides,  where  it  passes  as  two  strong  fibrous  lateral  pelvi-rectal  bands  below  the  level 
of  the  ureters  to  the  fourth  sacral  foramina,  after  which  the  rectum  can  be  drawn  still 


444 


APPLIED    ANATOMY. 


further  down.  If  it  is  desired  to  go  still  higher  the  peritoneum  may  be  pushed  up  off 
the  rectum  or  it  may  be  opened  and  the  mesorectum  detached  close  to  the  sacrum  so 
as  not  to  injure  its  vessels.  The  detached  rectum  is  then  brought  down,  cut  off, 
and  its  divided  end  sutured  to  the  skin. 

In  approaching  the  rectum  by  the  sacral  route  an  incision  is  made  across  the 
sacrum  opposite  the  third  sacral  segment  and  from  its  right  extremity  (Tuttle)  down 
to  beyond  the  tip  of  the  coccyx.  The  bone  is  chiselled  through  opposite  the  fourth 
sacral  foramina  and  the  flap  turned  down  (Fig.  449).  The  lateral  and  middle  sacral 
arteries  may  have  to  be  ligated.  The  peritoneum,  which  is  visible  in  the  upper 
portion  of  the  wound,  may  then  be  incised  close  to  the  rectum  to  avoid  wounding 
the  ureters,  and  the  mesorectum  detached  close  to  the  sacrum.  This  loosens  the 
rectum,  which  can  then  be  brought  out  and  the  opening  in  the  peritoneum  sewed 


Lower  end  of  sacrum 


Peritoneal  cavity 
opened 


Fig.  449. — Excision  of  the  rectum.     The  sacrum  has  been  divided  and  turned  aside.     The  rectum  is  drawn  to  the 
left,  exposing  the  ureter  and  vas  deferens  and  seminal  vesicle,  and  the  peritoneal  cavity  has  been  opened  above. 

shut.     As  much  of  the  rectum  as  is  desired  is  removed  and  the  cut  ends  united  by  a 
Murphy  button  or  end-to-end  suture. 

In  carcinoma  enlarged  lymph-nodes  may  be  found  in  the  mesorectum  or  hollow 
of  the  sacrum  and  should  of  course  be  removed. 


THE  BLADDER. 

When  fully  distended  the  normal  bladder  contains  approximately  500  c.  c. ,  or  a 
pint.  Its  capacity  varies  much,  and  it  is  capable  of  great  distention  without  rupture. 
In  cases  of  retention  of  urine  it  may  reach  up  to  the  umbilicus  and  contain  a  quart 
or  more,  while  if  its  walls  are  thickened  it  may  be  contracted  and  hold  only  a  few 
ounces.  The  shape  of  the  bladder  is  dependent  on  the  amount  of  dilatation  and  its 
attachments. 

Position. — In  front  of  the  bladder  is  the  symphysis  and  body  of  the  pubes, 
below  and  in  front  is  the  prostate  gland.  Beneath  is  the  posterior  portion  of  the 
prostate,  the  seminal  vesicles,  the  termination  of  the  ureters,  and  the  rectum.  The 
upper  and  posterior  surfaces  are  covered  by  peritoneum  and  small  intestines,  which 
fill  the  rectovesical  pouch.  In  the  female  the  bladder  rests  on  the  upper  half  of  the 
vagina,  and  the  uterus  as  far  as  the  internal  os. 


THE    BLADDER. 


445 


Attachments. — The  bladder  is  fixed  at  its  upper  and  lower  portions.  It  has 
true  ligaments  of  fascia  and  false  ligaments  of  peritoneum.  The  pelvic  fascia  is 
reflected  from  the  levator  ani  muscles  onto  the  bladder  and  prostate.  Its  reflection 
from  the  levator  ani  onto  the  bladder  occurs  at  its  upper  portion  on  each  side  and  is 
called  the  lateral  true  ligaments  (Fig.  450).  The  reflection  from  the  anterior  part  of 
the  bladder  and  prostate  which  goes  to  the  posterior  surface  of  the  pubes  is  called  the 
puboprostatic  ligament  or  anterior  true  ligament  of  the  bladder.     The  urachus  forms  a 


Anterior  false  ligament 
of  peritoneum 


Lateral  false  ligament 
of  peritoneum 

Posterior  false  ligament 
of  peritoneum 


Urachus  or  superior 
ligament 

Puboprostatic  ligament 

Cut  edge  of  peritoneum 

Lateral  true  ligament 


Fig.  450. — View  of  the  interior  of  the  male  pelvis,  showing  the  bladder  attachments. 

superior  ligament.  The  false  ligaments  are  simply  the  peritoneal  reflections.  That 
over  the  urachus  is  the  anterior  false  ligament,  and  those  on  the  sides,  which  are  re- 
flected from  the  bladder  at  about  the  level  of  the  white  line  are  called  the  lateral  false 
ligaments.  When  the  urachus  above  is  detached  the  bladder  is  comparatively  loose. 
Its  firmest  attachment  is  at  its  neck  to  the  prostate  and  to  the  rectum  above  the  pros- 
tate at  the  rectovesical  pouch.  It  is  this  firm  attachment  which  causes  the  mucous 
membrane  of  the  base  of  the  bladder  to  re- 
main smooth  while  the  rest  is  corrugated. 

Shape. — The  shape  of  the  bladder 
is  influenced  by  its  attachments.  As  we 
have  just  seen  these  are  the  urachus  in 
front,  the  neck  below,  and  the  recto\'esical 
pouch  behind  ;  therefore,  as  the  bladder 
collapses  it  assumes  a  conical  shape  with  its 
apex  at  the  neck  and  its  base  running  from 
the  top  of  the  symphysis  anteriorly  to  the 
highest  point  of  attachment  to  the  rectum 
posteriorly.  The  bladder  never  sinks  en- 
tirely below  the  top  of  the  symphysis,  be- 
cause the  urachus  holds  it  there;  as  its  top 
or  fundus  descends  it  sinks  behind  the  sym- 
physis and  slopes  back  to  the  rectum.  If 
the  bladder-walls  are  actively  contracted 
or  much  thickened  it  cannot  readily  col- 
lapse, and  then  retains  a  more  elongated 
shape.     As  it  distends  it  becomes  oval  and  rises  toward  the  umbilicus  (Fig.  451). 

Peritoneum. — In  children  the  bladder  is  practically  an  abdominal  organ  ; 
when  it  is  empty  the  peritoneum  sinks  about  to  the  level  of  the  top  of  the  sym- 
physis, but  when  distended  it  rises  from  2.5  to  6.25  cm.  (i  to  25^  in.)  above.  In 
the  adult  the  top  of  the  bladder  is  held  to  the  top  of  the  symphysis  by  the  urachus, 
and  as  it  becomes  empty  the  upper  surface  descends  until  a  curved  line  is  formed 
from  the  top  of  the  symphysis  downward  and  backward  to  the  rectovesical  pouch, 
which  is  opposite  the  insertion  of  the  ureters  and  corresponds  to  a  point  just  below 


Fig.  451. — The  bladder  in  its  empty  and  distended 
state.  When  distended  the  peritoneal  reflection  on  the 
anterior  abdominal  wall  is  seen  to  be  raised.  The  pos- 
terior or  rectovesical  reflection  remains  nearly  or  quite 
unchanged. 


446  APPLIED    ANATOMY. 

the  extremities  of  the  seminal  vesicles  and  2.5  to  4  cm.  (i  to  1%  in.)  above  the 
posterior  border  of  the  prostate. 

As  held  by  Greig  Smith,  the  main  factor  in  raising  the  peritoneum  from  the 
front  of  the  bladder  above  the  upper  edge  of  the  symphysis  is  its  distention,  and  450 
to  600  c.c.  (15  to  20  oz.)  will  raise  the  fold  2.5  to  5  cm.  (i  to  2  in.). 

When  the  body  is  placed  in  the  Trendelenburg  posture  the  contents  of  the 
bladder  gravitate  toward  the  diaphragm,  and  therefore  push  the  peritoneum  up 
or  away  from  the  upper  border  of  the  symphysis  :  hence  this  position  is  usually 
employed  when  the  bladder  is  to  be  opened  for  operative  purposes.  The  use  of  a 
rubber  bag  in  the  rectum  distended  with  water  has  been  found  to  raise  the  peri- 
toneal folds  so  little  that  its  use  has  been  abandoned  in  favor  of  the  Trendelenburg 
posture. 

Posteriorly  the  rectovesical  pouch  is  approximately  8.75  cm.  (3^  in.)  from 
the  anus,  but  it  may  be  as  little  as  7.5  cm.  (3  in.),  or  as  much  as  10  cm.  (4  in.). 
As  has  already  been  stated  the  attachment  of  the  rectovesical  pouch  to  the  rectum 
is  so  firm  that  whether  the  bladder  is  distended  or  collapsed  its  distance  from  the 
prostate  is  but  little  altered.  It  does  not  change  its  position  markedly  as  does  the 
peritoneum  above  the  pubes.  Waldeyer  (Joessel  and  Waldeyer,  Topog.  Chirurg. 
Anat,  vol.  ii,  p.  554)  gives  1.5  to  2  cm.  (f  to  4  in.)  as  the  greatest  possible 
variation. 

Tapping  the  distended  bladder  is  done  above  the  pubes,  and  care  is  to  be  taken 
to  avoid  wounding  the  peritoneum  ;  this  is  to  be  done  by  knowing  how  its  position 

Postprostatic  pouch  or  bas-fond 

Interureteric  fold  or  ligament 

'Ureteric  fold 

.—-Orifice  of  ureter 
\ 


Orifice  of  the  urethra 


Fig.  452. — View  of  the  interior  of  the  base  of  the  bladder. 

is  influenced  as  just  detailed  above.  In  front  of  the  anterior  bladder  wall  and  between 
it  and  the  posterior  surface  of  the  symphysis  and  transversalis  fascia  is  the  space  of 
Retzius,  filled  with  loose  connective  tissue.  Care  is  to  be  taken  not  to  infect  it 
in  operative  procedures.      It  readily  becomes  infiltrated  in  extravasation  of  urine. 

Rupture  of  the  bladder  occurs  most  often  through  the  peritoneum  of  its  posterior 
surface  when  the  bladder  is  distended.  Extraperitoneal  ruptures  may  occur  when  it 
is  empty,  and  are  usually  the  result  of  wounds  by  foreign  bodies  or  spicules  of  bone 
in  fractures. 

Base  of  the  Bladder. — On  the  interior  of  the  base  of  the  bladder  the  ureters 
open  about  2. 5  cm.  ( i  in. )  posterior  to  the  urethral  orifice,  and  the  same  distance 
(or  more  if  the  bladder  is  distended)  from  each  other.  The  included  triangular 
space  is  called  the  trigone.  Its  mucous  membrane  is  without  the  rugae  possessed  by 
the  rest  of  the  bladder  and,  if  it  is  distended,  is  not  quite  so  pale  in  color.  The 
ureters  pass  obliquely  through  the  walls  a  distance  of  1.25  cm.  (^  in.)  and  cause 
slight  elevations  of  the  mucous  membrane  called  the  plicce  uretericcB  or  ureteric  folds. 
Joining  the  two  ureteral  orifices  is  a  fold  of  mucous  membrane  called  by  Kelly  the 
interureteric  ligament.  The  part  immediately  posterior  to  this  fold  is  \kiQ  postprostatic 
pouch  or  bas-fond.  It  becomes  enlarged  in  prostatics,  and  then  contains  residual 
urine.     Calculi  also  tend  to  lodge  there  (Fig.  452). 

Bladder  Walls. — The  bladder  is  composed  of  a  muscular  wall  covered  exter- 
nally by  the  peritoneum  and  internally  by  the  submucous  and  mucous  coats.  In  the 
undistended  bladder  blood-vessels  can  be  seen  in  the  mucous  membrane,  which  is 


THE    BLADDER. 


447 


in  folds.  These  folds  and  vessels  diminish  or  disappear  when  the  bladder  is  distended. 
The  membrane  at  the  trigone  is  more  firmly  connected  to  the  muscle  beneath  than 
elsewhere  in  the  bladder,  hence  its  smoothness  and  increased  color.  The  muscular 
coat  is  composed  of  two  longitudinal  layers  with  one  more  or  less  transverse  layer 
between.  The  external  layer  is  continuous  with  the  ureters,  and  over  the  prostate 
to  be  attached  to  the  lower  posterior  part  of  the  pubes  under  the  name  of  pubo- 
vesical muscle.  The  circular  fibres  are  continued  around  the  opening  of  the  urethra, 
forming  the  internal  sphincter.  The  openings  of  the  ureters  are  not  closed  by  mus- 
cular action,  but  by  the  interior  pressure.  When  the  bladder  is  distended,  if  the 
ends  of  the  ureters  are  thickened  they  do  not  close  as  the  urine  accumulates,  but 
allow  it  to  back  up  and  distend  the  ureters  and  pelvis  and  even  cause  the  kidney  itself 
to  become  enlarged.  Thus  infection  ascends  from  the  bladder  to  the  kidney  and 
the  ureters  become  distended  until  they  may  equal  in  size  the  small  intestine. 

The  fibres  of  the  muscular  coat  pass  in  \arious  directions,  more  or  less  in  the 
form  of  bundles.  When  these  bundles  become  hypertrophied  they  can  be  seen  as 
distinct  ridges  on  the  interior  of  the  bladder.  In  sounding  they  can  be  felt  and 
recognized  by  the  tip  of  the  sound.  Such  a  condition  is  called  a  7-ibbed  bladder.  If 
the  bladder  becomes  hyperdistended  the  fibres  become  separated  and  the  mucous 
membrane  bulges  out,  forming  a  sac.  It  is  then  called  a  sacculated  bladder.  These 
sacs  are  favorite  lodging  places  for  vesical  calculi.  From  diseases  of  the  prostate 
and  urethra  the  muscular  coat  becomes  thickened.  It  is  then  called  a  hypertrophied 
bladder ;  such  a  one  is  usually  contracted. 

The  bladder  walls  ordinarily  are  quite  thin,  about  3  mm.  (^  in.)  thick.  When 
hypertrophied  they  are  three  or  four  times  as  thick.  When  the  bladder  is  viewed  in 
life  in  abdominal  operations  it  usually  appears  as  a  somewhat  flaccid  sac.  It  does  not 
assume  the  globular  form  until  considerably  distended  and  must  contain  a  moderately 
large  amount  of  urine  before  showing  above  the  symphysis.  The  commonly  flaccid 
condition  of  the  bladder  leads  one  to  think  that  its  emptying  is  largely  favored  by 
the  pressure  of  the  intestines  compressing  it  against  the  floor  of  the  pelvis,  and  that  it 
is  mainly  in  case  of  considerable  distention  or  the  pressure  of  irritation  or  disease  that 
its  own  muscular  coat  is  utilized  for  the  purpose.  This  view  is  strengthened  by  the 
increase  in  flow  when  coughing  and  by  the  occurrence  of  bladder  troubles  (prolapse, 
etc. )  so  soon  as  the  integrity  of  the  pelvic  floor  is  injured,  as  occurs  in  rupture  of  the 
perineum  from  childbirth.  The  laxity  of  the  bladder  walls  allows  it  to  spread  side- 
wise  to  the  neighborhood  of  the  inguinal  rings,  and  it  has  frequently  been  found  in 
the  inguinal  canal  and  has  been  wounded  in  operating  for  hernia.  The  urethral  ori- 
fice in  the  male  is  about  6.25  cm.  (2^  in.)  from  the  surface  at  the  upper  margin  of 
the  symphysis  in  a  downward  and  backward  direction ;  with  the  body  in  a  vertical 
position  it  might  be  said  to  lie  on  a  level  with  the  middle  of  the  symphysis  if  the 
bladder  is  empty,  lower  if  the  bladder  is  distended,  and  slightly  higher  if  the  rectum 
is  distended.  It  is  therefore  within  easy  reach  of  the  finger  inserted  through  a  supra- 
pubic incision. 

The  Bladder  in  the  Female. — In  the  female  the  vesico-uterine  pouch  reaches 
the  level  of  the  internal  os  and  the  bladder  is  in  contact  with  the  cervix  from  there 
down  to  the  cervico vaginal  junction  or  anterior  fornix.  From  here  it  is  in  contact 
with  the  anterior  vaginal  wall  along  its  upper  half.  The  trigone  extends  from  the 
middle  of  the  anterior  vaginal  wall,  which  marks  the  internal  orifice  of  the  urethra, 
to  2  cm.  (3/^  in. )  below  the  cervicovaginal  junction,  the  spot  where  the  ureters  enter 
the  bladder  walls.  The  absence  of  the  prostate  causes  the  bladder  to  be  lower  in  the 
female  and  the  level  of  the  internal  urethral  orifice  is  opposite  the  lower  border  of  the 
symphysis.  It  also  is  smaller  in  the  female  and  does  not  show  itself  so  readily  above 
the  symphysis  on  distention.  Vesicovaginal  fistulae  frequently  occur  as  the  result  of 
injuries  during  childbirth,  cancerous  ulceration,  etc.  They  are  located  on  the  anterior 
wall  of  the  vagina  above  its  middle.  Calculi  can  be  extracted  through  an  incision 
in  the  median  line  of  the  anterior  vaginal  wall  above  its  middle.  The  commence- 
ment of  the  ureters  can  also  be  palpated  on  each  side  of  the  cervix  anteriorly  and 
impacted  calculi  may  be  removed  at  that  point.  The  bladder  is  connected  with  the 
cervix  and  vagina  posteriorly  by  comparatively  loose  connective  tissue  so  that  they 
can  be  readily  separated  by  blunt  dissection  as  far  up  as  the  internal  os. 


448  APPLIED    ANATOMY. 

Cystoscopic  Examination. — The  shortness  and  distensibihty  of  the  female 
urethra  make  the  examination  of  the  interior  of  the  female  bladder  much  easier  than 
that  of  the  male.  For  purposes  of  examination  it  is  distended  either  with  air  or 
water.  In  order  to  distend  it  with  air  it  is  either  injected  directly  with  a  rubber  bulb 
or  the  patient  is  put  in  the  knee-chest  position,  or,  if  on  the  back,  the  pelvis  is  ele- 
vated, so  that  the  intestines  gravitate  toward  the  diaphragm.  If  a  speculum  is  then 
introduced  and  the  obturator  withdrawn  the  bladder  at  once  distends.  The  walls  of 
the  bladder  are  whitish  in  color  with  small  vessels  running  over  them.  The  base 
(trigone)  of  the  bladder  is  redder  than  the  surrounding  walls.  The  muscular  fas- 
ciculi are  often  seen  as  distinct  ridges  and  the  mucous  membrane  may  be  thrown  into 
folds.  The  internal  orifice  of  the  urethra  in  the  female  is  just  below  the  lower  border 
of  the  symphysis.  The  ureteral  orifices  can  be  seen  as  slightly  ele\'ated  papillae  2.5 
cm.  or  more  behind  the  urethral  orifice  and  30°  to  its  side,  the  trigone,  when  the 
bladder  is  not  distended,  making  an  equilateral  triangle,  with  the  urethra  and  ureteral 
papillae  at  its  angles  (Fig.  453). 

Operations. — Most  of  the  operations  on  the  bladder  are  done  from  above.  To 
relieve  distention  tappi7ig  is  done  with  a  fine  trocar  or  aspirating  needle.  It  is  to  be 
inserted  close  to  the  upper  margin  of  the  symphysis  and  passed  downward  and  back- 

Fig  4>;^ — The  picture  on  the  left  demonstrates  a  normal  mucous  membrane  and  ureteral  orifice.  On  the 
right  the  ureteral  orifice  will  be  observed  to  be  small,  round,  atrophic,  and  functionless.  (Drawn  from  a  case  ot 
Dr.  Benj.  A.  Thomas*  by  Mr.  Louis  Schmidt.) 

ward.  Cystotomy  is  performed  through  the  median  line.  In  making  the  incision 
three  layers  of  fat  are  divided;  first,  the  superficial  fascia  between  the  skin  and  muscles; 
second,  the  fatty  pad  between  the  posterior  surface  of  the  muscles  and  the  transver- 
salis  fascia;  and  third,  the  prevesical  fat  of  the  space  of  Retzius  beneath  the  trans- 
versalis  fascia  and  between  the  anterior  wall  of  the  bladder  and  the  symphysis  pubis. 
Tumors.— Growths  and  prostatic  enlargements  are  often  operated  on  supra- 
pubically.  These  are  usually  easily  within  reach  of  the  finger.  In  incising  the  blad- 
der the  anterior  vesical  veins  are  to  be  avoided  by  keeping  in  the  median  line. 

THE  PROSTATE. 

The  normal  prostate  gland  is  of  the  shape  of  a  large  chestnut.  It  is  3  to  4  cm. 
(i  ^  to  1 5^  in. )  wide,  2. 5  to  3  cm.  ( i  to  1 34:  in. )  long,  and  3  cm.  ( 1 14:  in. )  thick.  An 
indistinct  furrow  on  its  under  surface  separates  it  into  two  lateral  lobes.  There  is  no 
median  lobe,  as  the  prostatic  tissue  is  continued  uninterrupted  across  the  median 
line.  For  clinical  purposes  we  may  consider  the  prostate  as  having  an  apex,  a  vesi- 
cal surface  or  base,  and  a  rectal  or  posterior  surface. 

The  vesical  surface  is  pierced  a  little  anterior  to  its  centre  by  the  urethral  open- 
ing, which  leads  to  the  apex.      Entering  below  and  posteriorly  at  the  fissure  are  the 

*  Diagnosis  of  Renal  Disease  and  Sufficiency,  Dr.  Benjamin  A.  Thomas,  Annals  of 
Surgery,  May,  1903. 


THE  PROSTATE. 


449 


ejaculatory  ducts.  These  enter  close  together  near  the  median  line  and  pass  upward 
and  forward  to  enter  the  under  surface  of  the  prostatic  urethra  about  its  middle.  It 
is  to  the  part  of  the  prostatic  tissue  between  the  ejaculatory  ducts  below  and  the 
interior  of  the  bladder  above,  just  posterior  to  the  urethral  orifice,  that  the  name 
middle  lobe  has  been  applied.  This  part  contains  a  collection  of  glands  called  by 
Albarran  (Albarran  and  Motz:  Annales  des  Mai.  Ginito-  Urinaires,  July,  1902)  the 
prespermatic  group.  Just  beneath  the  mucosa  behind  the  urethra  is  another  group 
which  he  calls  the  subcervical  group.  In  so-called  enlargements  of  the  middle  lobe 
these  glands  form  the  bulk  of  the  tissue.  A  slight  enlargement  produces  a  bar,  a 
considerable  enlargement  produces  a  projecting  growth  which  may  even  be  peduncu- 
lated. The  glandular  portion  of  the  prostate  in  addition  to  that  just  described  pos- 
terior to  the  urethral  orifice  is  located  centrally,  and  the  fibromuscular  part  of  the 
gland  is  mostly  outside  of  the  glandular  portion,  surrounding  it  and  passing  across 


Prostatic  veins 

Deep  layer  tri- 
angular ligament 

Superficial  layer 
triangular  ligament 


Rectovesical  fascia 

Layer  covering 
seminal  vesicles 
Layer  covering 
the  rectum 

Internal  sphincter 

Sheath  of  prostate 

Capsule  of  prostate 

Separable  space 

Rectal  layer  of  fascia 

Recto-urethralis 
muscle 

Deep  transverse 
perineal  muscle 

Internal  sphincter 

Cowper's  gland 

External  sphincter 

Superficial  transverse 
perineal  muscle 


Membranous  urethra 
Fig.  454. — Tne  prostate  and  its  fascias. 


the  median  line  in  front  of  the  urethra  to  form  the  anterior  commissure.  Some  fibres 
cross  the  median  line  posteriorly,  forming  an  indistinct  posterior  commissure. 

Sheath  and  Capsule. — The  prostate  is  surrounded  by  a  distinct  firm  fibrous 
sheath  which  is  continuous  with  the  rectovesical  fascia  (aponeurosis  of  Denon- 
villiers).  At  the  upper  portion  this  blends  with  the  fascia  covering  the  bladder, 
anteriorly  it  forms  the  puboprostatic  ligaments,  below  it  is  continuous  with  the  deep 
layer  of  the  triangular  ligament  of  the  perineum,  posteriorly  it  is  continuous  with 
the  rectovesical  fascia  and  covers  and  binds  the  seminal  vesicles  to  the  bladder. 
The  prostatic  plexus  of  veins  is  imbedded  in  this  fibrous  sheath.  (J.  W.  Thomson 
Walker,   Brit.  Med.  Jour.,  July  9,  1904.)      (Fig.  454). 

Between  the  veins  and  the  glandular  tissue,  and  covering  the  latter,  is  what  has 
been  called  by  Sir  Henry  Thompson  and  W.  G.  Richardson  ("Development  and 
Anatomy  of  the  Prostate  Gland  ' ' )  the  capsule.  It  is  a  comparatively  thin  layer  of 
fibrous  tissue,  insignificant  and  incomplete  in  places,  which  penetrates  the  substance 
of  the  gland.  It  adheres  to  and  is  removed  with  the  lobes  of  the  enlarged  prostate 
in  prostatectomy. 

C.  S.  Wallace  {Brit.  Med.  Jour.,  1904,  i.,  p.  239)  holds  that  what  Sir  H.  Thompson 
has  called  the  capsule  is  the  thin,  muscular,  outer,  nonglandular  portion  of  the  organ. 
29 


450  APPLIED    ANATOMY. 

Relations. — Tlie  apex  rests  on  the  posterior  layer  of  the  triangular  ligament 
I  to  2  cm.  (^4  to  3/^  in.)  behind  and  a  little  below  the  subpubic  angle  and  just 
inside  the  upper  end  of  the  anal  canal.  This  is  about  3  to  4  cm.  (i}(  to  i}4  in.) 
above  the  white  line  of  Hilton  and  the  prostate  is  immediately  felt  by  the  finger  as 
soon  as  it  enters  the  rectum.  The  prostate  lies  on  the  rectum,  so  that  it  is  readily 
accessible.  Its  apex  being  about  3  cm.  (i^  in.)  from  the  mucocutaneous  white  line, 
its  upper  edge  would  be  6  cm,  {2}4  in.)  and  the  rectovesical  pouch  8.75  cm.  (31^  in.) 
above  this  line.  Thus  all  these  structures  are  usually  within  reach  of  the  finger.  In 
the  median  line,  extending  to  each  side,  the  vasa  deferentia  and  seminal  vesicles,  if 
diseased,  as  they  sometimes  are  in  tuberculous  affections,  can  readily  be  felt,  but  when 
healthy  are  too  soft  to  be  easily  distinguished.  On  each  side  is  the  levator  ani 
muscle,  which  embraces  the  prostate  as  far  forward  as  the  membranous  urethra, 
where  it  practically  blends  with  the  deep  transverse  perineal  and  compressor  urethrae 
muscles  (see  recto-urethralis  muscle — Perineum,  page  475). 

Structure. — The  greater  portion  of  the  prostate  is  composed  of  unstriped 
muscular  tissue,  which  is  not  only  arranged  peripherally  but  sends  prolongations 
inward,  forming  spaces  in  which  the  glandular  tissue  is  lodged.  There  is  also  a  layer 
surrounding  the  vesical  opening  of  the  urethra.  The  action  of  this  latter  muscle  is 
probably  to  act  as  a  true  sphincter  to  retain  the  urine  in  the  bladder.  It  also  by  its 
contraction  prevents  the  regurgitation  of  the  semen  into  the  bladder. 

Veins. — In  the  urethral  and  vesical  portions  of  the  prostate  are  numerous 
veins.  These  in  the  old  become  Aaricose,  hence  the  frequency  of  bleeding  in  old 
prostatic  cases.  Around  the  anterior  portion  of  the  prostate  and  laterally  pos- 
teriorly lies  the  prostatic  venous  plexus.  Into  it  anteriorly  empties  the  dorsal  vein 
of  the  penis;  from  above  it  receives  the  vesical  veins,  and  in  those  advanced  in  age 
it  communicates  also  with  the  hemorrhoidal  plexus  posteriorly,  Fenwick  has  shown 
(Jour,  of  Anat.  xix.  1885)  that  in  the  young  these  veins  possess  valves  which 
become  incompetent  as  age  supervenes.  The  prostatic  plexus  unites  in  a  single 
large  vein  on  each  side  which  empties  into  the  internal  iliac  vein. 

Hypertrophy. — This  is  the  most  common  affection  of  the  prostate.  According 
to  Mansell  MouUin  it  always  begins  in  the  glandular  elements.  It  is  of  two  kinds, 
fibrous  and  glandular.  Both  start  as  glandular  but  the  former  in  some  cases 
predominates  and  the  glandular  element  atrophies  and  leaves  a  comparatively  small 
hard  fibrous  prostate.  The  glandular  character  of  median  growths  has  already  been 
explained  on  page  449  as  originating  from  the  prespermatic  and  subcervical  groups 
of  Albarran. 

Glandular  hypertrophy  of  the  lateral  lobes  forms  the  ordinary  large  prostates  for 
which  prostatectomy  is  performed.  The  bleeding,  which  is  so  common  in  these 
cases  of  enlarged  prostate,  is  due  to  the  varicose  condition  of  the  veins  around  the 
posterior  portion  of  the  urethra  and  vesical  mucous  membrane. 

Prostatectomy. — This  consists  in  removing  the  hypertrophied  glandular  ele- 
ments.     It  is  performed  either  suprapubically  or  through  the  perineum. 

When  done  through  a  suprapubic  incision  a  median  enlargement  (so-called 
median  lobe)  can  readily  be  removed  by  dividing  the  mucous  membrane  with  the 
finger-nail  or  scissors  and  shelling  the  growth  out  with  the  finger.  In  this  case  there 
is  practically  no  sheath  to  go  through  and  the  amount  of  bleeding  will  be  proportion- 
ate to  the  varicose  condition  of  the  veins.  If  large  lateral  growths  are  to  be  removed 
then  there  is  still  no  fibrous  sheath  to  be  entered,  but  only  the  thin,  filmy  capsule  and 
fibromuscular  layer  of  prostatic  tissue  covering  the  hypertrophied  glandular  masses: 
hence  for  its  division  Freyer  uses  his  finger-nail  only.  As  the  fibrous  sheath  is  not 
divided  there  is  no  bleeding  from  the  prostatic  venous  plexus  in  its  layers. 

In  perineal  prostatectomy  two  methods  are  used.  In  the  first  the  membranous 
urethra  is  opened  by  a  median  incision  and  then  a  lateral  cut  made  into  the  enlarged 
prostate  on  each  side.  The  finger  is  then  introduced  and  the  hypertrophied  glandu- 
lar masses  enucleated  with  the  finger.  In  the  second  method  a  curved  or  A-shaped 
incision  is  made  from  the  central  tendon  of  the  perineum  toward  each  side  between 
the  rectum  and  tuberosities.  The  sphincter  ani  is  then  detached  from  the  central 
tendon  and  pushed  back  while  the  transverse  perinei  muscles  are  pulled  forward. 
The  muscular  fibres  between  the  rectum  and  membranous  portion  of  the  urethra 


THE  PROSTATE. 


451 


(page  438,  recto-urethralis  muscle)  are  then  divided  and  the  rectum  pushed  back 
(Fig.  455).  This  exposes  the  prostate;  its  outer  capsule  or  sheath  is  then  incised  and 
the  growth  removed  with  the  finger  or  forceps.  In  order  to  prevent  injury  to  the 
ejaculatory  ducts  Young  enucleates  through  two  lateral  incisions,  thus  leaving  a  middle 
strip  in  which  the  ejaculatory  ducts  are  contained.  According  to  Gosset  and  Proust 
(^Manuel  de  la  Prostatedomie,  Paris,  1903)  the  fascia  between  the  prostate  and  rectum 
(aponeurosis  of  Denonvilliefs)  is  composed  of  two  layers,  an  anterior  one  on  the 
prostate — its  sheath — and  another  posterior  one  on  the  rectum.  When  the  recto- 
urethralis  muscle  is  divided  the  incision  should  likewise  divide  the  posterior  or  rectal 
layer,  which  is  then  pushed  back  with  the  rectum.      Thus  is  formed  the   ' '  ^space 


Ischiocavemosus 


•  Bulbocavernosus 
Central  point  of 
perineum 

Superficial  transverse 
.perineal  muscle 


Membranous  urethra 
Prostate 

Recto-urethralis  muscle 
Levator  ani 

Lower  end  of  rectum 

External  sphincter  ani 


Fig.  4SS. — ^The  parts  involved  in  prostatectomy.  The  external  sphincter  ani  has  been  divided  at  the  central 
point  of  the  perineum  and  with  the  lower  portion  of  the  rectum  has  been  drawn  back,  thus  putting  the  recto-ure- 
thralis muscle  on  the  stretch  and  exposing  the  prostate  to  each  side. 


decoUable  retroprostatique ' '  or  separable  space  and  the  anterior  layer  or  sheath  of 
the  prostate  is  exposed. 

Abscess. — Inflammation  and  abscess  of  the  prostate  follow  injury  and  infection 
from  the  introduction  of  catheters  or  bougies  and  also  from  gonorrhoea.  The  hot  and 
enlarged  gland  can  readily  be  felt  through  the  rectum.  The  bladder  and  rectal 
-symptoms  are  marked.  Pus  tends  to  discharge  either  into  the  urethra  or  rectum, 
more  rarely  it  may  point  in  the  perineum  behind  the  triangular  ligament  and  in  front 
of  the  anus.  Abscesses  breaking  into  the  urethra  may  leave  a  large  cavity,  which 
becomes  a  receptacle  for  pus,  urine,  and  calculi,  and  hastens  a  fatal  issue.  When 
breaking  into  the  rectum  intractable  fistulae  may  result.  Prostatic  abscesses  should 
be  opened  by  an  incision  in  the  perineum  just  anterior  to  the  anus,  the  finger  being 
introduced  into  the  rectum  to  avoid  wounding  it. 


452 


APPLIED    ANATOMY. 


THE  SEMINAL  VESICLES. 

The  seminal  vesicles  are  about  5  cm.  (2  in.)  long  and  lie  on  the  bladder  above  the 
prostate.  They  diverge  on  each  side  toward  the  ureters,  which  they  overlap  and  which 
intervene  between  the  vesicles  and  bladder  wall.  The  vasa  deferentia  run  along  the 
inner  border  of  the  vesicles  and  join  the  ducts  from  the  vesicles  to  form  the  common 
ejaculatory  ducts  just  before  entering  the  posterior  portion  of  the  prostate.  Their  up- 
per portion  is  covered  by  the  peritoneum  of  the  rectovesical  pouch.  They  are  fastened 
to  the  bladder  by  the  rectovesical  fascia,  and  are  in  close  relation  with  the  prostatic 
plexus  and  vesical  veins.  They  are  within  reach  of  the  finger  introduced  through  the 
anus  and  may  be  massaged  and  their  contents  expressed.  They  have  been  excised  for 
tuberculous  disease.  When  normal  they  are  not  readily  recognized  by  touch,  but  in 
disease  are  easily  felt.     Operations  on  them  are  conducted  like  those  of  perineal  pros- 


Bulbocavernosus 


Ischiocavernosus 

Cut  edge  recto- 
urethralis  muscle 

Superficial  transverse 
perineal  muscle 


Internal  pudic  artery 
and  nerve 


Vas  deferens 


Rectum,  drawn  back 


---Bulb 


Cut  edge  sphincter  ani 
Membranous  urethra 


Fig. 


456. — The  prostate  gland  and  seminal  vesicles  exposed  by  dividing  the  external  sphincter  and  recto-urethralis 
muscle  and  pulling  the  rectum  forcibly  back. 


tatectomy,  but,  as  they  lie  higher,  beyond  the  prostate,  it  is  almost  impossible  to  bring 
them  well  into  view  for  operative  purposes.  The  seminal  vesicles  are  nothing  more 
than  blind  diverticula  from  the  vasa  deferentia  and  partake  of  its  diseases.  The  epi- 
didymis, vas  deferens,  seminal  vesicles,  and  prostate  are  all  frequently  involved  in 
tuberculosis  of  the  genito-urinary  tract  (Fig.  456).    • 


THE  VAS  DEFERENS. 

When  the  vas  deferens  leaves  the  internal  abdominal  ring  it  winds  around  the 
outer  side  of  the  deep  epigastric  artery  and  dips  down  over  the  brim  of  the  pelvis  4 
or  5  cm.  (i^  to  2  in.)  posterior  to  the  pubic  spine.  It  then  runs  downward  and 
backward  on  the  side  of  the  pelvis,  under  the  peritoneum,  crossing  superficially  the 


THE  UROGENITAL    SYSTEM. 


453 


obliterated  hypogastric  artery,  the  obturator  vessels  and  nerve,  the  vesical  arteries, 
from  the  inferior  of  which  it  receives  the  artery  of  the  vas,  and  finally  the  ureter.  In 
its  pelvic  course  the  vas  deferens  is  not  often  the  subject  of  surgical  interference 
except  in  cases  of  undescended  testis.  In  these  cases  it  is  often  loosened  from  the 
firm  but  thin  fibrous  bands  which  retain  it  in  place,  after  which  it  is  readily  drawn 
forward  to  allow  the  testicle  to  descend. 

DEVELOPMENT   OF  THE    UROGENITAL  SYSTEM. 

In  the  early  stages  of  development  of  the  human  embryo  there  arises  from  the 
parietal  mesothelium  on  each  side  a  tube  known  as  the  lVolffia7i  diid  with  a  collec- 
tion of  tubules  known  as  the  Wolffian  body.  This  reaches  its  full  development  in  the 
seventh  week.  On  one  side  of  the  Wolffian  body  develops  the  sexual  gland,  which 
later  becomes  either  a  testicle  or  ovary.  At  the  caudate  extremity  of  the  Wolffian 
body  develops  the  kidney  by  the  end  of  the  second  month.  At  this  time  the  bladder 
is  connected  by  the  urachus  with  the  stalk  of  the  allantois.  The  lower  end  of  the 
bladder  is  connected  with  the  extremity  of  the  intestinal  tract  through  a  dilatation 


Uiogenital  sinus 

Intestine 

Cloaca 


Hydatid  of  Morgagni 

Testicle 

Epididymis 

Duct  of  Rathke 

(Irgan  of  Giraldes 

Gubernaculum 

Vas  deferens 

Ureter 

Urachus 

Ductof  Miiller 

atrophied 

Bladder 


Seminal  vesicles 


BEFORE  JDIFFERENTIATION  MALE 

Fig.  457. — The  development  of  the  genital  organs. 


FEMALE 


called  the  urogenital  simis.  The  union  of  the  urogenital  sinus  and  intestine  forms  the 
cloaca.  At  the  time  the  Wolffian  body  is  developing  there  appears  alongside  of  it  a 
tube  called  the  duct  of  Miiller.  It  atrophies  in  the  male  but  in  the  female  becomes 
the  Fallopian  tube,  -uterus,  and  vagina.  The  ureter  is  de\'eloped  and  becomes  con- 
nected with  the  lower  portion  of  the  bladder  (Fig.  457). 

The  Wolffian  duct  and  duct  of  Miiller,  until  about  the  third  month,  empty  into 
the  urogenital  sinus.  Differentiation  of  the  sexes  begins  about  the  third  month  and 
is  well  ad\anced  in  the  fifth.  The  sexual  gland  in  the  male  becomes  the  testicle  and 
passing  from  its  lower  end  is  seen  the  gubernaculum.  In  the  female  it  becomes  the 
ovary  and  the  round  ligament  passes  from  its  lower  end.  The  Wolffian  body  after 
performing  temporarily  the  functions  of  a  kidney  disappears,  leaving  sometimes  a  small 
cyst  attached  to  the  upper  part  of  the  epididymis  in  the  male  and  in  the  broad  ligament 
near  the  ovary  in  the  female,  known  as  the  hydatid  of  Morgagni  {^stalked  hydatid). 
Its  lower  portion  has  as  its  remains  some  short  closed  tubes  in  the  tail  of  the  epidid- 
ymis known  as  the  paradidymis  or  organ  of  Giraldes  in  the  male  and  the  paro- 
ophoron of  the  broad  ligament  in  the  female.  The  Wolffian  duct,  while  forming  the 
vas  deferens  and  part  of  the  epididymis  in  the  male,  forms  the  atrophied  paroophoron 
in  the  female  to  the  inner  side  of  the  ovary. 


454  APPLIED    ANATOM\ . 

The.  parova}  iwn  or  organ  of  Rosenmliller  is  the  remains  of  the  middle  set  of 
Wolfftan  tubules  and  in  the  male  forms  the  epididymis.  In  the  female  it  is  almost 
always  present  as  a  horizontal  tube  with  shorter  tubes  connected  with  it,  between  the 
layers  of  the  broad  ligament  near  the  ovary.  The  Wolffian  duct  may  persist  as  a 
small  tube  in  the  broad  ligament  close  to  the  uterus  and  vagina  and  known  as  the 
duct  of  Gartner.  The  ducts  of  Miiller  in  the  male  atrophy  and  form  the  sinns 
pocularis  of  the  prostate.  Part  of  them  may  persist  patulous  as  the  dzict  of  Rathke. 
In  the  female  they  form  the  Fallopian  tubes,  uterus,  and  vagina. 

A  knowledge  of  the  development  of  the  urogenital  tract  enables  one  to  under- 
stand how  many  of  its  congenital  deformities  and  subsequent  affections  are  produced. 
Extrophy  of  the  bladder,  epispadias,  hypospadias,  and  various  forms  of  hermaphro- 
ditism result  when  the  walls  of  the  bladder  and  urethra  and  external  genitals 
fail  to  develop  in  the  median  line.  Should  the  urachus  not  close,  a  fistulous 
tract  leads  from  the  bladder  to  the  umbilicus  from  which  urine  discharges.  Cysts 
may  also  form  in  its  course.  Should  the  partition  between  the  rectum  within  and  the 
dimple  of  the  anus  without  not  become  absorbed  there  is  formed  one  of  the  varieties 
of  imperforate  anus.  In  some  cases  the  rectum  empties  into  the  urethra  or  bladder, 
thus  forming  a  cloaca.  Should  the  testicle  become  arrested  in  its  descent  from  the 
region  of  the  kidney  It  forms  what  is  known  as  undescended  testicle.  It  may  be 
arrested  within  the  abdominal  cavity,  in  the  inguinal  canal,  or  near  the  external 
abdominal  ring. 

The  paroophoron  gives  rise  to  cysts  which  have  a  tendency  to  develop  between 
the  layers  of  the  broad  ligament  and  are  papillomatous  inside.  The  parovarium  also 
gives  rise  to  cysts  which  likewise  tend  to  burrow  between  the  layers  of  the  broad  lig- 
ament. Cysts  arising  from  Gartner's  duct  are  sometimes  found  in  the  vagina.  In 
the  male,  cysts  arising  from  the  Wolffian  duct  are  :  ( i )  encysted  hydrocele  of  the 
testicle  ;  and  (2)  general  cystic  disease  of  the  testicle.  Cysts  arising  from  the  per- 
sistence in  the  male  of  the  duct  of  Miiller  have  also  been  observed  in  the  prostate 
and  seminal  vesicles,  but  they  are  exceedingly  rare. 

THE  FEMALE  GENERATIVE  ORGANS. 

The  female  pelvic  organs  are  so  often  the  subject  of  operative  procedures  that 
an  exact  knowledge  of  the  relations  of  the  uterus,  vagina,  ovaries.  Fallopian  tubes, 
round  and  broad  ligaments,  and  ureters  is  of  great  importance. 

THE   UTERUS. 

The  normal  unimpregnated  uterus  is  approximately  7.5  cm.  (3  in.)  long,  5  cm. 
(2  in.)  broad,  and  2.5  cm.  (i  in.)  thick.  It  consists  of  a  fundus,  body,  and  neck. 
Its  fundus  is  that  part  above  a  line  joining  the  two  openings  of  the  Fallopian  tubes  at 
the  cornua.  The  neck  of  the  uterus  or  cervix  embraces  2.5  cm.  (i  in.)  of  its  lower 
portion.  Between  the  neck  and  fundus  is  the  body.  The  cavity  of  the  uterus  is 
small,  its  anterior  and  posterior  walls  being  almost  in  contact,  while  laterally  it 
extends  toward  the  Fallopian  tube  openings.  The  opening  through  the  cervix  is  the 
cervical  canal  ;  it  opens  into  the  vagina  by  the  external  os  and  into  the  uterus  by  the 
internal  os  ;  it  is  round  in  shape.  The  external  os  in  the  nullipara  is  round  but  in 
those  who  have  borne  children  it  is  a  transverse  slit.  The  cer\'ical  canal  is  narrowed 
at  both  the  internal  os  and  the  external  os  while  it  is  larger  between  ;  hence  in 
passing  instruments  into  the  uterus  they  traverse  with  difficulty  the  external  os  and 
the  internal  os  but  pass  readily  between  the  two  and  into  the  uterine  cavity  beyond. 

The  cervix  enters  the  upper  end  of  the  vagina  in  its  anterior  wall  and  presents 
downward  and  backward  (Fig.  458),     Its  posterior  lip  is  longer  than  the  anterior. 

Position. — The  uterus  is  most  firmly  fixed  to  the  vagina  and  its  upper  portion 
is  the  most  movable.  Lying  between  the  bladder  anteriorly  and  intestines  and 
rectum  posteriorly  its  position  varies  with  the  condition  of  those  organs.  Normally 
it  inclines  anteriorly  (anteversion).  It  lies  in  contact  with  the  bladder,  no  intestines 
intervening.     With  an  empty  bladder  it  may  point  almost  horizontally  just  above  the 


THE    UTERUS. 


455 


top  of  the  symphysis  pubis,  the  external  os  being  almost  at  the  same  level.  As  the 
bladder  distends  and  the  rectum  becomes  empty  the  fundus  rises  more  and  more 
until  the  axis  of  the  uterus  may  coincide  with  that  of  the  vagina,  or  even  pass 
beyond  ;  and  then  it  is  said  to  be  retroverted.  The  uterus  is  normally  almost 
straight  or  slightly  bent  forward.  As  the  result  of  disease  it  becomes  more  or  less 
sharply  bent  at  the  region  of  the  internal  os  either  forward  or  backward.  It  is  then 
said  to  be  anteflexed  or  retroflexed.  When  retroflexed  the  fundus  can  frequently  be 
felt  as  a  round  hard  mass  behind  the  upper  posterior  portion  of  the  vagina. 

Attachments. — In  addition  to  being  attached  to  the  vagina  the  uterus  has  cer- 
tain folds  or  ligaments  which  pass  from  it  to  the  surrounding  parts.  Anteriorly  the 
peritoneum  is  reflected  from  the  uterus  at  the  level  of  the  internal  os  to  the  bladder, 
forming  the  uterovesical  fold.  Posteriorly  the  peritoneum  descends  from  the  uterus 
over  the  posterior  surface  of  the  upper  portion  of  the  vagina  for  i  or  2  cm.  {y^  in.^ 
and  thence  onto  the  rectum  constituting  the  rectovagmal  or  recto-iderine  fold.  The 
deep  pouch  so  formed  is  called  Douglas' s pouch.     On  each  side  are  three  ligaments; 


Round  ligament 


Broad  ligament 


Uterovesical  fold 

Bladder 

Symphysis 

Urethra 


Infundibulopelvic  or 
suspensory  ligament 
of  ovary 


Fallopian  tube 
Ovary 

■  rosacral  ligament 

■  ernal  os 
Douglas's  pouch 
Recto-uterine  fold 
Rectum 


Vagina 


Fig.  458. — Lateral  view  of  the  interior  of  the  female  pelvis. 

the  broad  liga?nent  is  the  largest  and  most  important.  The  two  broad  ligaments  and 
uterus  form  a  diaphragm  which  extends  from  one  side  of  the  pelvis  directly  across  to 
the  other,  thus  dividing  it  into  anterior  and  posterior  compartments.  On  the  side  of 
the  uterus  the  broad  ligament  extends  from  the  round  ligament  and  Fallopian  tube 
above  down  to  below  the  level  of  the  internal  os.  The  anterior  layer  blends  with  the 
uterovesical  fold  at  the  level  of  the  internal  os,  while  the  posterior  goes  to  the  bottom 
of  the  pouch  of  Douglas.  It  passes  outward  to  be  attached  to  the  sides  of  the  pelvis 
from  the  external  iliac  vein  above  down  to  the  floor  of  the  pelvis.  Between  the  two 
peritoneal  layers  of  the  broad  ligament  at  its  top  is  the  Fallopian  tube,  a  little  lower 
on  the  posterior  surface  is  the  ovary,  going  to  the  ovary  are  the  ovarian  vessels; 
lower  still  is  the  round  ligament ;  and  running  in  the  base  of  the  broad  ligament  are 
the  uterine  artery  and  ureter.  At  its  pelvic  attachment  the  broad  ligament  widens 
out,  having  the  round  ligament  as  its  anterior  edge  and  the  infundibulopelvic  or  sus- 
pensory ligament  of  the  ovary  as  its  posterior  edge.  This  latter  runs  not  to  the 
uterus  but  to  the  fimbriated  extremity  of  the  Fallopian  tube  and  ovary  and  contains 
the  ovarian  vessels.     A  little  posterior  is  the  uteroso.cral  ligament  (recto-uterine) ;  it 


4S6 


APPLIED    ANATOMY 


runs  from  the  uterus  backward  and  contains  muscular  and  fibrous  tissue,  the  mus- 
cular tissue  goes  to  the  rectal  wall  while  the  fibrous  goes  to  be  attached  to  the  second 
and  third  sacral  vertebrae.  This  ligament  on  each  side  forms  the  outer  border  of 
Douglas's  pouch. 

Contained  in  the  broad  ligament  between  the  Fallopian  tube  and  ovary  can 
be  seen  the  remains  of  the  parovarium  or  organ  of  Rosenmiiller  (page  453)  and 
Gartner's  duct.  A  little  farther  in  are  the  remains  of  the  paroophoron  not  clearly- 
visible  to  the  unaided  eye. 

The  round  ligament  leaves  the  cornu  of  the  uterus  just  below  and  anterior  to 
the  Fallopian  tube,  and  passes  outward,  forward,  and  slightly  upward  to  reach  the 
internal  inguinal  ring  and  canal  through  which  it  passes  to  end  in  the  subcutaneous 
tissue  and  skin  of  the  labium  majus.  Owing  to  the  ovary  and  Fallopian  tube  falling 
backward  the  round  ligament  is  seen  as  a  distinct  cord  passing  to  the  sides  of  the 
pelvis.     It  receives  a  branch  from  the  deep  epigastric  artery. 

THE   OVARY. 

The  ovary  is  about  4  cm.  ( i  ^  in. )  long,  2  cm.  (fin.)  wide,  and  i  cm.  (|  in. )  thick. 
It  is  connected  with  the  posterior  surface  of  the  broad  ligament  by  a  very  short 
mesentery,  the  mesovarium.      It  is  through  this  that  the  ovarian  vessels  pass.      It  has 


Round  ligament 


Mesentery  or 
mesovarium 


Ovary 


Fimbriated  ex- 
tremity of  tube 


Ovarian  artery 
and  veins 


) 


Uterus,  fundus 


Fallopian  tube, 
isthmus 

Utero-ovarian 
ligament 

'Ampulla  of  tube 


Uterus,  body 

Cervix  of  uterus. 

Fig.  459. — The  uterus,  ovaries,  and  tubes. 


^—'Suspensory  ligament 

Infundibulum 
of  tube 


Broad  ligament 


two  ligaments,  one,  the  suspensory  or  infundibulopelvic  ligament,  is  a  fold  of  peri- 
toneum going  up  to  the  side  of  the  pelvis  above  and  contains  the  ovarian  vessels;  the 
other,  the  utero-ovarian  ligament,  going  in  the  broad  ligament  to  enter  the  uterus 
just  below  and  behind  the  Fallopian  tube.  The  ovary  lies  longitudinally  or  obliquely 
against  the  outer  wall  of  the  pelvis  with  the  ureter  just  behind  and  below  its  posterior 
edge.  From  its  upper  end  proceeds  the  suspensory  or  infundibulopelvic  ligament 
and  from  its  lower  end  the  utero-ovarian  ligament.  The  normal  Graafian  follicles  and 
corpus  luteum  should  not  be  mistaken  for  pathological  cysts.  The  Fallopian  tube 
surrounds  the  upper  end  of  the  ovary  and  its  fimbriated  extremity  clings  to  its 
surface  (Fig.  459). 

Fallopian  Tubes. — The  Fallopian  tube  is  about  11  cm.  (4^  in.)  long  and 
runs  in  the  broad  ligament  along  its  top  or  free  edge  from  the  uterus  to  the  ovary. 
Its  inner  portion  between  the  proximal  end  of  the  ovary  and  uterus  is  straight  and 
smaller  in  diameter  than  the  rest  and  is  called  the  isthnms.  Its  lumen  is  about  3  mm. 
{yi  in.).  The  part  beyond,  or  ampulla,  curves  around  the  ovary  from  above  down- 
ward and  is  larger  than  the  isthmus  and  has  a  lumen  of  about  8  mm.  {\  in.).  The 
size  of  the  abdominal  opening  of  the  Fallopian  tube  is  about  2  mm.  or  ^2^  in.  The 
part  of  the  broad  ligament  between  the  tube  and  mesovarium  is  called  the  mesosalpinx. 


THE    VAGINA. 


457 


THE  VAGINA. 

The  vagina  is  about  7. 5  cm.  (3  in. )  long;  its  posterior  wall  is  longer  than  the  ante- 
rior, being  8.75  cm.  (3)^  in.)  long.  It  will  thus  be  seen  that  if  the  uterus  is  slightly- 
depressed,  as  it  often  is,  the  cervix  is  within  easy  reach  of  the  examining  finger,  if,  how- 
ever, it  is  drawn  up,  as  by  an  abdominal  growth,  it  may  only  be  reached  with  difificulty. 
The  hollow  formed  by  the  anterior  wall  of  the  vagina  blending  with  the  anterior  lip  of 
the  cervix  is  called  the  anterior  fornix.  The  depression  behind  the  posterior  lip  is  the 
posterior  fornix,  behind  which  is  Douglas  s  pouch.  At  the  vulvar  outlet  the  lumen  of 
the  vagina  is  anteroposterior  in  direction,  it  then  changes  to  lateral  and  at  the  cervix 
becomes  round.  Its  walls  are  in  contact.  In  nulliparae  the  tube  is  more  uniform  in 
size,  but  in  multipane  it  is  small  at  each  end  but  large  in  the  middle.  It  is  much 
more  dilatable  and  larger  in  the  latter,  hence  operations  in  nulliparae  are  compara- 
tively rarely  done  through  the  vagina.  Anteriorly  the  vagina  in  its  upper  portion  is 
in  relation  with  the  bladder.     In  its  lower  portion  (about  one-third)  it  is  in  intimate 


Ovarian  artery 

Ureter 

Uterine  artery 
Cervix 

Vesical  artery 
Upper  end  of  vagina 

Bladder 


Fig.  460. — The  ureter,  ovarian  artery,  and  uterine  artery;  showing  their  relation  to  the  pelvic  organs. 


relation  with  the  urethra  except  at  the  upper  portion  of  the  latter.  Posteriorly  its 
upper  I  or  2  cm.  (3^  to  ^  in.)  is  in  front  of  the  peritoneum  and  Douglas's  pouch, 
below  this  lies  the  rectum,  and  between  it  and  the  surface  is  the  perineal  body. 
Laterally  the  ureters  are  close  to  the  vagina  and  about  half  way  up  they  empty  into 
the  bladder.  In  its  lower  portion  the  vagina  is  joined  by  the  insertion  of  the  levator 
ani  muscle.  The  connection  of  the  vagina  to  the  bladder  in  front  and  rectum  behind 
is  loose,  so  that  in  performing  operations  it  is  readily  separated  from  these  organs. 

The  Ureter  in  the  Female. — The  peKic  portion  of  the  ureter  in  the  female 
is  about  10  cm.  (4  in.  )  long.  It  crosses  the  pelvic  brim  at  a  level  with  the  first  piece 
of  the  sacrum  and  passes  over  either  the  common  iliac  artery  at  its  bifurcation  or  the 
external  iliac  at  its  commencement.  It  then  follows  the  wall  of  the  pelvis  downward, 
just  posterior  to  the  ovary  and,  near  the  floor  of  the  pelvis,  bends  forward  to  pass 
through  the  base  of  the  broad  ligament,  traversing  the  loose  connective  tissue  (para- 
metrium) and  being  about  1.5  to  2  cm.  (}4  to  ^  in.)  outside  of  the  cervix.     At  that 


458 


APPLIED   ANATOMY 


point  it  is  crossed  by  the  uterine  artery.  It  then  inchnes  somewhat  inward  and  forward 
along  the  sides  and  anterior  wall  of  the  vagina  to  enter  the  bladder.  Its  opening  in 
the  bladder  is  about  2.5  cm.  (i  in.)  below  the  level  of  the  external  os,  which  is  almost 
as  far  down  as  the  middle  of  the  anterior  vaginal  wall.  The  ureters  run  in  the  blad- 
der wall  obliquely  for  about  2  cm.  (^  in.)  and  their  openings  are  from  2.5  cm.  to  5 
cm.  (i  to2  in.)  apart  according  to  the  amount  of  vesical  distention  (Fig.  460). 

Blood- Vessels. — Tlie  main  blood-vessels  of  the  pelvic  genital  organs  are  the  ute- 
rine and  ovarian  arteries,  described  by  some  authors  as  the  single  utero-ovarian  artery. 

The  uterine  artery  comes  from  the  internal  iliac  and  passes  almost  horizontally 
inward  toward  the  lower  portion  of  the  cervix.  As  it  approaches  the  cervix  it  gives  off 
a  cervicovaginal  branch  passing  to  the  upper  part  of  the  vagina.  At  this  point  it  has 
just  crossed  in  front  of  the  ureter  and  is  about  level  with  the  external  os.  It  then  inclines 
upward,  reaching  the  side  of  the  uterus  at  its  junction  with  the  vagina.  It  passes  up  the 
side  of  the  uterus,  in  nulliparae  a  short  distance  away  from  its  side,  but  in  multiparae  close 
to  it,  until  it  reaches  the  cornu  above.      It  here  is  continuous  with  the  ovarian  artery. 

The  ovarian  artery  comes  down  from  the  aorta  as  does  the  spermatic  artery  in 


Iliac  node  of 
promontory 
group 


Fig.  461. — Lymphatics  of  uterus.     (Cuneo  and  Marcille.) 

the  male.  It  crosses  the  brim  of  the  pelvis  in  front  of  the  ureter,  enters  the  infundibulo- 
pelvic  or  suspensory  ligament  of  the  ovary  and  runs  horizontally  towards  the  uterus  in 
the  broad  ligament  between  the  round  ligament  and  the  ovary.  It  gives  branches  to  the 
ovary  and  tube  and  as  it  reaches  the  cornu  of  the  uterus  it  crosses  in  front  of  the  round 
ligament  and  joins  the  uterine  artery.  As  the  uterine  and  ovarian  arteries  are  continu- 
ous with  each  other  either  one  may  be  the  larger  and  they  vary  considerably  in  size. 

A  branch  of  the  deep  epigastric  artery  accompanies  the  round  ligament  inward 
and  anastomoses  with  the  uterine  and  ovarian  arteries.  It  may  be  enlarged  in  dis- 
ease of  the  ovaries  and  tubes. 

Lymphatics  (According  to  Poirier  and  Cuneo). — The  cervix  has  three  sets  of 
lymphatics.  The  first  passes  outward  and  upward  along  the  side  of  the  pelvis  ante- 
rior to  the  ureter  to  empty  into  the  nodes  along  the  external  iliac  artery.  The  second 
set  passes  backward  behind  the  ureter  to  empty  into  a  node  on  the  anterior  division 
of  the  internal  iliac  artery.  The  third  set  passes  from  the  posterior  surface  of  the 
cervix  almost  directly  backward  in  the  uterosacral  ligaments  to  empty,  some  into  the 
lateral  sacral  nodes  high  up  in  the  hollow  of  the  sacrum  and  some  into  the  nodes  of 
the  promontory  (Fig.  461). 


THE    FEMALE    PELVIC    ORGANS.  459 

The  i}mphatics  of  the  body  of  the  idejus  communicate  with  those  of  the  cervix 
below  and  at  the  cornu  pass  out  as  four  or  five  trunks  along  the  broad  ligament 
between  the  ovary  and  Fallopian  tube,  being  joined  by  branches  from  the  ovary. 
They  pass  through  the  infundibulopelvic  (suspensory)  ligament  and  follow  the  ovarian 
vessels  to  empty  into  the  aortic  nodes  below  the  kidney.  The  ovarian  lymphatics 
form  four  to  six  trunks  which  ascend  with  the  ovarian  vessels  to  end  in  the  lower 
aortic  nodes.  Opposite  the  fifth  lumbar  vertebra  they  communicate  with  the  trunks 
from  the  body  of  the  uterus. 

Pelvic  Examinations. — In  making  a  digital  examination  the  introduced  finger 
recognizes  that  in  the  nullipara  the  vagina  is  narrow,  admitting  only  one  finger, 
and  rugous  on  its  anterior  and  posterior  walls.  In  multiparae  it  is  smooth  and  admits 
two  fingers.  As  the  pulp  on  the  palmar  surface  of  the  finger  is  used  and  not  the  side, 
the  finger  is  to  be  directed  posteriorly  into  the  hollow  of  the  sacrum  and  then  brought 
anterior  (Fig.  462).  As  the  cervix  enters  the  anterior  wall  and  therefore,  if  normal, 
points  down  and  back,  and  is  about  6.5  to  7.5  cm.  (2^  to  3  in.  )  from  the  vulvar  orifice, 
it  is  usually  within  reach  of  the  tip  of  the  finger.  In  the  nullipara  it  is  felt  to  be  hard, 
rounded,  and  projecting  distinctly  into  the  vagina  with  a  small  os  In  multiparae  it 
is  larger,  softer,  not  so  prominent,  its  os  is  wider  and  often  irregular  in  shape  from 
lacerations.  The  uterus  is  often  displaced  so  that  the  os  may  look  forward  or  to  one 
side.  The  normal  uterus  is  not  firmly  fixed  but  is  movable  and  can  be  readily  moved 
up  and  down  by  the  examining  finger.     If  it  is  in  a  normal  anteverted  position  it 


Fig.  462. — Digital  vaginal  examination.     Ovary  slightly  prolapsed  but  as  yet  has  not  descended  entirely  into 

Douglas's  pouch. 

can  be  felt  between  the  finger  of  one  hand  within  and  firm  pressure  with  the  tips  of 
the  fingers  of  the  opposite  hand  from  without  just  above  the  symphysis  pubis.  When 
the  uterus  retains  its  normal  almost  straight  shape  and  falls  either  forward  or  back- 
ward it  is  said  to  be  in  a  position  of  anteversion  or  retroversion.  If  the  uterus  is  bent 
on  itself  in  the  shape  of  a  curve  it  is  then  said  to  be  anteflexed  or  retrofiexed.  In 
anteversion  the  external  os  points  down  and  back,  and  the  fundus  can  be  felt  with 
the  other  hand  above  the  pubes.  In  retroversion  the  os  looks  downward  and  for- 
ward and  the  body  of  the  uterus  cannot  readily  be  made  out  by  bimanual  palpation. 
If  anteflexed  instead  of  anteverted  it  is  more  diiftcult  to  feel  the  uterus  through  the 
abdominal  walls  but  its  fundus  can  be  felt  through  the  anterior  vaginal  wall  in 
front  of  the  anterior  lip  of  the  cervix.  If  retroflexed  its  projecting  rounded  fundus 
can  readily  be  felt  in  Douglas's  sac  just  behind  the  cervix.  By  a  digital  examina- 
tion one  determines  the  amount  of  mobility  of  the  uterus,  its  size,  its  position,  the  con- 
dition of  the  cervix,  whether  or  not  it  is  the  seat  of  indurations  such  as  occur  from 
cicatrices  and  cancer,  whether  it  is  lacerated,  etc.  Growths  like  fibroid  tumors 
projecting  from  the  anterior  or  posterior  walls  can  also  be  felt.  Particularly  in  thin 
subjects  relaxed  by  an2esthesia  the  broad  ligaments  can  be  followed  to  the  sides  and 
even  normal  ovaries  be  recognized.  When  prolapsed  they  fall  into  Douglas's 
pouch  and  can  be  felt  posterior  to  the  cervix.  Enlarged  Fallopian  tubes  can  be  feit 
as  distinct  masses  either  fixed  to  one  side  of  the  uterus  or  prolapsed  into  Douglas's 
pouch.  Renal  calculi  impacted  in  the  ureter  at  its  vesical  end  can  be  felt  between 
the  middle  and  upper  end  of  the  vagina  to  one  side  or  the  other. 


46o  APPLIED    ANATOMY. 

OPERATIONS  ON   THE   FEMALE   PELVIC  ORGANS. 

The  most  usual  operations  are  the  removal  of  the  uterus, — hysterectomy, — 
removal  of  the  ovary, — oophorectomy, — removal  of  the  Fallopian  tubes, — sal- 
pingectomy. The  ovaries  are  often  removed  with  the  diseased  tubes  and  also  in 
cases  of  hysterectomy.  These  operations  are  usually  done  through  an  abdominal 
incision  near  the  median  line  between  the  umbilicus  and  the  symphysis  pubis.  Not 
infrequently  they  are  done  through  the  vagina.  After  the  abdomen  is  opened  it  is 
important  to  be  able  to  recognize  and  isolate  the  individual  organs,  this  is  much  facil- 
itated by  elevating  the  pelvis  so  that  the  intestines  gravitate  toward  the  diaphragm 
— Trendelenburg's  position  (Fig.  463).  The  incision  having  been  made  and  the 
abdomen  opened  the  first  structure  seen  is  the  great  omentum.  This  often  extends  as 
low  as  the  symphysis.  As  it  hangs  from  the  transverse  colon  it  is  to  be  displaced 
upward  and  not  toward  the  sides.  The  next  structures  exposed  are  either  the  small 
or  large  intestines.  The  transverse  colon  normally  should  not  come  below  the  umbil- 
icus but  it  often  does  come  lower  and  may  even  descend  to  the  level  of  the  symphysis. 
When  it  is  low  it  lies  in  front  with  the  small  intestines  behind.  It  likewise  should  be 
displaced  upward.  Sometimes  the  sigmoid  colon  may  make  its  appearance  from  the 
ieit  and  more  rarely  the  caecum  from  the  right.      It  should  not  be  forgotten  that  both 


-Bladder 

Round  ligament  _  _      

^  ^  ^ -Uterus 

Fallopian  tube 


Broad  ligament 

Douglas's  pouch 

Ovary 

Fimbriated  extremity^^.^^;'''^  \ 'Xtx  iJ^^SS^  '1^^KU<^K  f  '"~^~~- Rectum 

of  Fallopian  tube 


Fig.  463. — View  of  the  interior  of  the  female  peivis  in  tne  Trendelenburg  position. 

these  structures  are  bound  to  the  posterior  abdominal  walls  and  may  often  be  covered 
in  front  by  coils  of  small  intestine.  Quite  frequently  however,  the  caecum  on  the 
right  and  iliac  colon  on  the  left  come  in  contact  with  the  anterior  abdominal  walls  in 
the  iliac  fossa  in  the  neighborhood  of  the  anterior  iliac  spines  and  may  extend  part 
way  down  Poupart's  ligament.  The  sigmoid  colon  if  distended  may  bulge  anteriorly 
but  more  usually  it  lies  posteriorly  covered  by  the  small  intestines.  If  it  or  the  caecum 
are  encountered  they  are  to  be  pushed  upward  and  to  the  side.  The  small  intestines 
are  to  be  displaced  upwards.  In  the  median  line  anteriorly  is  now  seen  the  bladder 
and  directly  behind  it  the  uterus.  If  the  uterus  is  drawn  to  one  side  the  broad  liga- 
ment of  the  opposite  side  is  made  tense  and  the  round  ligament  is  seen  running  to  the 
internal  ring  anteriorly  and,  more  posteriorly,  the  Fallopian  tube.  On  the  posterior 
surface  of  the  broad  ligament  below  the  outer  end  of  the  Fallopian  tube  is  seen  the 
ovary.  Farther  posteriorly,  in  the  hollow  of  the  sacrum,  is  the  rectum,  with  Doug- 
las's pouch  between  it  and  the  uterus  in  front.  If  it  is  desired  to  recognize  the 
structures  by  touch  instead  of  sight  then  the  anterior  abdominal  wall  is  followed 
down  over  the  bladder  and  the  fundus  of  the  uterus  recognized  as  a  hard  rounded 
mass.  This  can  be  grasped  between  the  thumb  and  fingers  and  followed  laterally 
past  the  cornu  to  the  broad  ligaments.  If  the  tubes  and  ovaries  are  enlarged  they 
may  be  found  lying  posterior  to  the  uterus  in  Douglas's  pouch  instead  of  laterally. 


THE   FEMALE    PELVIC   ORGANS. 


4bi 


Hysterectomy  (abdominal). — The  uterus  is  to  be  drawn  to  one  side  and  the 
posterior  portion  of  the  broad  hgament  is  grasped  out  toward  the  pelvic  wall.  As 
the  ovarian  artery  and  veins  run  along  the  top  of  the  broad  ligament,  a  ligature  is 
passed  through  it  below  them,  but  posterior  or  above  the  round  ligament.  A  clamp 
may  be  placed  on  the  side  toward  the  uterus  to  prevent  bleeding  from  the  other  side. 
The  ligament  is  then  divided  between  the  ligature  and  clamp  ;  sometimes  the  ovaries 
are  allowed  to  remain,  but  usually  they  are  removed  with  the  uterus.  A  liga- 
ture is  then  placed  around  the  round  ligament  and  it  is  divided  ;  often  the  round 
ligament  is  included  in  the  first  ligature.  The  incisions  in  the  broad  ligament  are 
then  carried  through  the  peritoneum  around  the  front  of  the  uterus  at  the  vesico- 
viterine  junction  and  also  posteriorly.  The  bladder  being  loosely  attached  can  be 
separated  by  blunt  dissection  down  to  the  level  of  the  external  os.  A  clamp  close 
to  the  side  of  the  cervix  controls  bleeding  from  the  sides  of  the  uterus,  and  by  push- 
ing away  the  connective  tissue  outwardly  the  uterine  artery  can  be  recognized, 
ligated,  and  divided.  The  ureter  lies  below  and  behind  i  to  2  cm.  (^4  to  ^  in.) 
distant  from  the  cervix.  The  cervix  is  then  detached  from  the  vagina,  and  the  bleed- 
ing from  the  small  vaginal  vessels  controlled  first  by  clamps  and  then  by  sutures. 


Body  of  uterus 


Cervix  uteri 


Vagina, 


Denuded  surface  of  bladder 

Fig.  464. — Removal  of  the  entire  uterus. 


Ovarian  artery 
Broad  ligament 
Round  ligament 

Uterine  artery- 
Bladder 


The  same  procedure  can  be  repeated  on  the  opposite  side  either  by  continuing  from 
below  up,  or,  as  before,  from  above  down  (Fig.  464). 

Oophorectomy. — In  removing  ovarian  tumors  any  adhesions  present  are  first 
loosened,  and  then  the  tumor  raised  up  and  its  pedicle  ligated.  The  Fallopian  tube 
is  usually  adherent  to  and  removed  along  with  the  tumor.  The  pedicle  is  formed  by 
the  utero-ovarian  ligament  on  the  inside  and  the  infundibulopelvic  on  the  outside  ; 
also  the  Fallopian  tube  and  part  of  the  broad  ligament  and  branches  or  trunks  of 
the  ovarian  artery  and  veins.  As  the  ovarian  vessels  run  horizontally,  if  the  ligature 
is  not  placed  low  they  may  not  be  included,  but  only  the  branches  which  come  off 
from  them  and  proceed  to  the  tumor. 

Salpingectomy. — In  removal  of  the  Fallopian  tubes  for  purulent  or  other  con- 
ditions, adhesions  are  frequently  encountered  owing  to  previous  inflammation.  To 
remove  such  a  tumor  it  is  better  usually  to  do  it  by  sight  rather  than  by  touch  alone. 
If  the  patient  is  placed  in  the  Trendelenburg  (elevated  pelvis)  posture  the  intestines 
fall  out  of  the  pelvis  and  are  kept  back  by  gauze  pads.  Any  coils  which  are  stuck 
fast  to  the  adjacent  organs  can  then  be  carefully  dissected  and  peeled  loose  and 
the  tumor  exposed.  It  will  be  found  either  posteriorly  in  Douglas's  pouch,  or 
laterally  between  the  uterus  and  side  of  the  pelvis,  pushing  the  former  toward  the 
opposite  side.  The  distended,  enlarged  tube  with  the  ovary  adherent  to  it  can 
then  be  isolated  by  inserting  the  finger  between  it  and  the  pelvic  wall,  beginning  at 
the  posterior  edge  of  the  broad  ligament  and  following  it  around  posteriorly,  loos- 
ening it  from  the  rectum  and  Douglas's  pouch  until  the  uterus  is  reached.     The 


462  APPLIED    ANATOMY. 

finger  is  then  passed  beneath  the  tumor  and  it  is  peeled  off  the  pelvic  floor,  it  can 
then  be  raised  up  and  its  base  ligated  much  like  the  pedicle  of  an  ovarian  tumor. 
If  this  is  carefully  done  the  parietal  peritoneum  will  not  be  broken  through  and  there 
will  be  little  or  no  bleeding. 

Tumors  of  the  Broad  Ligament  (intraligamentary  tumors). — Certain  tumors 
originating  either  from  the  structures  of  the  broad  ligament  or  ovary,  c-  side  of  the 
uterus,  grow  between  the  layers  of  the  broad  ligament.  Parovarian  cysts  arising 
from  the  remains  of  the  Wolffian  body  are  of  this  character.  These  intraligamentary 
cysts  are  retroperitoneal.  The  Fallopian  tube  is  spread  over  and  adherent  to  their 
upper  surface.  As  they  grow  down  they  come  in  contact  with  the  ureter,  which 
becomes  adherent  to  the  bottom  and  sides  of  the  growth.  The  liability  of  injury  to 
the  ureter  is  the  greatest  danger  in  these  cases,  and  can  only  be  escaped  by  search- 
ing for,  recognizing,  and  avoiding  it.  These  growths  are  exposed  by  splitting  the 
peritoneum  covering  them  and  then  shelling  them  out.  At  times  they  are  large 
and  formidable  and  extremely  difficult  to  remove. 

Extra-Uterine  Pregnancy. — The  most  dangerous  factor  in  operating  for 
extra-uterine  pregnancy  is  hemorrhage.  The  tumor  is  usually  tubal  in  position.  The 
bleeding  comes  from  the  sac,  therefore  loosening  and  isolating  it  should  be  done  with 
the  greatest  care  to  avoid  rupturing  it.  If  already  ruptured  the  blood  is  to  be 
rapidly  sponged  out,  the  uterus  recognized  and  grasped  with  the  hand,  which  is 
then  slid  outward  until  the  ruptured  tumor  is  felt  and  drawn  up.  The  blood  comes 
to  the  tumor  from  the  ovarian  artery  and  uterine  artery.  To  control  the  former  a 
clamp  is  placed  on  the  broad  ligament  close  to  the  pelvic  wall.  To  control  the 
latter  a  clamp  is  placed  low  down  on  the  broad  ligament  close  to  the  uterus.  The 
active  bleeding  then  ceases. 

Vaginal  Hysterectomy. — The  uterus  if  not  much  enlarged  can  be  removed 
through  the  vagina  when,  as  is  the  case  in  multiparae,  it  is  lax  and  capacious. 

The  cervix  is  grasped  and  drawn  down  to  the  vulva  and  the  mucous  membrane 
incised  in  the  anterior  fornix  and  posteriorly  close  to  the  uterine  tissue.  The  bladder 
is  pushed  up  and  separated  from  the  cervix  by  dry  dissection  with  occasional  snip- 
ping of  fibrous  bands  by  scissors  until  the  peritoneum  at  the  level  of  the  internal  os 
is  reached.  The  peritoneum,  which  from  this  point  up  is  adherent  to  the  uterus,  is 
opened  and  divided  to  the  broad  ligaments  on  each  side.  Douglas's  sac  is  next 
opened  posterior  to  the  cervix  and  close  to  it,  and  the  opening  enlarged  with  the 
finger  to  the  broad  ligaments.  A  clamp  is  now  placed  on  each  broad  ligament  low 
down  to  control  the  uterine  arteries.  By  hooking  the  finger  above  the  fundus  it  can 
be  brought  back  and  down  and  out,  the  ovaries  usually  coming  with  it.  The  re- 
maining portion  of  the  broad  ligaments  is  then  either  clamped  or  tied  to  control  the 
ovarian  arteries.  Some  operators  use  clamps  alone,  others  use  ligatures.  Vaginal 
branches  which  bleed  are  grasped  with  haemostats  and  ligated.  The  ureters,  which 
lie  1.5  to  2  cm.  (j4  to  ^  in.)  away  from  the  cervix,  are  pushed  outward  when  the 
opening  in  Douglas's  sac  is  enlarged,  and  will  be  avoided  by  not  placing  the  clamps 
too  far  away  from  the  cervix. 

Laceration  of  the  Cervix. — The  cervix  is  made  accessible  for  operation  by 
grasping  it  with  tenaculum  forceps  and  drawing  it  down  to  the  vulva.  It  is  there 
held  to  one  side,  which  renders  the  laceration  easily  accessible  for  excision  and  the 
introduction  of  sutures.      Bleeding  is  controlled  by  the  sutures. 

THE  FEMALE  EXTERNAL  GENITALS. 

The  /adia  majora  meet  anteriorly  in  the  anterior  commissure  and  posteriorly  in 
the  posterior  commissure. 

The  space  between  the  posterior  commissure  and  the  anus,  about  3  cm.  (i^ 
in.)  is  the  perineum  (Fig.  465). 

The  labia  minora  divide  anteriorly  to  form  the  prepuce  above  the  clitoris  and 
the  frcenum  on  its  lower  surface.  Posteriorly  they  fade  away  into  a  thin  crescentic 
fold  of  mucous  membrane  called  thefourchette.  The  space  between  the  labia  minora 
is  the  vestibule.  The  meatus  or  urethra  is  in  the  vestibule  2. 5  cm.  ( i  in. )  behind 
the  clitoris.     It  is  surrounded  by  a  ring  of  mucous  membrane  and  in  introducing  the 


THE    FEMALE    EXTERNAL   GENITALS. 


463 


catheter  it  can  be  recognized  by  the  sense  of  touch  and  so  localized.  The  openings  of 
Xhe.  para- urethra/  duds  are  just  below  and  to  the  outside  of  the  meatus.  The  vulvo- 
vaginal glands  (of  Bartholin)  empty  on  the  inner  side  of  the  labia  minora  in  the 
sulcus  between  them  and  the  hymen.  The  openings  of  the  ducts  are  just  visible  to 
the  naked  eye.      Tiie  openings  are  about  opposite  the  middle  of  the  vaginal  orifice 


Prepuce  of  clitoris 

Fraenum 

Vestibule 

Urethra 

Hymen 

Fossa  navicularis 


-Clitoris 


— Labium  majus 
Para-urethral  duct 
Labium  minus 
Vulvovaginal  gland 

Fourchette 
Posterior  commissure 


*«- 


Fig.  465. — External  female  genitals  (vulva). 

and  the  ducts  pass  down  and  out  to  the  glands,  which  are  of  the  size  of  a  bean  and  lie 
on  each  side  of  the  lower  end  of  the  vagina. 

The  hyfneti   partly  occludes  the  lower  end  of  the  vagina  across  its  posterior 
portion.    The  carunadce  hymenales  are  the  remains  of  the  ruptured  hymen.     'Y\^^  fossa 
■navicularis  is  the  space  between 
the  hymen  and  the  fourchette. 

Clinical  Considerations. 
—The  external  genitals  are  well 
supplied  with  veins,  and  in  preg- 
nancy or  pelvic  growths  they  may 
become  enlarged  and  varicose, 
especially  over  the  labia  majora. 
The  fourchette  and  perineum  fre- 
quently become  ruptured  in  deliv- 
ery, the  tear,  if  complete,  going 
into  the  rectum.  The  meatus  is 
sometimes  the  seat  of  a  papillo-an- 
giomatous  growth  called  urethral 
caruncle.  It  is  treated  by  removal. 
The  vulvovaginal  glands  are  the 
seat  of  cysts  and  abscesses.  They 
appear  as  swellings  alongside  the 
posterior  portion  of  the  vaginal 
opening.  The  former  are  to  be  carefully  and  completely  excised  and  the  latter  opened 
and  packed.  The  vulvar  slit  is  anteroposterior,  the  vagina  forms  a  transverse  slit 
and  the  hymen  is  placed  at  the  point  of  transition.  In  making  a  vaginal  examination 
(dorsal  decubitus)  the  index  finger  is  to  be  held  vertically  until  the  vestibule  is 
entered.      It  then  is  passed  horizontally  into  the  vagina  and  turned  palmar  surface 


Cystocele 


Rectocele 


Fig.  466. 


Hernia  of  the  blnrider  (cystocele)  and  of  the  recturh 
(rectocele). 


464 


APPLIED    ANATOMY. 


upward  to  recognize  the  cervix  entering  the  anterior  vaginal  wall.  Firm  pressure 
with  the  other  hand  to  depress  the  external  parts  is  necessary  to  reach  the  posterior 
fornix  and  Douglas's  pouch. 

Cystocele. — As  a  result  of  the  relaxation  following  childbirth  the  bladder  may 
prolapse  through  the  vaginal  orifice.  When  the  uterus  prolapses  it  also  drags  the 
bladder  down  with  it.  It  is  to  be  recognized  by  passing  a  sound  through  the  urethra 
into  it.  It  is  treated  by  excising  the  mucous  membrane  covering  the  cystocele  and 
sewing  the  sides  of  the  wound  together,  thus  crowding  the  mucous  lining  of  the 
bladder  up  into  position  (Fig.  466). 

Rectocele. — The  rectum  prolapses  at  the  posterior  wall  of  the  vagina  the  same 
as  the  bladder  does  anteriorly  and  it  is  treated  in  a  similar  manner. 

THE   FEMALE   PERINEUM. 

The  perineum  in  the  female  is  much  like  that  of  the  male.  It  has  a  central  point 
at  which  converge  the  external  sphincter  ani  from  behind,  the  superficial  transverse 


Bulbocavernosus. 
(sphincter  vaginae) 


Tuber  ischii 


Levator  ani  muscle 


Ischiocavernosus 
muscle 


Triangular  ligament 


Superficial  trans, 
perineal  muscle 


Central  point  of 
perineum 


^White  line 
^Sphincter  ani 


Fig.  467. — Female  perineum. 

perinei  muscles  from  each  side  and  the  bulbocavernosus  muscles  from  the  front.  The 
ischiocavernosus  muscles  lie  along  the  rami  of  the  pubes.  These  superficial  muscles 
are  reinforced  by  the  deep  transverse  perinei  muscle,  which  comes  from  the  ramus 
of  the  ischium  on  the  side  to  insert  by  its  anterior  fibres  around  the  urethra  (com- 
pressor urethrae),  its  middle  fibres  into  the  vaginal  wall,  and  its  posterior  fibres  at 
the  central  point  of  the  perineum.  Also  the  levator  ani  muscle  inserts  into  the  lower 
end  of  the  vagina  anteriorly,  then  into  the  central  point  of  the  perineum,  next  into 
the  lower  end  of  the  rectum,  and  finally  into  the  coccyx.  The  deep  layer  of  the 
superficial  fascia  (CoUes's  fascia)  and  the  triangular  ligament  being  pierced  by  the 
vagina  are  not  so  marked  as  in  the  male — between  them  lie  the  ischiocavernosus, 
bulbocavernosus,  and  superficial  transverse  perinei  muscles  (Fig.  467). 

Rupture  or  Laceration  of  the  Perineum. — When  the  tear  goes  only  part 
way  through  the  perineum  it  is  called  an  incomplete  laceration;  when  it  goes  through 
into  the  rectum  it  is  a  complete  tear. 

In  an  incomplete  tear  the  bulbocavernosus  muscles  (called  also  sphincter 
vaginae)  are  separated  behind  and  consequently  their  function  of  holding  the  labia 
majora  together  is  lost  and  the  vulva  gapes.      In  a  complete  tear  all  the  muscles 


THE    MALE    EXTERNAL    GENITALS. 


46s 


/ 


helping  to  form  the  perineum  are  divided:  they  are  the  bulbocavernosus,  the  super- 
ficial and  deep  transverse  perinei,  and  the  levator  ani  and  external  sphincter  ani 
muscles.  They  draw  the  sides  of  the  wound  apart,  sometimes  forming  a  dimple  on 
each  side,  and  thus  enlarge  the  vaginal  outlet  and  allow  the  anterior  wall  of  the  rectum 
as  well  as  the  posterior  wall  of  the  bladder 
to  prolapse  (Fig.  468). 

Operation. — The  torn  area  is  to  be 
denuded  by  beginning  the  incision  not 
higher  up  than  the  lower  end  of  the  labium 
minus  on  one  side  and  carrying  it  down 
and  then  up  to  a  corresponding  point  on 
the  opposite  side.  From  the  extremities 
of  this  incision  two  more  are  made  ex- 
tending 2.5  to  5  cm.  (i  to  2  in.)  up  the 
vagina  and  meeting  in  the  median  line. 
Emmet  carried  the  denudation  up  each 
lateral  sulcus.  The  mucous  membrane  so 
marked  out  is  then  dissected  away ;  to  close 
the  wound  some  operators  introduce  and 
bring  out  the  stitches  all  on  the  skin  surface, 
while  others  introduce  and  tie  half  of  them 
on  the  vaginal  surface  and  the  other  half  on 
the  skin  surface.  The  needle  is  to  be  car- 
ried well  out  toward  the  rami  of  the  ischium 
so  as  to  include  a  large  mass  of  tissue. 

If  the  mucous  membrane  of  the  rectum  has  been  torn  it  is  to  be  sewed  together 
before  the  perineal  tissues  are  approximated. 


Fig.  468. — Rupture  of  the  perineum.  The  vulva 
gapes,  showing  the  rectum  bulging  forward;  the  two 
dimples,  one  on  each  side  of  the  anus,  are  caused  by 
the  retracted  muscles. 


THE  MALE  EXTERNAL  GENITALS. 

Penis. — The  penis  is  composed  of  the  two  coj-pora  cavernosa  attached  poste- 
riorly to  the  rami  of  the  ischia  and  pubes  and  terminating  in  blunt  ends  anteriorly, 
and  the  corpus  spo7igios2im,  commencing  at  the  bulb,  at  the  central  point  of  the 
perineum  posteriorly,  and  ending  in  the  glans  anteriorly.  The  glacis  is  the  extended 
corpus  spongiosum  and  covers  the  ends  of  the  corpora  cavernosa.      Its  extended  rim 


Prepuce  ■ 

Glans- 

Meatus- 
Fossa  navicularis' 


Fibrous  sheath 
Collum  glandis  / 

Corona  glandis     /  /^ 


Dorsal  vein 

Corpora  cavernosa 


i:,...*?«gifP| 


^■'iSU'^a^TrTT^ 


Corpus  spongiosum 
Fig.  469. — Structure  of  the  penis. 


is  called  the  corona  glandis  and  the  groove  immediately  behind,  the  neck,  or  col- 
hmi  glandis.  In  the  centre  of  each  corporus  cavernosum  runs  an  artery  (Fig.  469). 
The  skin  is  thin,  loose,  free  from  hair  except  at  the  root,  and  has  beneath  it 
some  fibres  of  the  dartos.  It  projects  over  the  glans,  forming  the  prepuce  and  is 
attached  at  the  neck  or  collum  glandis  and  underneath  as  far  forward  as  the  urethra, 
forming  thefrcsnum.  The  connective  tissue  beneath  the  skin  is  loose  and  free  from 
fat.  A  fibrous  sheath  (Buck's  fascia)  surrounds  the  corpora  cavernosa  and  corpus 
spongiosum  and  binds  the  three  together.  It  is  continuous  posteriorly  with  the  sus- 
pensory ligament  and  the  deep  layer  of  the  superficial  fascia  (Colles's  fascia). 
30 


406  APPLIED    ANATOMY. 

Anteriorly  it  ends  at  the  collum  glandis.  The  corpora  cavernosa  and  corpus  spongi- 
osum have  each  a  separate  fibrous  sheath  which  separates  the  two  corpora  cavernosa 
forming  the  septum  pcctmifoi^mc:  it  is  incomplete  anteriorly,  allowing  the  blood  of 
the  two  corpora  cavernosa  to  mingle.  The  separate  sheath  of  the  corpus  spongi- 
osum is  not  as  marked  as  those  of  the  corpora  cavernosa.  The  single  dorsal  vein  of 
the  penis  runs  in  the  median  line  with  an  artery  to  each  side  and  the  dorsal  nerves 
still  farther  out.  They  all  lie  between  the  fascial  covering  of  the  corpora  cavernosa 
beneath  and  the  fibrous  sheath  above. 

The  lymphatics  of  the  prepuce  and  skin  drain  into  the  inguinal  nodes,  those 
of  the  glans  empty  into  the  nodes  in  and  just  above  (inside  the  abdomen)  the  crural 
canal;  one  radicle  enters  through  the  inguinal  canal  running  posterior  to  the  cord. 
As  the  lymphatic  radicles  anastomose  at  the  root  of  the  penis  a  lesion  on  one  side  of 
the  organ  may  involve  the  lymphatic  nodes  in  the  opposite  inguinal  region. 

Practical  Considerations. — The  opening  of  the  prepuce  is  often  constricted, 
so  that  the  glans  cannot  be  uncovered.  This  condition  is  called ////wc'^-z'^.  A  certain 
amount  is  normal  in  young  children.  At  times  the  prepuce  becomes  adherent  to  the 
glans  but  it  can  usually  be  separated  by  a  blunt  instrument  without  cutting.  When 
the  sulcus  is  reached  an  accumulation  of  smegma  is  seen.  This  is  produced  by  the 
subaceous  glands  of  the  corona  and  collum  glandis  and  under  surface  of  the  prepuce. 
In  performing  ciraimcision  the  prepuce  should  not  be  drawn  too  far  forward  or  too 
much  of  the  skin  and  not  enough  of  the  mucous  surface  will  be  removed;  a  common 

mistake.  It  is  sulificient  to  remove  the  skin 
and  mucous  membrane  two-thirds  of  the 
—  way  back  to  the  sulcus  and  then  bring  the 
ends  of  the  incision  gradually  down  and  for- 
ward to  meet  at  the  lower  angle  of  the  meatus 
(Fig.  470).  By  doing  this  the  fraenum  is  not 
cut  and  troublesome  bleeding  from  the  little 
artery  it  contains  is  avoided.  The  laxity 
of  the  skin,  especially  of  the  prepuce,  favors 
rapid  swelling.  When  a  contracted  prepuce 
Fig.  470.— Circumcision.  is  forcibly  drawn  behind  the  glans  it  con- 

stricts the  veins  and  the  part  beyond  the 
constriction  swells  rapidly.  This  is  called  paraphimosis.  To  relieve  it  an  incision  is 
made  through  the  skin  directly  across  the  constricting  band  and  the  prepuce  can 
then  be  pulled  forward  over  the  glans. 

Extravasation  of  urine  may  invade  the  penis  beneath  the  fibrous  sheath  but  does 
not  invade  the  glans  because  the  sheath  stops  at  the  collum  glandis. 

Fracture  or  rupture  of  the  corpora  cavernosa  may  occur  from  violence.  The  extrav- 
asated  blood  is  absorbed  and  the  laceration  heals  with  a  scar.  In  erection  this  part  does 
not  expand,  hence  deformity  and  distortion  with  interference  of  function  may  result. 
Chordee. — When  the  urethra  is  inflamed  the  exudate  may  involve  the  corpus 
spongiosum  surrounding  it  and  prevent  it  from  expanding.  In  erection  the  organ 
assumes  a  downward  curve,  a  condition  designated  as  chordee.  It  disappears  with 
the  subsidence  of  the  inflammation. 

Amputation  of  the  Penis. — The  penis  is  frequently  amputated  for  carcinoma, 
which  disease  is  favored  in  the  aged  by  the  irritation  resulting  from  a  long-existing 
phimosis.  In  operating  two  things  are  to  be  guarded  against,  bleeding  and  subsequent 
contraction  of  the  meatus.  Bleeding  may  come  from  the  dorsal  arteries  or  the  artery 
which  runs  in  the  middle  of  each  corpus  cavernosum.  They  can  first  be  controlled  by 
a  circular  rubber  band  and  then  later  readily  ligated.  To  prevent  contraction  of  the 
new  meatus  three  methods  are  available:  (i)  A  long  dorsal  and  short  under  flap  may 
be  cut  and  the  urethra  dissected  out  from  the  under  flap  and  allowed  to  project  beyond 
the  cut  corpora  cavernosa.  The  long  dorsal  flap  is  brought  down,  pierced,  and  the 
urethra  drawn  through.  It  is  then  slit  up  and  sewed  on  each  side.  A  few  sutures 
are  then  used  to  unite  the  upper  and  lower  flaps  below  the  urethra.  (2)  Two  lateral 
flaps  may  be  made  and  the  split  urethra  sewed  in  the  line  of  union  between  the  two 
flaps.  (3)  (Writer's,  University  Medical  Magazine,  January,  1897.)  A  circular  cut 
is  made  around  the  penis  and  the  skin  turned  back.     The  penis  is  then  turned  up, 


THE    MALE    EXTERNAL    GENITALS. 


467 


the  urethra  dissected  out  for  1.25  cm.  (y^  in.),  aud  the  corpora  cavernosa  divided. 
The  arteries  being  tied,  the  two  outer  edges  of  the  corpora  cavernosa  are  brought 
together  in  the  median  Hne  with  three  catgut  sutures.  The  urethra  is  then  sht  up  in 
three  places,  one  below  and  two  above;  the  three  square  flaps  so  formed  are  then 
turned  back  and  their  corners  cut  off.  This  makes  three  small  triangular  flaps  which 
when  spread  out  form  one  large  triangle.  The  skin  is 
then  sutured  accurately  to  the  edges  of  this  triangle  and 
no  raw  surface  is  left  (Fig.  471). 

Scrotum,   Testicles,  and  Spermatic    Cord. — 
The  SCROTUM  is  the  bag  in  which  the  testicles  are  con- 
tained.      It  consists  of  skin  and  dartos.     The  remaining 
tissues  covering  the  testicles  are  derived  from  the  layers 
of  the  abdominal  wall    and    belong    properly  to   them. 
The  s^in  is  thin,  loose,  wrinkled,  and  contains  sebaceous 
glands  which  frequently  become  occluded,  forming  small 
tense  cystic  tumors.      The  dartos  is  composed  of  loose 
connective  tissue  and  unstriped  muscular  fibres.     It  is  in- 
timately connected  with  the  skin  but  moves  freely  on  the   sewed  ^o  the  !ii<in  to"avold  cTcatrTcai 
parts  beneath.    It  is  continuous  with  the  general  superficial   *=°"*^*'="°"-    (Author's  method.) 
fascia  and  with  its  deep  layer  or  Scarpa's  fascia  of  the  abdomen  and  Colles' s  fascia  of  the 
perineum.      It  dips  between  the  testicles,  forming  an  incomplete  septum  (Fig.  472). 

Practical  Applications. — Contraction  of  the  dartos  wrinkles    the  scrotum   and 
if  wounded  the  edges  are  inverted.     For  this  reason,  in  operations  on  the  scrotum. 


Fig.  471.— Amputation  of  the 
penis.  Mucous  membrane  of  urethra 
everted,  cut  in  triangular  form  and 


Cremasteric  fibres 


Spermatic  artery 
Pampiniform  plexus  of  veins 

Deferential  artery 

Vas  deferens 

Skin 

Globus  major  epididymis 

Digital  fossa 
Hydatid  of  Morgagni 
Dartos 

Tunica  vaginalis 


Septum 


Fkj.  472. — Scrotum,  testicles,  and  sp)ennatic  cord. 

if  primary  union  is  desired  particular  care  must  be  taken  to  approximate  accurately 
the  skin  edges  and  prevent  their  inversion.  The  raising  of  the  testicles  is  done  by  the 
cremaster  muscle  and  not  by  the  dartos  except  incidentally  as  the  scrotum  contracts. 
The  scrotum  is  supplied  by  blood  through  the  perineal  branches  of  the  internal 
pudic  artery,  and  by  the  external  pudic.  On  account  of  the  looseness  of  the  skin 
attachment,  oedema  and  extravasation  of  blood  and  urine  may  be  very  extensive  and 
violent.     They  readily  impair  the  blood  circulation  and  gangrene  not  infrequently 


468  ■'^^m:  APPLIED    ANATOMY. 

results.  It  is  for  this  reason  that  urinary  infiltrations  are  to  be  at  once  incised,  and 
in  operations  the  greatest  care  is  exercised  to  stop  every  bleeding  vessel.  Infec- 
tion of  this  region  is  particularly  troublesome  and  a  strict  technic  is  necessary  in 
operating  to  avoid  it.  In  some  cases  of  varicocele  with  pendulous  scrotum  a  portion 
of  the  scrotum  is  excised  in  order  to  support  the  testicles. 

Testicles. — The  testicles  begin  to  develop  early  in  fetal  life — about  the  third 
month — below  and  in  front  of  the  kidneys,  opposite  the  second  lumbar  vertebra. 

Descent  of  the  Testes. — The  testis  is  covered  by  peritoneum,  which  is  prolonged 
at  its  upper  and  lower  ends.  The  lower  reaches  down  to  the  internal  ring  and  later 
contains  fibrous  and  muscular  tissue  and  passes  through  the  inguinal  canal  to  the 
lower  part  of  the  scrotum:  it  is  called  the  gubemiacuhim  testis.  It  reaches  its  highest 
development  in  the  sixth  month  and  its  remains  attach  the  testicle  to  the  lower  part 
of  the  scrotum  as  the  ligament  of  the  scrotum.  As  the  testicle  descends,  the  upper 
peritoneal  band  covers  the  spermatic  vessels  from  the  region  of  the  kidney  down. 
The  lower  portion  of  the  gubernaculum  sends  branches  to  the  regions  of  the  pubes, 
perineum,  and  saphenous  opening.  The  testicle  is  preceded  in  its  descent  through 
the  inguinal  canal  by  a  fold  of  peritoneum — the  vaginal  process — which  forms  the 
tunica  vaginalis  over  the  testicle,  the  part  above  atrophying. 

Practical  Applications.  — The  testicle  may  be  arrested  in  some  portion  of  its 
course,  forming  an  undescended  testicle,  or  it  may  be  displaced,  as  has  been  suggested, 
by  an  abnormal  development  of  one  of  the  subsidiary  bands  of  the  gubernaculum. 
Hence  it  may  be  found,  not  in  the  scrotum,  but  in  the  perineum,  in  the  femoral 
region,  or  in  the  pubic  region.  It  may  go  through  the  femoral  canal  instead  of  the 
inguinal.  If  it  is  undescended  it  may  be  arrested  in  the  abdominal  cavity,  in  the 
inguinal  canal,  or  at  the  external  ring. 

The  vaginal  process  may  not  entirely  close,  so  that  the  peritoneal  fluid  passes 
down  to  the  tunica  vaginalis  covering  the  testicle;  this  is  called  a  congenital  hydrocele. 
If  the  opening  is  large  enough  for  intestine  to  enter,  it  forms  a  congenital  hernia 
(see  page  383).  If  the  opening  is  closed  above,  usually  at  the  external  ring,  and 
fluid  accumulates  in  the  tunica  vaginalis  it  forms  an  infantile  hydrocele.  If  a  portion 
of  the  vaginal  process  persists  somewhere  along  the  spermatic  cord  between  the 
internal  ring  and  top  of  the  testis  it  forms  a  cyst  and  is  called  an  encysted  hydrocele 
of  the  cord.  The  vaginal  process  closes  at  its  upper  portion  just  before  birth  and  in 
those  cases  which  are  patulous  after  birth  (congenital  hernia  and  hydrocele)  there 
is  a  tendency  to  spontaneous  closure,  hence  operative  measures  are  usually  deferred. 
The  vaginal  process  also  descends  into  the  inguinal  canal  in  the  female  and  a  hydro- 
cele of  it  is  called  a  hydrocele  of  the  canal  of  Nuck. 

Size,  Position,  etc. — The  normal  testicles  are  4  cm.  {lyi  in.)  long,  2.5  cm. 
(i  in.)  wide,  and  2  cm.  (f  in.)  thick.  They  are  firm  to  the  touch.  If  larger  they 
are  either  hypertrophied  or  diseased.  If  hypertrophied  their  consistence  is  not  ma- 
terially altered,  if  diseased  they  are  usually  harder.  If  smaller  they  are  usually 
atrophied  and  besides  the  lessening  of  size  are  also  softer  and  flabby  in  consistency. 

They  lie  attached  at  the  inner  posterior  portion  of  the  scrotum  and  their  long 
axis  points  upward,  slightly  forward,  and  outward.  In  all  cases  of  hernia  and  hydro- 
cele the  testicle  is  to  be  felt  for  at  the  inner  posterior  aspect  of  the  swelling.  In 
rare  instances  the  testicle  is  placed  anteriorly  instead  of  posteriorly  and  is  Hable  to 
be  wounded  in  introducing  a  trocar  into  the  tunica  vaginalis  to  empty  a  hydrocele. 
To  avoid  this  accident  the  position  of  the  testicle  can  be  determined  not  only  by 
touch  but  also  by  seeing  the  outline  of  the  testicle  by  means  of  a  light  placed  on  the 
opposite  side  of  the  scrotum.  As  the  testicle  is  almost  always  low  down  the  puncture 
should  be  made  higher  up  and  preferably  on  the  outer  side. 

Epididymis. — The  vas  deferens  descends  to  the  lower  end  of  the  testicle  and 
becoming  much  convoluted  forms  the  globus  minor  or  tail,  thence  ascends,  forming 
the  body,  and  finally  at  the  top,  receiving  the  efferent  ducts,  forms  the  globus  major 
or  head.  Between  the  body  of  the  epididymis  and  testis  is  a  pocket  or  depression 
called  the  digital  fossa.  Attached  to  the  upper  end  of  the  testis  is  a  small  flat  body 
in  front  of  the  globus  major  and  attached  to  the  globus  major  itself  is  a  small  cystic 
pedunculated  growth.  Both  are  known  as  the  hydatids  of  Morgagni,  and  the  former  is 
the  remains  of  the  duct  of  MUller,  while  the  latter  is  derived  from  the  Wolffian  body. 


THE   MALE  EXTERNAL  GENITALS.  469 

Practical  Application. — Inflammation  of  the  testis  proper  is  called  orchitis;  of 
the  epididymis,  epididymitis.  When  the  testicle  as  a  whole  is  enlarged,  if  it  is  due 
to  syphilis  or  new  growth,  the  testis  itself  is  mainly  affected  and  it  is  then  called 
sarcocele.  Inflammations,  the  result  of  injury,  may  produce  a  true  orchitis,  but  when 
arising  from  infections  they  involve  the  vas  deferens  and  epididymis  and  produce 
an  epididymitis.  This  is  the  case  in  gonorrhoea  and  tubercle,  and  to  a  less  extent  in 
mumps.  An  enlarged  epididymis  can  be  outlined  by  careful  palpation  as  being  dis- 
tinct from  the  testis  proper.      Advanced  tubercle  may  invade  the  testis  subsequently. 

Cystic  disease  is  fairly  frequent ;  it  involves  the  epididymis,  especially  the  globus 
major.  The  cysts  may  be  very  numerous  and  may  spring  either  from  the  ducts  of 
the  globus  major  or  from  the  hydatids  of  Morgagni. 

Coverings  of  the  Testicle.  — The  tunica  vaginalis  comes  from  the  peritoneum, 
the  tunica  albuginea  is  the  continuation  of  the  transversalis  fascia  (infundibuliform 
fascia);  it  is  strong,  dense,  and  inelastic.  Over  this  are  a  few  cremasteric  fibres  from 
the  internal  oblique  and  the  intercolumnar  fascia  from  the  external  oblique.  The 
dartos  is  continuous  with  the  fascia  of  Scarpa  of  the  abdomen. 

Application. — The  tunica  vaginalis  being  a  closed  sac  may  become  distended  with 
serum,  forming  a  hydrocele.  The  precautions  to  be  taken  in  tapping  it  have  been 
alluded  to  above.  It  is  treated  radically  by  excising  the  parietal  layer  and  leaving  the 
visceral  layer  covering  the  testicle  and  epididymis.  The  questions  of  hemorrhage  and 
skin  inversion  have  also  been  discussed.  Inflammation  causes  intense  pain  on  account 
of  the  unyielding  character  of  the  tunica  albuginea.  To  relieve  it  multiple  fine  punc- 
tures are  sometimes  made.  Abscess  (tuberculous)  of  the  testicle  opens  the  tunica  albu- 
ginea and  the  testicular  tissue  protrudes,  forming  a  hernia  testis.  Such  testicles  are 
often  excised,  but  if  not  the  hernia  eventually  shrinks  and  reduces  itself  (Holden). 

Spermatic  Cord. — The  left  spermatic  cord  is  longer  than  the  right,  hence  the 
left  testicle  hangs  lower.  The  cord  is  composed  of  the  vas  deferens  with  its  artery,  a 
branch  of  the  superior  vesical,  and  veins;  the  spermatic  artery  with  its  veins;  the 
cremasteric  artery;  and  the  layers  derived  from  the  abdominal  wall  (the  same  as  pos- 
sessed by  the  testicle).  It  also  possesses  nerves,  the  genital  branch  of  the  genitocrural, 
and  branches  of  the  sympathetic,  and  lymphatics.  The  vas  deferens  is  a  small,  round, 
hard  cord  lying  posteriorly.  It  can  be  seen  when  the  elements  of  the  cord  are  sep- 
arated and  can  be  distinctly  felt  even  through  the  scrotum.  The  deferential  artery 
accompanies  and  lies  on  the  cord.  The  defere?itial  veins  go  with  the  artery.  They 
unite  and  form  three  or  four  trunks  (pampiniform  plexus)  which  pass  through  the 
inguinal  canal  to  join  and  form  at  the  internal  ring  one  large  vein,  the  spermatic,  which 
accompanies  the  spermatic  artery;  the  right  empties  into  the  vena  cava,  while  the  left 
empties  into  the  left  renal  vein.     They  possess  but  few  valves,  which  are  imperfect. 

The  spermatic  artery,  from  the  aorta,  descends  in  front  of  the  vas  deferens  and  is 
accompanied  by  the  pampiniform  plexus  of  veins.  It  lies  in  the  plexus  with  most  of 
the  veins  in  front  of  it.  These  vessels  lie  in  loose,  fatty  connective  tissue  derived  from 
the  subperitoneal  tissue  along  with  the  atrophied  remains  of  the  peritoneum  (ligament 
of  Cloquet). 

These  structures  are  covered  by  the  sheath  of  the  cord,  composed  ( i )  of  the 
transversalis  fascia  (infundibuliform  fascia),  (2)  cremasteric  fibres  and  fascia  from 
the  internal  oblique,  and  (3)  intercolumnar  fascia  from  the  external  oblique. 

Application.  -  The  cord  is  involved  in  operations  for  varicocele,  hernia,  and  cas- 
tration. In  varicocele  after  the  skin  incision  is  made  a  second  incision  is  required  to 
open  the  sheath  of  the  cord.  This  having  been  done  the  pampiniform  plexus  of  veins, 
which  are  the  ones  enlarged  (varicose)  in  varicocele,  come  into  view.  As  many  of 
these  as  desired  are  then  drawn  out,  ligated  at  both  ends,  and  removed.  In  doing  this 
the  spermatic  artery  may  likewise  be  tied.  The  circulation  is  afterwards  carried  on 
by  the  artery  and  veins  of  the  vas,  the  cremasteric  artery  being  in  the  sheath  externally. 
It  is  wise  not  to  remove  all  of  the  enlarged  veins.  The  vas  deferens  is  recognized  pos- 
teriorly both  by  sight  and  touch  and  is  not  to  be  disturbed.  In  hernia  the  vas  deferens 
sticks  close  to  the  sac,  on  the  posterior  and  inner  side.  It  must  be  sought  for  and  care- 
fully isolated.  In  castration  the  testicle  is  so  movable  that  it  can  be  pushed  up  into  the 
inguinal  region  and  the  incision  through  the  skin  for  its  removal  made  in  that  locality. 
If  done  for  malignant  disease  a  large  portion  of  the  vas  is  removed.     This  can  be  done 


470 


APPLIED 


by  incising  up  to  the  internal  ring  and  drawing  the  vas  out  after  freeing  it  of  any  restrain- 
ing fibrous  bands.  All  bleeding  vessels  are  to  be  ligated  and  the  cord  securely  held.  If 
the  cord  slips  before  all  the  vessels  are  secured,  the  stump  may  retract  in  the  abdomen 
and  dangerous  bleeding  result  before  it  can  again  be  secured  and  the  vessels  ligated. 


THE   URETHRA. 

The  male  urethra  is  variable  in  length,  as  it  can  be  stretched,  therefore  only 
average  measurements  can  be  given.  Its  length  is  20  cm.  (8  in.)  in  the  adult,  8  to 
10  cm.  at  5  years,  and  10  to  12  cm.  at  puberty.  Of  this,  3  cm.  (i^  in.)  is  pros- 
tatic, 0.5  cm.  (  i  in.  )  being  in  the  bladder  wall ;  i  cm.  (  f  in.  )  is  membranous;  16  cm. 
(a  little  over  6  in. )  is  penile.  Its  calibre  varies,  being  narrowest  at  the  meatus 
and  next  narrowest  at  the  membranous  portion.  The  internal  meatus  is  a  little  larger 
than  the  membranous  portion.     The  meatus  admits  a  No.  24  French  sound  (often 

larger) ,  the  membranous  portion  a 
26  to  28.  The  prostatic  portion  is 
the  largest,  admitting  a  No.  32 
sound.  The  bulbous  is  almost  or 
quite  as  large,  admitting  a  30  to  32. 
Therefore  a  sound  which  passes  the 
meatus  should  find  no  further  ob- 
struction. The  fossa  navicularis 
just  beyond  the  meatus  is  larger 
than  the  urethra  beyond  (Fig.  473). 
Distensibility. — The  meatus 
and  membranous  portions  are  the 
least  distensible.  The  former  is 
fibrous  in  character  and  will  not 
stretch.  In  the  membranous  por- 
tion the  support  of  the  superficial 
and  deep  layers  of  the  triangular 
ligament  prevent  dilatation.  The 
prostatic  is  the  most  dilatable  por- 
tion and  the  bulbous  urethra  next. 
Relations. — The  internal 
urethral  meatus  lies  about  6. 25  cm. 
(2|-  in.)  from  the  surface  just  be- 
hind the  middle  of  the  symphysis, 
if  the  body  is  in  a  vertical  position. 
The  membranous  portion  pierces 
the  triangular  ligament,  2.5  cm.  (i 
in. )  or  a  little  less  below  the  sub- 
pubic ligament.  The  lowest  por- 
tion is  just  in  front  of  the  triangular 
ligament.  The  urethra  then  rises 
slightly,  o.  5  cm.  (-|-  in.),  and  finally 
drops  to  the  meatus.  The  subpubic 
curve  of  the  urethra  has  a  radius 
of  about  5  cm.  (2  in.)  and  urethral 
instruments  are  made  with  approx- 
imately this  curvature,  though 
they  vary  much.      The  membra- 


Ureter 


Trigone 


Urethral  ere?*,  (verumontanum) 

Prostatic  ducts 

Utricle  (prostatic  sinus^ 

Ejaculatory  duct 
Membranous  urethra 
Cowper's  gland 

Opening  of  Cowper's  gland 
Bulbous  portion  of  urethra 


Lacunae  and  glands  of  Littrd 


Fossa  navicularis 


Fig.  473. — The  male  urethra. 


nous  urethra  can  be  palpated  at  the  apex  of  the  prostate  by  the  finger  in  the  rectum. 
Structure. — The  urethra  is  composed  of  an  external  layer  of  erectile  tissue 
covering  a  muscular  layer  which  is  continuous  with  that  of  the  prostate  and  bladder. 
Beneath  the  muscular  layer  is  the  submucous,  rich  in  blood-vessels,  on  which  is  laid 
the  mucous  layer.  This  latter  is  covered  with  flat,  pavement  epithelium  in  the  fossa 
navicularis,  and  columnar  epithelium  beyond. 


THE    MALE    EXTERNAL   GENITALS.  471 

The  urethra  contains  small  mucous  glands  opening  on  its  surface — glands  of 
Littre — and  small  pockets  or  recesses,  called  the  lactince  of  Morgagni,  into  which 
the  glands  of  Littre  sometimes  empty.  The  lacunae  are  mostly  in  three  rows  on  the 
roof  of  the  penile  portion  and  open  forward  toward  the  meatus.  A  large  one — 
lacuna  magna — opens  in  the  posterior  portion  of  the  roof  of  the  fossa  navicularis,  a 
couple  of  centimetres  behind  the  meatus.  The  glands  of  Cowper  open  into  the  bul- 
bous urethra  just  in  front  of  the  triangular  ligament.  The  racemose  glands  of  the 
prostate  open  into  the  sides  of  the  floor  of  the  prostatic  urethra,  and  the  ejaculatory 
ducts  open  near  the  middle  line  just  in  front  of  the  urethral  crest  (verumontanum), 
with  the  utricle  (prostatic  sinus)  between. 

The  mucous  walls  of  the  urethra  are  normally  in  contact,  making  a  vertical  slit 
at  the  external  meatus,  a  transverse  one  in  the  penile  portion,  horseshoe  shape  in  the 
prostate,  and  again  transverse  just  before  the  bladder  is  reached. 

Urethral  Muscles. — There  are  two  sets  of  muscles  in  connection  with 
the  urethra;  one  set  might  be  said  to  aid  in  expelling  the  urine  and  the  other 
in  retaining  it.  The  expulsors  are  the  longitudinal  and  circular  fibres  surrounding 
the  urethra  just  outside  the  mucous  membrane  and  the  accelerator  nrintz  or 
biilbocavernosus  muscle.  The  sphincters  are  the  compressor  urethm  or  external 
sphincter  muscle,  and  the  internal  sphincter  at  the  neck  of  the  bladder,  composed 
of  fibres  continued  from  the  bladder  and  prostate.  The  portion  of  these  fibres 
surrounding  the  internal  meatus  just  beneath  the  mucous  membrane  is  called  the 
annulus  urethralis. 

It  has  been  supposed  that  if  the  bladder  becomes  distended  the  internal 
sphincter  involuntarily  relaxes  and  allows  the  urine  to  enter  the  prostatic  urethra, 
and  it  is  then  stopped  by  the  voluntary  contraction  of  the  external  sphincter,  which  is 
the  true  sphincter.  Leedham  Green  {Brit.  Med.  four.,  August,  1906)  claims  that 
the  internal  sphincter  holds  tight  in  the  living  subject  even  when  the  bladder  is  over- 
distended.     Sections  made  of  formalin-hardened  bodies  seem  to  support  this  view. 

Practical  Applications. — A  knowledge  of  both  the  length  and  calibre  of  the 
urethra  is  essential  in  the  use  of  both  catheters  and  bougies  or  sounds.  If  urine 
begins  to  flow  when  a  catheter  is  introduced  20  cm.  we  know  the  urethra  is  of  normal 
length.  Urine  may  flow  when  the  bladder  is  distended  as  soon  as  the  catheter  passes 
the  membranous  portion,  about  17  cm.  (6|<;  in.)  from  the  meatus.  In  hypertrophy 
of  the  prostate  the  prostatic  urethra  is  much  increased  in  length  and  it  may  be  impossi- 
ble to  reach  the  bladder  by  an  ordinary  catheter.  It  may  require  one  25  or  30  cm. 
(10  to  12  in.)  long.  The  position  of  a 
stricture  is  located  by  its  distance  from  the 
meatus.  If  a  sound  is  stopped  by  a  stricture 
inside  of  15  cm.  (6  in.)  from  the  meatus  we 
know  it  is  anterior  to  the  triangular  liga- 
ment. Strictures  are  most  frequent  where 
the  subpubic  curve  is  lowest,  viz.,  at  the 
bulbomembranous  region.  They  are  then 
called  deep  strictures.  They  are  next  most 
frequent  toward  the  anterior  portion,  while 
strictures  of  the  j^rostatic  portion  are  almost 
unknown. 

Passage  of  Sounds  and  Catheters. 
— In  passing  a  catheter  or  sound  its  beak 
should  be  kept  applied  to  the  roof  of  the 
urethra,  otherwise  its  point  will  catch  in 
the  dilated  bulbous  portion  and  strike  on 
the  triangular  ligament  below  the  opening  fig.  474.— Method  of  passing  the  sound.   The  in- 

for  the  urethra.  To  aid  the  beak  to  follow  ^- Sbi^noul  ur'etra!'  """'"*^  *'"  '°""^  '''°""^ 
the  subpubic  curve  the  handle  is  depressed. 

In  difificult  cases  the  index  finger  of  the  opposite  hand  is  introduced  in  the  rectum 
and  the  beak  is  felt  at  the  membranous  portion  a  short  distance  in  front  of  the  apex 
of  the  prostate  and  guided  upward  into  the  bladder  (Eig.  474).  If  the  penis  is 
grasped  near  the  glans  and  drawn  up  the  instrument,  the  urethra  may  so  stretch 


^ff^^^^^^^^  APPLIED    ANATOMY.  ^^^^^^^^ 

that  the  sound  will  not  reach  to  the  bladder.  To  avoid  this  it  should  be  grasped 
lower  down  toward  the  scrotum.  The  urethra  is  so  flexible  and  loose  that  straight 
instruments,  such  as  cystoscopes,  can  readily  be  passed  by  skilful  hands.  In  hyper- 
trophy of  the  prostate,  long  instruments,  with  big  curves  if  of  metal,  are  essential. 
Many  rubber  catheters  are  too  short  for  this  purpose.  In  passing  small,  filiform  bougies 
they  are  to  be  directed  at  first  toward  the  floor  of  the  urethra  to  avoid  the  lacunae  on 
the  roof.  If  they  do  catch  they  are  allowed  to  remain  and  so  prevent  the  ones  sub- 
sequently introduced  catching  in  the  same  place.  The  vascular  net-work  in  the  sub- 
mucous tissue  bleeds  readily  and  the  skill  evinced  by  the  surgeon  in  passing  urethral 
instruments  is  in  inverse  ratio  to  the  amount  of  bleeding  produced. 

Otis  claimed  that  a  penis  3  in.  in  circumference  had  a  normal  urethra  admitting 
a  No.  30,  French  scale,  sound;  2>/i  in-  No.  32;  3^  in.  No.  34;  3^  in.  No.  36,  and 
4  in.  No.  38.  White  and  Martin  state  that  a  3  in.  circumference  admits  a  No.  26 
to  No.  28;  31^  in.  Nos.  28  to  30;  2,^2  in.  Nos.  30  to  32;  3^  in.  Nos.  32  to  34;  and 
a  4  in.  Nos.  34  to  36.  We  agree  with  the  latter,  and  often  the  meatus  though 
normal  in  appearance  must  be  incised  to  admit  the  above  sizes.  The  distensibility 
of  the  urethra  is  such,  especially  in  its  deeper  portions,  that  after  incision  of  the  meatus 
very  large  sounds  can  be  introduced.  For  this  reason  urethrotomes  should  not 
cut  to  the  full  size.  Teevan's  urethrotome  only  cuts  up  to  22  French  and  the 
additional  size  is  obtained  by  stretching  with  sounds.  This  instrument  in  one  case 
was  made  to  cut  to  26  French  but  death  followed  from  hemorrhage  and  a  return  was 
made  to  No.  22.  It  cuts  on  the  roof,  and  the  dorsal  artery  of  the  penis  or  the  artery 
'to  the  bulb  was  probably  divided.  To  avoid  hemorrhage,  deep  strictures  are  treated 
by  dilatation  or  external  urethrotomy  and  penile  strictures  only  are  cut  internally. 
Keegan  has  shown  that  the  calibre  of  the  urethra  in  small  children  is  sufficient  to 
allow  the  use  of  the  lithotrite  and  so  avoid  a  cutting  operation. 

Spas7nodic  stricture  results  from  contraction  of  the  urethral  muscles  due  to  some 
irritation.  This  irritation  may  be  from  the  urine,  from  organic  stricture,  fissure  of 
the  anus,  hemorrhoids,  etc.  It  causes  retention  of  urine,  which  can  be  relieved  by 
passing  a  full-sized  catheter,  or  by  hot  baths,  etc.  Notice  the  firmness  with  which 
the  urethra  grasps  a  sound  as  it  is  withdrawn. 

Traumatic  Stricture.  — This  is  usually  located  in  the  bulbous  portion,  just  in 
front  of  the  triangular  ligament.  The  urethra  is  compressed  between  the  pubic  bone 
and  the  vulnerating  body.  It  is  treated  by  passing  in  a  full-sized  catheter  either 
with  or  without  the  aid  of  a  perineal  incision. 


THE  MALE   PERINEUM. 

The  name  perineum  in  its  broad  sense  is  applied  to  the  structures  of  the  outlet 
of  the  pelvis,  superficial  to  the  levator  ani  muscle.  In  its  restricted  anatomical  sense 
it  is  applied  to  the  subpubic  triangle  as  far  back  as  a  line  joining  the  anterior  portions 
of  the  tuberosities.  In  its  clinical  sense  it  is  the  space  between  the  anus  and  scrotum 
in  the  male  and  anus  and  vulva  in  the  female. 

Bony  Landmarks. — On  examining  the  pelvic  outlet  the  symphysis  pubis  is 
seen  anteriorly  with  the  descending  rami  of  the  pubes  and  ascending  rami  of  the 
ischia  on  the  sides,  leading  to  the  tuberosities.  Posteriorly  is  seen  the  coccyx,  with 
the  spines  of  the  ischia  on  each  side  comparatively  close  to  it.  The  greater  sacro- 
sciatic  ligament  runs  from  the  sacrum  to  the  tuberosity  of  the  ischium,  the  lesser 
from  the  sacrum  to  the  spine  of  the  ischium.  Taken  together  a  diamond-shaped 
space  is  formed.  In  the  female  the  pubic  arch  is  wider,  the  tuberosities  further 
apart,  the  spines  of  the  ischia  do  not  project  so  markedly  inward,  and  the  coccyx 
is  more  movable. 

Perineal  and  Ischiorectal  Regions. — A  line  drawn  from  the  anterior  por- 
tion of  one  tuberosity  to  that  of  the  opposite  side  passes  1.25  cm.  (^  in.)  in  front 
of  the  anus,  and  divides  the  outlet  into  the  urogenital  triangle  or  perineum  in  front, 
and  the  anal  triangle  or  ischiorectal  region  behind. 

Urogenital  Triangle. — The  urogenital  triangle  has  the  symphysis  in  front, 
the  ischiopubic  rami  as  far  back  as  the  anterior  portion  of  the  tuberosities  on  the 


THE    MALE    PERINEUM. 


473 


sides,  and  a  line  joining  the  two  behind.  It  is  closed  by  a  stout  fibrous  membrane 
called  the  triangular  ligament. 

The  central  point  of  the  perineum  is  in  the  median  line  2  cm.  (^  in.)  in 
front  of  the  anus;  it  marks  the  posterior  edge  of  the  triangular  ligament  in  the  median 
line,  and  is  the  point  of  junction  of  the  anteroposterior  and  transverse  muscles. 

Perineal  Fascias. — There  are  four  perineal  fascias,  viz.:  (i)  the  superficial 
layer  of  the  superficial  fascia  ;  (2)  the  deep  layer  of  the  superficial  fascia,  called  also 
CoUes's  fascia  ;  (3)  the  superficial  layer  of  the  deep  fascia,  or  triangular  ligament  ; 
and  (4)  the  deep  layer  of  the  triangular  ligament  or  pelvic  fascia  (Fig.  475). 

The  superficial  layer  of  the  superficial  fascia  is  the  subcutaneous  fatty  tissue, 
and  is  continuous  with  that  of  the  surrounding  parts  and  the  dartos.  When  thick  it 
makes  operations  on  the  deeper  structures  more  difificult  and  sometimes  impossible. 

The  deep  layer  of  the  superficial  fascia  or  Colics' s  fascia  is  the  fibrous  under 
surface  of  the  fatty  superficial  layer.  Posteriorly  it  unites  with  the  posterior  edge  of 
the  triangular  ligament;  laterally  it  is  attached  to  the  ischiopubic  rami;  and  anteriorly 
it  is  continuous  with  the  under  surface  of  the  dartos  of  the  scrotum,  passes  forward 


Deep  layer  of  superficial  fascia 
(Colles) 


Inferior  pudendal  nerve 
External  perineal  nerve 

Internal  perineal  nerve 

Superficial  perineal  artery 

Superficial  perineal  sfjace  and 

triangular  ligament  (superficial' 

layer) 

Transverse  perineal  artery 

Central  point  of  perineum 


Coccyx' 


Dorsal  artery  of  penis 
Ischiocavernosus  muscle 

"Bulbocavernosus  muscle 
Bulb 

.Deep  perineal  space  and 
compres^.or  urethrae  muscle 
Artery  to  the  bulb 
Cowper's  gland 

Deep  transverse  perineal  muscle 
Internal  pudic  artery 
Superficial  transverse  perineal 
muscle 
External  sphincter  ani 

Le\atorani 

Inferior  hemorrhoidal  arteries 

and  nerves 


luteus  maximus 


Fig. 


-The  male  perineum.     The  superficial  perineal  space  is  shown  on  the  left  and  the  deep  perineal  space 

on  the  right. 


to  form  the  suspensory  ligament  and  fibrous  sheath  (Buck's  fascia)  of  the  penis, 
covers  the  spermatic  cord,  and  is  continuous  with  Scarpa's  fascia  (deep  layer  of  the 
superficial  fascia)  of  the  abdomen. 

The  anterior  layer  of  the  triangular  ligament  is  a  firm  fibrous  membrane  stretch- 
ing from  one  tuberosity  to  the  other,  and  attached  to  the  ischiopubic  rami  on  the 
sides  forward  to  the  pubic  arch.  Between  its  upper  edge  and  the  symphysis  runs  the 
dorsal  vein  of  the  penis,  the  dorsal  artery  and  nerve  piercing  it  a  little  lower  and  to 
the  outer  side;  2.5  cm.  (i  in.)  below  the  symphysis  is  the  urethral  opening  with 
the  opening  for  Cowper's  ducts  close  to  it  below,  and  those  for  the  vessels  to  the 
bulb  close  to  it  above.  The  superficial  perineal  vessels  and  nerves  pierce  its  pos- 
terior edge.  The  posterior  edge  of  the  triangular  ligament  blends  with  the  posterior 
edge  of  the  deep  layer  of  the  superficial  fascia  (Colles). 

The  deep  layer  of  the  triang7ilar  ligameyit  is  a  continuation  downward  of  the 
pelvic  fascia.  It  begins  above  on  the  inside  of  the  pelvis,  covering  the  obturator 
muscle  as  the  obturator  fascia  ;  it  then  passes  onto  the  levator  ani  muscles  as  the 
recto-vesical  fascia.  As  the  levator  ani  muscles  do  not  meet  in  front,  the  gap  between 
them  is  filled  in  at  the  median  line  below  or  posteriorly  by  the  termination  of  the 


474 


APPLIED    ANATOMY. 


longitudinal  fibres  of  the  rectum  (prerectalis  muscles  of  Henle,  recto-urethralis  of 
Roux,  Kalischer,  Holl,  Proust,  and  others — see  page  438,  Rectum),  at  the  sides  by 
the  deep  transverse  perinei  and  compressor  urethrae  muscles,  and  anteriorly  by  the 
continuation  of  the  rectovesical  fascia.  From  the  deep  transverse  perinei  muscles 
forward  the  rectovesical  fascia  is  called  the  deep  layer  of  the  triangular  ligament 
(Fig.  476). 

Perineal  Spaces. — There  are  two  perineal  spaces,  one  superficial  space 
between  the  triangular  ligament  (superficial  layer)  and  the  deep  layer  of  the  super- 
ficial fascia  (Colics' s  fascia),  and  the  other,  the  deep  perineal  space,  between  the 
superficial  layer  of  the  triangular  ligament  and  its  deep  layer. 

Superficial  Perineal  Space. — The  superficial  space  has  on  each  side  the  crura 
of  the  penis  attached  to  the  ischiopubic  rami  and  covered  by  the  ischiocavernosus 
(erector  penis)  muscles.  In  the  median  line  anteriorly  lies  the  urethra  with  its 
erectile  tissue  covered  by  the  bulbocavernosus  (accelerator  urinae)  muscle.  The 
posterior  portion  lying  on  the  triangular  ligament  is  called  the  bulb,  and  reaches 
back  to  the  central  point  of  the  perineum.  From  the  central  point  the  superficial 
transverse  perineal  muscles  pass  outward  and  somewhat  backward  to  the  rami  of  the 


Peritoneum 
Pelvic  fascia 


Bladder 
Internal  sphincter 

Prostatic  veins 

Superficial  layer 

triangular  ligament 

Deep  layer  triangular 

ligament 

Membranous  urethra 

Superficial  transverse 
perineal  muscle 

Colles's  fascia 


Internal  sphincter 
External  sphincter 


Fascia  on  bladder 

Fascia  on  rectum 

Separable  space 
(espace  decoUable) 

Seminal  vesicles 

Rectum 

Prostate 


Separable  space 

Recto-urethralis 

muscle 

Cowper's  gland 

Deep  transverse 
perineal  muscle 


Fig.  476. — Perineal  spaces. 


ischia,  and  the  sphincter  ani  passes  back  to  the  coccyx.  'Y^x^  internal  pudic  artery 
comes  forward  from  the  spine  of  the  ischium  through  Alcock's  canal  on  the  outer 
wall  of  the  ischiorectal  fossa,  4  cm.  ( i  ^  in. )  above  the  lower  edge  of  the  tuberosity  ; 
when  it  reaches  the  posterior  edge  of  the  triangular  ligament  it  gives  of?  the  superficial 
perineal  artery,  which  p;erces  it  and  enters  the  superficial  perineal  space,  where  it 
gives  ofi  the  small  transverse  perineal  artery,  and  then  continues  anteriorly  to  the 
base  of  the  scrotum.  The  pudic  nerve  sends  two  branches  forward  in  this  space,  the 
posterior  or  internal  superficial  perineal  toward  the  middle,  and  the  anterior  or 
external  along  the  outer  side  of  the  space  accompanying  the  superficial  perineal 
artery  forward  to  the  scrotum. 

The  Deep  Perineal  Space.  — This  lies  between  the  anterior  and  posterior  layers 
of  the  triangular  ligament.  It  contains  the  compressor  urethrae  (external  vesical 
.sphincter)  muscle  surrounding  the  urethra.  Embedded  in  this  muscle  is  Cowper's 
gland.  Its  duct,  2  cm.  (-^  in. )  long,  pierces  the  anterior  layer  of  the  triangular 
ligament  to  empty  into  the  bulbous  urethra.  Immediately  behind  the  compressor 
urethrae  is  the  deep  transverse  perinei  muscle  passing  across  from  one  ischiopubic 
ramus  through  the  central  point  of  the  perineum  to  the  other.  Running  along  the 
outer  side  of  the  space  is  the  continuation  of  the  internal  pudic  artery.      It  gives  ofi 


THE    MALE    PERINEUM.  475 

the  artery  to  the  bulb  about  3  cm.  (15^  in. )  in  front  of  the  anus,  and  then  about  1.25 
cm.  (}4  in.)  below  the  subpubic  ligament  pierces  the  anterior  layer  of  the  triangular 
ligament  and  divides  into  the  artery  to  the  corpus  cavernosum  and  artery  to  the 
dorsum  of  the  penis  ;  it  is  accompanied  by  the  pudic  nerve,  which  divides  in  like 
manner.  Posteriorly  this  space  is  open,  not  being  closed  by  any  fascia  except  that 
lining  the  under  or  superficial  surface  of  the  levator  ani  muscle  in  the  ischiorectal 
fossa.  In  the  mid-line  the  continuation  of  the  longitudinal  fibres  of  the  rectum 
called  the  prerectal  or  recto-urethralis  muscle  blend  with  the  fibres  of  the  deep 
transverse  perineal  muscle. 

Practical  Application. — The  perineum  is  involved  in  extravasations  of  blood 
and  urine  in  cases  of  rupture  of  the  urethra  ;  also  in  operations  on  the  deep  urethra 
and  bladder  for  the  retention  of  urine  from  stricture  ;  also  in  operations  for  vesical 
calculus,  enlarged  prostate,  and  disease  of  the  seminal  vesicles.. 

Extravasation  of  Urine  and  Blood. — Urinary  extravasation  results  most  often 
from  stricture  and  occurs  almost  always  in  front  of  the  anterior  layer  of  the  triangular 
ligament.  The  urine  enters  the  superficial  perineal  space  and  is  confined  superficially 
by  CoUes's  fascia  and  beneath  by  the  triangular  ligament.  It  is  prevented  from 
going  back  into  the  ischiorectal  space  by  the  union  of  Colles's  fascia  and  the  triangu- 
lar ligament  posterior  to  the  superficial  transverse  perineal  muscles  ;  it  is  prevented 
from  extending  laterally  by  the  attachment  of  Colles's  fascia  to  the  ischiopubic  rami  ; 
hence  it  works  its  way  forward,  distends  the  scrotum,  and  follows  the  spermatic  cord 
up  over  the  crest  of  the  pubis  between  the  spine  of  the  pubis  and  the  median  line. 
Reaching  the  surface  of  the  abdomen  it  is  prevented  from  descending  on  the  thigh 
by  the  attachment  of  the  deep  layer  of  the  superficial  fascia  (Scarpa's  fascia)  just 
below  Poupart's  ligament,  so  it  flows  laterally  and  makes  a  collection  in  the  flank  of 
each  side  above  the  iliac  crests.  It  may  also  infiltrate  the  penis  as  far  forward  as  the 
glans.  The  septum  in  the  median  line  of  the  abdomen,  perineum,  and  scrotum 
hinders  but  does  not  prevent  the  passage  of  the  urine  from  one  side  to  the  other. 
In  treating  it,  numerous  free  incisions  are  made  down  to  the  deep  fascia. 

Rupture  of  the  Urethra. — This  is  produced  by  falling  astride  a  hard  object 
and  jamming  the  urethra  against  the  subpubic  arch,  or  it  results  from  stricture. 
The  rupture  almost  always  involves  the  urethra  just  in  front  of  the  triangular  ligament 
and  sometimes  a  part  of  the  membranous  urethra.  The  superficial  perineal  space 
becomes  infiltrated  with  blood,  and  if  urine  is  passed  it  follows  the  blood,  collecting 
between  Colles's  fascia  and  the  triangular  ligament. 

If  the  membranous  urethra  is  ruptured  the  blood  and  especially  the  urine  may 
escape  into  the  deep  perineal  space  between  the  layers  of  the  triangular  ligament.  It 
may  break  or  leak  through  the  anterior  layer  and  enter  the  superficial  perineal  space  ; 
it  may  work  backward  into  the  ischiorectal  regions  ;  it  may  work  up  and  back 
between  the  prostate  and  rectum  or  breaking  through  the  deep  layer  of  the  triangu- 
lar ligament  it  may  work  up  and  anterior  behind  the  symphysis  pubis,  in  the  pre- 
vesical space  (of  Retzius)  between  the  peritoneum  and  transversalis  fascia  (see  Fig. 
476).      Ruptured  urethra  is  treated  by  perineal  section  or  by  a  retained  catheter. 

Perineal  SectioJi  and  Median  Lithotomy. — In  these  operations  the  bladder  is 
entered  through  an  incision  in  the  median  line  into  the  bulbomembranous  urethra. 
They  are  done  to  divide  deep  strictures,  to  allow  the  urine  to  escape  in  extravasation 
and  rupture  of  the  urethra,  to  remove  foreign  bodies  and  calculi  from  the  bladder,  and 
to  remove  enlargements  of  the  prostate  gland.  The  incision  is  to  be  made  through 
the  raphe  in  the  median  line  ;  ordinarily  it  does  not  begin  farther  forward  than  3  cm. 
( I  ^  in. )  in  front  of  the  anus.  As  the  central  point  of  the  perineum  is  2  cm.  in 
front  of  the  anus  the  incision  passes  through  it  and  divides  the  posterior  fibres  of  the 
bulbocavernosus  muscle  but  involves  little  if  at  all  the  erectile  tissue  of  the  bulb. 
There  is  little  bleeding  if  the  incision  is  kept  in  the  median  line.  The  urethra  is 
entered  about  2.5  cm.  (i  in.)  from  the  surface,  and  the  knife  passed  upward  and 
back  through  the  membranous  and  prostatic  urethra  into  the  bladder,  a  distance  of 
6. 25  to  7. 5  cm.  (2^  to  3  in.  )  from  the  surface.  In  fat  people  or  those  with  enlarged 
prostates  one  may  be  unable  to  reach  the  interior  of  the  bladder  with  the  finger. 
The  membranous  and  prostatic  urethra  is  distensible,  so  that  when  the  former  is 
opened  the  finger  can  be  introduced  and  pushed  into  the  bladder.      In  children  the 


47^^^^^^^^^      APPLIED   ANATt3tf?^^^^^^^^^^^^ 

urethra  may  be  too  small  to  permit  the  entrance  of  the  finger  and  a  Ijlunt  guide  is 
introduced,  along  which  forceps  may  be  passed  to  extract  any  foreign  body,  in 
Cock' s  operation  for  retention  of  urine  the  index  finger  of  one  hand  is  introduced 
through  the  rectum  and  its  tip  placed  at  the  apex  of  the  prostate.  A  straight  knife  is 
then  inserted  2.5  cm.  (i  in.)  in  front  of  the  anus  and  pushed  up  and  inward  into  the 
urethra,  being  guided  by  the  finger  in  the  rectum.  (For  removal  of  enlarged 
prostate  see  page  450.  ) 

Lateral  Lithotomy. — The  incision  is  begun  to  the  left  of  the  median  line  3 
cm.  (iJE^  in.)  in  front  of  the  anus  and  carried  outward  and  back  midway  between 
the  anus  and  tuberosity  of  the  ischium.  The  knife  is  pushed  steadily  on  until  it  enters 
the  groove  in  the  stafl  and  thence  backward  into  the  bladder.  The  artery  to  the 
bulb  is  to  be  avoided  by  not  going  more  than  3  cm.  in  front  of  the  anus.  The  rec- 
tum is  to  be  avoided  by  having  it  empty,  by  hooking  the  staff  in  the  urethra  well  up 
to  the  pubic  arch,  thus  drawing  the  urethra  up,  and  by  inclining  the  knife  obliquely 
outward.  The  internal  pudic  artery  is  to  be  avoided  by  keeping  away  from  the  ramus 
Of  the  ischium.  Too  free  an  incision  of  the  prostate  is  bad  because  urinary  infiltration 
is  liable  to  occur  in  the  pelvic  fascia,  also  an  accessory  pudic  artery,  which  if  present 
may  run  along  the  side  of  the  prostate,  may  thus  be  wounded.  Usually  the  bleeding 
is  slight  and  comes  from  the  division  of  the  superficial  transverse  perineal  and  branches 
of  the  inferior  hemorrhoidal  arteries  and  the  prostatic  plexus  of  veins.  (For  Perineal 
Prostatectomy  see  page  450  and  Seminal  Vesicles  page  452.) 

Anal  Triangle  and  Ischiorectal  Region. — The  anal  triangle  is  made  by  the 
superficial  transverse  perineal  muscles  forming  its  base  and  the  tip  of  the  coccyx  its 
apex.      It  contains  the  anal  canal  with  the  ischiorectal  fossae  on  each  side. 

The  ischiorectal  fossa  is  wedge-shaped,  its  base,  extending  between  the  tuber- 
osity of  the  ischium  and  the  anus,  is  about  2.5  cm.  (i  in.)  in  breadth,  and  its  apex 
extends  up  5  to  7.5  cm.  (2  to  3  in. ),  to  the  junction  of  the  levator  ani  and  internal 
obturator  muscles.  Its  inner  wall  is  formed  by  the  levator  ani  and  coccygeus  muscles 
and  its  outer  wall  by  the  obturator  internus  muscle.  Its  deepest  extreme  posterior 
portion  constitutes  Xh^o.  posterior  recess.  This  communicates  superficially,  beneath  the 
coccygeal  attachment  of  the  external  sphincter,  with  the  fossa  of  the  opposite  side 
(see  Fig.  475,  page  473). 

The  anterior  recess  (pubic,  Waldeyer)  runs  forward  between  the  prostate  gland 
internally  and  the  ischiopubic  ramus  externally  ;  the  deep  and  superficial  transverse 
perinei  muscles  and  the  deep  layer  of  the  triangular  ligament  are  superficial  to  it. 

The  ititernal  pudic  vessels  and  pudic  nerve  lie^on  the  internal  obturator  muscle 
and  ramus  of  the  ischium  in  a  fibrous  canal  formed  by  the  obturator  fascia.  It  is 
called  Alcock' s  canal 2ind  is  4  cm.  (i^  in.)  above  the  tuberosity. 

^\iQ.  inferior  hemorrhoidal  vessels  and  nerves  enter  the  ischiorectal  fossa  at  its 
posterior  and  outer  side  and  run  on  the  surface  of  the  levator  ani  muscle  toward  the 
anus.  The  superjicial peri7ieal  \ess&\s  and  nerves  enter  the  fossa  anteriorly  and  imme- 
diately pierce  the  posterior  edge  of  the  superficial  perineal  (Colics' s)  fascia  to  supply 
the  structures  between  it  and  the  superficial  layer  of  the  triangular  ligament. 

Practical  Application.  — The  principal  affection  of  the  ischiorectal  fossa  is  abscess. 
This  is  probably  started  by  violence  and  infected  from  the  rectum.  It  commonly 
tends  to  point  through  the  skin  or  open  into  the  rectum.  On  account  of  its  ten- 
dency to  burrow  it  is  to  be  opened  early.  This  is  done  by  making  an  incision  of 
ample  size  through  the  skin  and  then  opening  the  abscess  by  blunt  dissection  in 
order  to  empty  all  pockets.  Bleeding  is  usually  slight  because  the  vessels  lie  deep 
and  escape  being  wounded.  Should  the  abscess  not  break  externally  it  may  do  so 
internally.  If  superficial  it  pierces  the  anal  canal  between  the  external  and  internal 
sphincters  and  makes  an  opening  at  about  the  white  line.  If  it  is  very  deep  it  may 
open  into  the  ampulla  of  the  rectum  above  the  internal  sphincter  (see  page  443)- 
It  is  more  common  for  pus  to  burrow  down  into  the  ischiorectal  space  through  the 
levator  ani  than  it  is  for  it  to  burrow  up  from  the  ischiorectal  fossa  (Tuttle).  There- 
fore in  extensive  ischiorectal  abscesses  communicating  with  the  interior  of  the  pelvis 
one  should  look  for  the  origin  of  the  trouble  above.  An  abscess  on  one  side  is  liable 
to  be  followed  by  one  on  the  other  and  pus  quite  commonly  crosses  the  median  line 
posterior  to  the  anus. 


THE    BACK   AND    SPINE. 


477 


THE  BACK  AND  SPINE. 

SURFACE   ANATOMY. 

On  examining  the  back  of  a  person  standing  upright  a  mediayi  furrow  is  seen 
(Fig.  477).  In  the  bottom  of  this  the  tips  of  the  spinous  processes  can  be  feh.  If  the 
back  is  bent  these  processes  can  be  distinctly  seen;  they  should  form  a  straight  line. 
The  second  cervical  spine  can  be  felt  by  deep  pressure  in  a  relaxed  neck.  The  sixth 
is  usually  the  first  one  visible  and  the  seventh  cervical  and  first  dorsal  are  very  promi- 
nent, often  the  latter  the  more  so.  The  furrow  ends  abruptly  at  the  top  of  the  sacrum. 
From  this  point  down  to  near  the  top  of  the  gluteal  fold  is  a  tjiangidar  space  with 
its  base  above  and  apex  downward.  Its  apex  marks  the  third  sacral  spine,  and  just 
above  this  latter,  opposite  the  second  sacral  spine,  on  each  side  can  be  felt  the  posterior 
superior  iliac  spines.  The  erector  spince  (sacrolumbalis)  muscles  form  elevations  on 
each  side  of  the  furrow,  most  marked  in  the  lumbar  region.  In  muscular  people  the 
erector  spinse  is  seen  to  consist  of  two  parts  :  an  inner  longissimus  dorsi  muscle,  and 
an  outer  iliocostalis.     Above,  the  projections  of  the  scapulce  are  visible.     If  the  arms 


Seventh  cervical 
Outer  end  of  clavicle 
Acromion  process 

Root  of  spine  of  scapula 

Median  furrow 
AnKle  of  scapula 


Depression  along  outer 
edge  of  erector  spinas 

Mass  of  erector  spinas 

muscles 

Posterior  superior 
spine  of  ilium 

Third  sacral  spine 


Fig.  477. — Surface  anatomy  of  the  back. 

are  by  the  sides  the  posterior  border  of  the  scapula  is  parallel  to  the  median  line. 
The  root  of  the  spine  of  the  scapula  in  a  muscular  person  makes  a  depression.  It  is 
opposite  the  third  dorsal  spine  or  the  body  of  the  fourth  thoracic  vertebra,  and  marks 
the  upper  end  of  the  fissure  of  the  lungs.  The  spine  of  the  scapula  is  subcutaneous 
and  can  be  traced  out  to  the  acromion  process.  The  lower  angle  of  the  scapula  is 
opposite  the  upper  border  of  the  eighth  rib;  the  upper  angle  covers  the  second  rib 
but  its  tip  is  level  with  the  first. 

In  the  lumbar  region  the  erector  spinse  muscle  forms  a  clearly  marked  promi- 
nence. The  twelfth  rib  usually  projects  beyond  its  outer  edge,  which  is  marked  by  a 
depression  separating  it  from  the  abdominal  muscles  in  front.  It  is  through  this 
depression  that  operations  on  the  kidney  are  performed  (see  page  428).  The  dis- 
tance between  the  twelfth  rib  and  crest  of  the  ilium  is  usually  6. 25  cm.  (2^  in. )  but  it 
may  be  more  and  is  often  less.  Just  above  the  middle  of  the  crest  of  the  ilium  is 
Petit' s  triangle  (page  394);  and  to  the  inner  side  of  the  lower  third  of  the  poste- 


478 


APPLIED  ANATOMY. 


rior  edge  of  the  scapula  is  another  small  triangle.  Its  upper  side  is  formed  by  the 
trapezius,  its  lower  by  the  latissimus  dorsi,  and  its  outer  by  the  posterior  edge  of  the 
scapula.  As  the  lung  is  nearest  the  surface  at  this  point  it  is  often  chosen  for  physical 
examination,  puncture,  etc. 

THE  VERTEBRAL  COLUMN. 

Normally  the  spinal  column  is  composed  of  seven  cervical,  twelve  dorsal,  five 
lumbar,  five  sacral,  and  four  to  five  coccygeal  vertebrae.  The  sacral  vertebrae  tend 
to  fuse  together,  forming  a  single  bone,  the  sacrum.  This  fusion  is  complete  at  the 
twenty-fifth  year.      The  coccygeal  vertebrae  join  later,  fusion  occurring  in  middle  life. 

Sometimes  in  advanced  age  the  coccyx  and  sacrum 
fuse  together.  The  cervical  vertebrae  are  almost 
always  seven  in  number,  but  both  the  dorsal  and 
lumbar  vary  much  more  frequently  than  is  usually 
supposed.  The  occurrence  of  thirteen  instead  of 
twelve  ribs  on  a  side  is  not  uncommon  and  I  have 
seen  skeletons  with  only  eleven.  A  rudimentary 
cervical  rib  also  occasionally  occurs. 

The  tips  of  the  spinous  processes  of  the  cervical 
vertebrae,  the  first  two  dorsal,  and  last  four  lumbar, 
pass  almost  horizontally  backward  and  are  there- 
fore nearly  opposite  the  bodies  of  the  vertebrae  to 
which  they  are  attached.  The  tips  of  the  spines 
from  the  third  to  the  last  dorsal  inclusive,  however, 
are  opposite  the  bodies  of  the  next  vertebrae  below 
them,  being  inclined  downward,  while  the  tip  of  the 
first  lumbar  is  about  opposite  the  intervertebral  disk 
beneath. 

Ciarves. — At  the  third  month  of  intra-uterine 
life  there  is  only  one  large  curve,  convex  poste- 
riorly. At  birth  there  are  two  curves,  each  convex 
posteriorly,  a  dorsal  and  sacral,  probably  to  accom- 
modate the  thoracic  and  pelvic  viscera;  after  the 
erect  position  is  assumed  the  cervical  and  lumbar 
curves  become  established.  The  cervical  passes 
into  the  dorsal  curve  at  the  middle  of  the  second 
thoracic  vertebra  and  the  dorsal  into  the  lumbar  at 
the  middle  of  the  last  thoracic  vertebra.  (Fig. 
478).  Laterally,  there  is  a  slight  curve  in  the 
dorsal  region  with  its  convexity  to  the  right,  prob- 
ably due  to  the  increased  use  of  the  right  hand. 

Movements. — Flexion  and  extension  are  free 
in  the  neck  and  lumbar  region,  rotation  is  slight  in 
the  cervical  region,  free  in  the  upper  portion  of  the 
dorsal,  and  gradually  diminishes  to  be  absent  in  the 
lumbar  region. 


I.  lumbar 


I.  sacral 


■I.  coccygeal 


DEFORMITIES  OF  THE  SPINAL  COLUMN. 


Fig.  478. — Lateral  view  of  the  adult  spine, 
showing  its  curves.    (Piersol.) 


The  weight  of  the  head  is  borne  on  the  condyles 
of  the  occiput,  and  a  perpendicular  let  fall  from  the 
condyles  passes  through  the  points  where  the  spinal 
curves  pass  one  into  the  other  and  thence  through  the  anterior  edge  of  the  promontory 
of  the  sacrum.  Hence  if  one  curve  is  altered  by  injury  or  disease  it  is  of  necessity 
accompanied  by  a  corresponding  change  in  the  curve  on  the  opposite  side  of  the 
perpendicular  line.  The  first  is  called  the  primary  curve  and  the  other  the  second- 
ary one.  In  anteroposterior  curvatures  these  curves  are  exaggerations  of  the  normal 
curves  but  in  lateral  curvatures  they  are  newly  formed  because  there  is,  practically, 


THE  VERTEBRAL  COLUMN. 


479 


no  normal  lateral  curve  in  the  spinal  column.  The  spine  may  project  abnormally 
backward,  forming  a  kyphosis;  forward,  lordosis;  and  more  or  less  laterally,  scoliosis. 

Kyphosis. — The  vertebrae  are  supported  one  above  another  by  two  points  of 
contact,  a  posterior  one,  formed  by  the  articular  processes,  and  an  anterior  one,  formed 
by  the  bodies  of  the  vertebrae  separated  by  the  intervertebral  disks.  Of  these  two 
supports,  that  afjforded  by  the  bodies  and  disks  is  the  more  important.  The  laminae 
and  pedicles  with  their  attached  articular  processes  are  frequently  fractured,  but  the 
shape  of  the  vertebral  column  is  but  little  altered;  even  after  laminectomy  the  spine 
remains  comparatively  straight.  When,  however,  the  bodies  of  the  vertebrae  are 
destroyed,  as  occurs  in  tuberculous  disease  and  crushing  injuries,  the  anterior  portion 
of  the  spine  collapses  and  the  parts  bend,  the  spines  projecting  backward  forming  a 
hump  (Fig.  479).  Thus  the  angular  character  of  the  deformity  is  explained  by  the 
method  of  construction  of  the  spine. 

Besides  this  angtdar  kyphosis  there  is  another  form,  due  to  general  weakness. 
This  is  seen  in  rachitic  children  ;  owing  to  a  weakness  of  all  the  tissues  the  normal 
curves  become  increased  and,  as  in  young  children,  the  normal  spine  has  one  long 
general  cur\'e  with  its  convexity  posteriorly,  we  find  this  cur\e  greatly  increased, 
forming  a  rachitic  kyphosis. 

Lordosis. — When  a  child  is  born  and  for  some  time  thereafter  the  spine  pos- 
sesses a  slight  dorsal  and  a  pelvic  curve.  When  it  sits  up  and  begins  to  hold  its 
head  erect  and  look  around,  the  cervical  curve  develpps.      Still  later  when  it  begins 


w 


Fig.  479. — Kyphosis  or  angular 
anteroposterior  curvature,  usually 
due  to  caries  of  the  bodies  of  the 
vertebrae. 


Fig.  480. — Lordosis  or  hollow 
back,  caused  by  congenital  luxa- 
tion of  the  hips. 


Fig.  481 . — Scoliosis  or  lateral  cur. 
vature  of  the  spine. 


to  walk  the  lumbar  curve  develops.  An  increase  in  the  lumbar  curve,  or  lordosis, 
is  caused  by  general  weakness  as  just  described  for  rachitic  kyphosis,  or  it  results 
from  some  disease  or  injury  interfering  with  the  lower  extremities  and  thus  disturbing 
the  centre  of  gravity.  This  occurs  in  congenital  luxation  of  the  hips  (Fig.  480),  in 
which  the  heads  of  the  femurs  are  set  too  far  back,  and  also  in  rachitic  deformities 
of  the  lower  extremities,  hip  disease,  etc.  Likewise,  if  the  abdominal  viscera  are 
unduly  prominent,  the  thoracic  region  is  carried  further  back  to  maintain  the  bal- 
ance, and  hence  a  hollow  back  is  produced.  Ankylosis  of  the  hip  in  a  flexed 
position  causes  lordosis  when  the  limb  is  brought  straight  down  as  in  walking. 
Therefore  in  cases  of  lordosis  one  should  remember  that  it  is  a  secondary  condition 
dependent  on  diseased  conditions  of  the  viscera  or  extremities  and  is  comparatively 
rarely  an  independent  affection. 

Scoliosis. — A  normal  spine  is  either  absolutely  straight  or  very  slightly  convex 
to  the  right  in  the  dorsal  region,  probably  due  to  the  increased  use  of  the  right  hand. 
While  scoliosis  is  called  lateral  curvature  of  the  spine,  it  is  not  a  simple  lateral 
bending,  but  is  a  complex  distortion  (Fig.  481).  R.  W.  Lovett  has  show^n  that  a 
flexible  straight  rod  can  be  bent  in  one  plane  either  anteroposteriorly  or  laterally,  but 


48o 


APPLIED  ANATOMY. 


that  a  curved  rod  cannot  be  bent  laterally  without  twisting  or  rotating  Inasmuch 
as  the  human  spine  is  curved  convexly  backward  in  the  dorsal  region  and  convexly 
forward  in  the  lumbar  region,  lateral  bending  is  accompanied  by  rotation  of  the 
vertebrae  and  their  attached  ribs.  The  bodies  of  the  vertebrae  are  carried  toward  the 
side  of  the  convexity  of  the  curve  and  the  ribs  on  that  side  project  backward,  pro- 
ducing a  marked  hump  and  often  an  elevation  of  the  shoulder.  As  a  primary  cur\e 
forms,  an  attempt  is  made  to  restore  equilibrium  by  bending  the  remaining  portion  of 
the  spine  in  the  opposite  direction,  hence  the  curves,  if  of  long  duration,  are  double 
or  compound,  and  these  secondary  curves  are  called  compensating  curves.  Marked 
lumbar  curves  are  usually  accompanied  by  prominence  of  the  hip  on  the  side  of  the 
convexity,  but  the  pelvis  usually  remains  level.  Should  the  length  of  the  limbs  be 
unequal,  allowing  tilting  of  the  pelvis,  the  prominence  of  the  hip  would  be  on  the 
side  of  concavity.  It  is  obvious  that  the  weight  of  the  body  tends  to  aggravate 
these  pathological  curves.  The  treatment  of  scoliosis  is  directed  to  correcting  these 
faulty  curves  by  exercises  and  appliances  intended  to  support  and  stretch  the  body 
on  the  contracted  or  depressed  side  and  restore  the  tone  and  power  to  the  relaxed 
muscles  and  tissues  of  the  opposite  side. 

Spina  Bifida.  —  The  spinal  canal  is  formed  by  the  laminae  of  the  vertebrae 
arching  over  and  uniting  posteriorly.     This  union  begins  in  the  dorsal  region  and 

progresses  towards  the  head  and  sacral  regions. 
Failure  of  union  constitutes  spina  bifida.  It  is 
most  frequent  in  the  lumbar  and  sacral  regions. 
Usually  a  sac  formed  of  the  spinal  membranes 
protrudes  and  contains  the  spinal  cord  flattened 
out  like  a  strap  passing  down  on  its  posterior  sur- 
face, but  sometimes  the  sac  contains  no  nervous 
elements.  Frequently  the  sac  is  so  thin  that  it 
soon  inflames,  ruptures,  and  allows  escape  of  the 
cerebrospinal  fluid,  and  death  ensues  from  menin- 
gitis. The  parts  below  are  not  infrequently  para- 
lyzed and  hydrocephalus  may  coexist.  Operative 
procedures  have  been  frequently  successful  in 
mild  cases,  but  in  extensive  lesions  they  have 
been  quite  fatal,  and  even  when  primarily  suc- 
cessful may  be  followed  by  the  development  of 
hydrocephalus. 

AFFECTIONS   OF   THE   SPINAL 
COLUMN. 

Caries  of  the  Spine. — While  caries  of  any 
part  of  the  vertebrae  may  occur  from  injury,  it  is 
almost  always  the  result  of  tuberculous  disease 
in  the  bodies  ;  the  pedicles,  laminae,  and  proc- 
esses remain  unaffected.  As  the  bodies  become 
destroyed  the  anterior  portion  of  the  spine  col- 
lapses, and  this  causes  a  projection  of  the  spines 
of  the  affected  vertebrae  posteriorly  or  kyphosis. 
This  projection  of  one  or  more  spinous  processes 
is  the  surest  indication  of  spinal  caries  or  Pott's 
disease. 

There  is  also  rigidity  of  the  affected  region. 
This  is  recognized  by  the  attitude  assumed  and 
by  having  the  patient,  if  an  adult,  bend  the  back 
anteroposteriorly.  Small  children  should  be 
placed  flat  on  a  table,  face  down,  and  then  gradu- 
ally raised  by  the  feet.  If  the  spine  is  normal  the  child  will  readily  bend  in  the  lumbar 
and  lumbodorsal  regions.  The  movable  regions,  embracing  the  cervicodorsal  and  dor- 
solumbar  vertebrae,  are  the  sites  most  frequently  affected.    Distention  of  the  abdomen 


Fig.  482. — Psoas  abscess  originating  from 
spinal  caries  of  the  dorsolumbar  vertebne 
and  following  the  psoas  muscle  to  the  groin. 
(From  a  sketch  by  the  author  of  a  specimen 
in  the  Mutter  Museum  of  the  College  of 
Physicians). 


THE  VERTEBRAL  COLUMN.  481 

and  pain  occur  from  involvement  of  the  spinal  nerves.  The  tenth  dorsal  nerve 
arrives  anteriorly  at  the  level  of  the  umbilicus,  the  twelfth  is  midway  between  the 
umbilicus  and  symphysis  and  also  sends  an  iliac  cutaneous  branch  a  couple  of  inches 
behind  the  anterior  superior  spine  to  the  skin  of  the  buttock,  and  below  and  in  front 
of  the  great  trochanter.  The  abdomen  above  the  external  inguinal  ring  is  supplied 
by  the  hypogastric  branch  of  the  iliohypogastric  from  the  first  lumbar. 

Psoas  abscess  is  common.  The  psoas  muscle  arises  from  the  lower  border  of 
the  body  of  the  twelfth  dorsal  and  the  bodies  of  all  the  lumbar  vertebrae.  The  pre- 
vertebral fascia  covering  the  bodies  of  the  vertebrae  is  continued  downward  over  the 
psoas  muscle  as  its  sheath.  Therefore  when  pus  forms  in  the  bone  it  enters  the 
sheath  and  follows  it  downward  under  Poupart's  ligament,  usually  just  outside,  but 
sometimes,  as  it  gets  still  lower  down,  to  the  inside  of  the  femoral  vessels  (Fig.  482). 
At  other  times  it  works  its  way  backward  and  points  in  the  angle  between  the  erector 
spinae  muscle  and  the  twelfth  rib,  or  along  the  edge  of  the  erector  spinae  lower  down, 
or  a  little  farther  out  above  the  top  of  the  middle  of  the  crest  of  the  ilium  at  Petit' s 
triangle  (see  page  394).  It  may  also  find  an  exit  through  the  great  sacrosciatic 
notch  and  point  on  the  posterior  aspect  of  the  thigh.  Pus  originating  in  the  cervical 
region  produces  retropharyngeal  abscesses,  which,  if  involving  the  second  to  the 
fifth  cervical  vertebrae,  may  either  point  in  the  pharynx  or  work  outward  to  the 
posterior  edge  of  the  sternomastoid  muscle  (see  page  156). 

INJURIES    OF   THE   SPINAL   COLUMN. 

The  vertebrae  may  be  dislocated  and  fractured. 

Dislocation  is  rarer  than  fracture  ;  it  is  most  common  in  the  cervical  region. 
The  cervical  vertebrae  have  their  articular  facets  sloping  downward  and  backward, 
hence  dislocation  occurs  when  the  upper  vertebrae  are  pushed  in  front  of  the  lower. 


Mastoid  process 
Transverse  process 
of  atlas 

Second  cervical 

vertebra 


Fig.   483. — Anterior  view,  showing   relation  Fig.  484. — Lateral  view,  showing  relation  of  transverse 

of  transverse  process  of  atlas  to  tip  of  mastoid  process  of  atlas  to  tip  of  mastoid  process. 


process 


The  cervical  spine  normally  has  but  slight  rotation,  hence  when  luxated  one  articu- 
lar surface  is  rotated  or  pushed  over  and  in  front  of  the  one  below,  the  opposite 
articular  surface  acting  as  the  axis  and  the  distance  between  the  two  articulations  as 
the  radius  of  the  arch  in  which  the  luxated  parts  move.  The  elevation  of  the  lux- 
ated articular  process  over  the  one  below  is  favored  by  the  bending  of  the  spine 
above  toward  the  opposite  side.  The  head  is  rotated  and  inclined  toward  the  un- 
injured side.  Bilateral  luxation  is  rare  without  associated  fracture.  It  is  produced 
by  anterior  flexion,  and  the  head  and  neck  are  inclined  forward  while  the  lower 
vertebra  of  the  dislocated  joints  inclines  backward,  producing  a  kyphotic  condition. 

Luxation  affects  most  often  the  fourth,  fifth,  and  sixth  cervical  vertebrae.  The 
atlas  may  be  dislocated  forward  or  backward  by  rupture  of  the  transverse  ligament, 
fracture  of  the  odontoid  process,  or  by  a  slipping  of  the  process  under  the  ligament. 

Luxation  of  the  atlas  laterally  is  very  rare,  owing  to  there  being  normally  a  total 
rotation  of  60  degrees. 

31 


482 


APPLIED    ANATOMY. 


The  upper  three  vertebrae  can  be  palpated  on  their  anterior  surfaces  by  the  finger 
introduced  into  the  mouth. 

Posteriorly  the  second,  third,  and  fourth  spines  are  too  deeply  placed  between 
the  muscles  to  be  palpated. 

To  reduce  the  luxation  an  anaesthetic  is  given  to  relax  the  muscles,  and  cautious 
extension  is  made  and  the  head  gently  rotated. 

Fracture  of  the  spine  is  frequently  associated  with  luxation.  It  is  most  frequent 
low  down  in  the  cervical  region  and  at  the  junction  of  the  dorsal  and  lumbar  ver- 
tebrae, these  being  the  places  where  the 
more  fixed  dorsal  portion  passes  into  the 
more  movable  cervical  and  lumbar  por- 
tions (Fig.  485).  The  vertebrae  are  sup- 
ported at  three  points — the  bodies  and  the 
two  articular  processes.  The  spinous  and 
articular  processes  are  rarely  fractured 
alone;  they  may  be  broken,  however,  by 
direct  violence.  The  laminae  on  each  side 
of  the  articular  processes  may  be  broken 
and  the  detached  part  with  the  spinous 
process  may  be  pushed  inward,  injuring  the 
cord.  Fracture  of  the  bodies  is  most  fre- 
quent and  is  due  to  anterior  flexion.  The 
bodies  and  intervertebral  disks  are  com- 
pressed, crushed,  and  torn.  This  is  accom- 
panied by  either  luxation  or  fracture  of  the 
articular  processes,  and  occurs  most  often 
in  the  region  of  the  lower  dorsal  vertebrae. 
Injury  to  the  cord  is  common.  The  parts 
are  not  often  fixed  in  a  markedly  displaced 
position,  as  is  the  case  with  luxations  of  the 
neck,  hence  attempts  at  reduction  are  rarely 
necessary  and  fixation  is  to  be  aimed  for  in 
treatment.  The  site  of  injury  is  determined 
not  only  by  an  examination  of  the  spinous  processes  but  also  by  the  extent  of  inter- 
ference with  the  functions  of  the  cord  (see  page  483). 


Pedicle 
Articulation 


,  Fig.  485. — Showing  the  method  of  articulation 
of  the  eleventh  and  twelfth  dorsal  and  the  first  and 
second  lumbar  vertebrae. 


SPINAL    CORD    AND    ITS  MEMBRANES. 

The  spinal  cord  in  the  male  is  45  cm.  (18  in.)  long.  In  the  foetus  of  three 
months  the  cord  extends  to  the  end  of'  the  spinal  canal;  at  birth  it  has  risen  to  the 
third  lumbar  vertebra,  and  in  the  adult  it  is  opposite  the  lower  border  of  the  first. 
It  will  thus  be  seen  that  the  point  of  exit  of  the  spinal  nerves  from  the  cord  is  always 
some  distance  higher  up  than  their  exit  from  the  intervertebral  foramina.  The  cord 
is  enlarged  in  the  cervical  and  lumbar  regions,  the  cervical  enlargement  ending 
opposite  the  second  dorsal,  and  the  lumbar  enlargement  beginning  about  opposite 
the  tenth  dorsal  vertebra  and  decreasing  gradually.  These  enlargements  correspond 
with  the  origin  of  the  nerves  to  the  upper  and  lower  extremities. 

The  spinal  cord  is  divided  into  so-called  segments.  These  are  thirty-one  in 
number ;  eight  are  cervical,  twelve  thoracic,  five  lumbar,  five  sacral,  and  one  coccy- 
geal. Each  segment  embraces  that  portion  of  the  cord  which  gives  exit  to  one  pair 
of  anterior  or  motor  root  fibres  and  receives  one  pair  of  posterior  or  sensory  root 
fibres.  These  segments  are  a  variable  distance  above  the  point  of  exit  of  the  nerves 
from  the  bony  spinal  column.  Besides  motor  and  sensory  functions  they  exercise 
control  over  certain  reflex  movements  and  functions.  The  control  of  the  bladder  and 
rectum  is  located  in  the  fifth  and  sixth  sacral  segments;  the  cremasteric  reflex  is  gov- 
erned by  the  first  and  second  lumbar  ;  the  plantar  or  Babinski  reflex  by  the  first  to 
third  sacral,  as  is  also  ankle  clonus;  and  the  patella  reflex  by  the  second  and  third 
lumbar  segments.  They  likewise  exert  a  trophic  influence,  and  the  appearing  of 
bed  or  pressure  sores  without  ample  cause  is  presumptive  evidence  of  a  spinal  lesion 
of  the  segments  supplying  the  part. 


THE  VERTEBRAL  COLUMN. 


483 


TRANSVERSE   SPINAL   LESIONS. 

In  endeavoring  to  localize  transverse  lesions  of  the  cord,  such  as  result  from 
traumatism,  tumors,  etc.,  one  must  bear  in  mind  that  the  spinal  nerves  originate  from 
segments  in  the  cord  some  distance  above  where  they  make  their  exit  from  the  spinal 


Fig.  486. — Diagram  of  distribution  of  cutaneous  nerves,  based  on  figures  of  Hasse  and  of  Cunningham.  On 
right  side,  areas  supplied  by  indicated  nerves  are  shown;  on  left  side,  points  at  which  nerves  pierce  the  deep  fascia. 
V,  V-,  V\  divisions  of  fifth  cranial  nerve;  GA,  great  auricular;  GO,  SO,  greater  and  smaller  occipital;  SC,  super- 
ficial cervical;  St,  CI,  Ac,  sternal,  clavicular,  and  acromial  branches  of  supraclavicular  {ScD;  Ci,  circumflex: 
MS,  musculospiral ;  IH,  intercostohumeral;  LlC,  IC,  lesser  internal  and  internal  cutaneous;  EC,  external 
cutaneous;  IH,  iliohypogastric;  //,  ilio-inguinal;  T'^,  last  thoracic;  GC,  genitocrural;  EC,  external  cutaneous; 
MC,  middle  cutaneous;  /C"  internal  cutaneous;  P,  pudic;  5S,  small  sciatic;  O,  obturator;  C,  T,  L,  and  S,  cervical, 
thoracic,  lumbar,  and  spinal  nerves.     (Piersol.) 

foramina.  Chipault  (quoted  by  Starr)  gives  the  following  practical  rule:  "In  the 
cervical  region  add  one  to  the  number  of  the  vertebra,  and  this  will  give  the  segment 
opposite  to  it.     In  the  upper  dorsal  region  add  two;  from  the  sixth  to  the  eleventh 


APPLIED    ANATOMY. 

dorsal  vertebra  add  three.  The  lower  part  of  the  eleventh  dorsal  spinous  process 
and  the  space  below  it  are  opposite  the  lower  three  lumbar  segments.  The  twelfth 
dorsal  spinous  process  and  the  space  below  it  are  opposite  the  sacral  segments."  The 
spinal  cord  ends  at  the  lower  part  of  the  first  lumbar  vertebra. 

The  areas  of  cutaneous  sensibility  aid  in  determining  the  seat  of  the  lesion.  The 
nerves  supplying  these  various  areas  are  shown  in  Fig.  486. 

Lesions  above  the  fourth  cervical  nerve  are  very  speedily  fatal.  The  muscular 
paralyses,  as  guides  to  the  seat  of  the  lesion  in  the  cervical  region,  are  given  by 
Thorburn  as  follows: 


Supraspinatus  and  infraspinatus  . 
Teres  minor  (?) 

f  Biceps 

\  Brachialis  anticus 

Deltoid 

Supinator  longus 

Supinator  brevis  (?) 

Subscapularis 

Pronators 

Teres  major 

Latissimus  dorsi 

Pectoralis  major 

(  Triceps 

\  Serratus  magnus 

Extensors  of  the  wrist     .... 

Flexors  of  the  wrist 

Interossei 

Other  intrinsic  muscles  of  the  hand 


Fourth  cervical  nerve. 


Fifth  cervical  nerve. 


Sixth  cervical  nerve. 


Seventh  cervical  nerve. 
Eighth  cervical  nerve. 

V  First  dorsal  nerve. 


In  fractures  of  the  dorsal  region  Thorburn  has  shown  that  the  lesion  is  usually 
two  vertebrae  higher  than  the  nerve  coming  out  from  below  the  displaced  vertebra. 
They  cause  paralysis  of  the  abdominal  muscles,  legs,  bladder,  and  rectum. 

According  to  Starr,  fractures  in  the  region  of  the  last  two  dorsal  vertebrae  cause 
anaesthesia  up  to  Poupart's  ligament,  and  if  the  patient  recovers  the  thighs  remain 
paralyzed.  In  fractures  of  the  upper  part  of  the  lumbar  region  the  paralysis  may  be 
limited  to  the  legs  below  the  knees  but  involves  the  bladder  and  rectum.  Recovery 
leaves  the  patient  with  some  power  of  getting  about  on  crutches  with  the  aid  of 
apparatus  to  keep  the  ankles  and  knees  firm,  as  the  thighs  are  under  voluntary 
control. 

Lesions  below  the  first  lumbar,  those  of  the  cauda  equina,  give  paralysis  of 
the  feet  and  peronei,  loss  of  control  of  the  bladder  and  rectum,  and  anaesthesia  in  the 
saddle-shaped  area  on  the  buttocks,  about  the  anus,  and  on  the  posterior  part  of  the 
genitals. 

The  diagnosis  between  lesions  of  the  cauda  equina  and  lower  portion  of  the  cord 
is  not  always  possible.  The  prognosis  of  lesions  of  the  cauda  equina  is,  of  course, 
much  better  than  when  the  cord  itself  has  been  injured. 

SPINAL  MENINGES. 


The  cord  is  covered  by  a  continuation  downward  of  the  cerebral  meninges.  It 
has  a  dura  mater,  arachnoid,  and  pia  mater. 

Dura  Mater. — The  outer  or  endosteal  layer  of  the  cerebral  dura  mater  ends 
posteriorly  at  the  edge  of  the  foramen  magnum  but  anteriorly  at  the  third  cervical 
vertebra.  The  inner  or  meningeal  layer  continues  downward  as  a  tough  fibrous  tube 
from  the  foramen  magnum  to  the  second  or  third  sacral  vertebra,  and  thence  is  pro- 
longed downward  as  a  fibrous  cord  (coccygeal  ligament)  to  be  attached  to  the  peri- 
osteum over  the  coccyx.  The  dura  mater  in  the  spine  does  not,  as  in  the  skull,  act 
as  a  periosteum.  The  vertebrae  have  a  separate  periosteum  in  addition.  Between  the 
dura  mater  and  the  bodies  of  the  vertebrae  is  a  somewhat  loose  space  filled  with  fat, 
fibrils  of  connective  tissue,  and  a  venous  plexus.  In  injuries  these  vessels  are  ruptured 
and  bleed  and  give  rise  to  clots;  the  blood,  however,  does  not  get  inside  the  mem- 
branes and  the  effusion  rarely  assumes  a  sufficient  size  to  produce  compression  of  the 
cord.     These  veins  pierce  the  ligamentum  subflavum  and  thus  communicate  with 


THE  VERTEBRAL  COLUMN. 


48s 


the  dorsal  spinal  veins.  The  dura 
mater  is  almost  never  torn  in  in- 
juries even  though  the  cord  may  be 
crushed  (Fig.  487). 

Arachnoid. — The  arachnoid 
of  the  spinal  cord  is  a  stouter  mem- 
brane than  the  cerebral  arachnoid. 
Above  it  is  continuous  with  the  cer- 
ebral arachnoid  at  the  foramen  mag- 
num. Below  it  blends  with  the  dura 
at  about  the  level  of  the  third  sacral 
vertebra.  Thus  it  is  seen  that  while 
the  cord  itself  ends  at  the  lower  bor- 
der of  the  first  lumbar  vertebra  the 
subarachnoid  cavity  is  prolonged 
nearly  or  quite  to  the  third  sacral. 
As  in  the  brain,  the  cavity  between 
the  arachnoid  and  the  dura  above  is 
slight,  the  two  membranes  being 
practically  in  contact,  so  that  there 
is  almost  no  subdural  space.  Be- 
tween the  arachnoid  and  pia,  how- 
ever, there  is  a  considerable  cavity 
which  is  continuous  with  the  same 
space  beneath  the  cerebral  arachnoid. 
It  communicates  with  the  fourth 
ventricle  just  above  the  calamus 
scriptorius  by  the  foramen  of  Ma- 
gendie  in  the  median  line,  and  at  the 
sides  by  the  foramina  of  Key  and 
Retzius,  and  also  by  slits  at  the  de- 
scending horns  of  the  lateral  ventri- 
cles. Hence  it  is  that  the  ventricular 
fluid  can  be  drained  by  a  lumbar 
puncture. 

Through  this  subarachnoid 
space  pass  the  septum  posticum  be- 
hind and  the  ligamenta  denticulata 
on  each  side  from  the  pia  to  the 
dura  mater.  It  is  also  traversed  by 
the  anterior  and  posterior  roots  of 
the  spinal  nerves,  the  former  being  in 
front  and  the  latter  behind  the  liga- 
mentuni  denticulatum.  The  arach- 
noid contains  neither  vessels  nor 
nerves  (Fig.  488). 

Pia  Mater. — The  spinal  pia 
mater  is  thin  and  closely  invests  the 
cord.  It  carries  the  blood-vessels 
of  the  cord  and  sends  prolongations 
posteriorly  to  the  dura  as  the  septum 
posticum,  laterally  as  the  two  liga- 
menta denticulata,  and  also  around 
the  anterior  and  posterior  roots  of 
the  spinal  nerves. 

Spinal  Vessels. — Three  ar- 
teries supply  the  spinal  cord,  an  a7ite- 
rior  spinal  in  the  median  line  of  the 
anterior  surface  and  two  posterior 


Skull 


Pedicles,  cut  ■ 


Medulla 


Pedicles. 


XII  T- 


Pedicles< 


iQ 


^ 


'  Laminae,  cut 


.Transverse 

processes 


-Dural  sheath 


dr- 


-zln 


.  End  of 

dural  sheath 


Posterior 
divisions  of 
sacral  nerves4 


Sheath  of  filum  ■ 


(I«Mj 


End  of  filum 


,  Coccyx 


Fig.  487. — Spinal  cord  enclosed  in  unopened  dural  sheath 
lying  within  vertebral  canal;  neural  arches  completely  removed 
on  right  side,  partially  on  left,  to  expose  dorsal  aspect  of  dura; 
first  and  last  nerves  of  cervical,  thoracic,  lumbar,  and  sacral 
groups  are  indicated  by  Italic  figures;  corresponding  vertebrae 
by  Roman  numerals.     (Piersol.) 


APPLIED    ANATOMY. 


•  Pons 


•  Arachnoid 


Spinal  just  behind  the  posterior  spinal  roots  (Fig.  489).  The  veins  are  more  numer- 
ous. They  consist  of  three  sets  or  plexuses,  one  on  the  cord  in  the  meshes  of  the 
pia  mater,  another  in  the  spinal  canal  between  the  dura  mater  and  the  bone,  and 
the  third  on  and  around  the  outside  of  the  vertebras.  The  veins  on  the  cord 
in  the  anterior  and  posterior  median  fissures  communicate  above  with  the  veins 
of  the  medulla.  The  lateral  veins  empty  through  the  radicular  veins  which  accom- 
pany the  spinal  nerve  roots.  The  veins 
in  the  spinal  canal  form  anterior  and 
posterior  plexuses  between  the  dura 
and  bone  and  communicate  with  the 
extraspinal  plexuses  around  the  laminae 
and  spinous  processes  posteriorly  (dorsi- 
spinal  veins)  and  the  plexus  around 
the  bodies  anteriorly. 

Spinal  Hemorrhage. — Spinal 
hemorrhages,  though  sometimes  caused 
by  disease,  are  usually  the  result  of  in- 
jury. They  frequently  accompany  frac- 
tures and  dislocations.  They  may  be 
either  extradural,  intradural,  or  in  the 
cord — hsematomyelia.  They  exist  either 
coincident  with  the  original  injury  or 
appear  within  a  few  hours. 

Spinal  hemorrhages  are  rarely  large 
and  those  in  the  substance  of  the  cord 
are  the  more  common.  They  are  usu- 
ally venous.  Extradtiral  hemorrhage 
comes  from  the  plexuses  between  the 
dura  and  bone  and  the  clot  may  extend 
through  the  intervertebral  foramina.  It 
is  usually  of  small  extent  and  practically 
does  not  produce  paralysis  from  pressure 
on  the  cord,  hence  operation  for  its 
relief  is  useless.  Jntradural  hemorrhage 
comes  from  the  vessels  of  the  pia  and 
may  invade  not  only  the  subarachnoid 
but  also  the  subdural  space.  It  may 
remain  localized  at  the  site  of  injury 
or  the  blood  may  sink  and  fill  a  con- 
siderable portion  of  the  spinal  canal. 
Owing  to  the  looseness  of  the  cord  in  its 
dural  sheath  the  hemorrhage  spreads 
and  does  not  usually  give  rise  to  pressure 
symptoms,  hence  operation  is  rarely  ad- 
visable. Large  hemorrhage  sometimes  comes  down  from  cerebral  apoplexy  or  injuries. 
Hcsmatomyelia.  —  Hemorrhage  into  the  substance  of  the  cord  may  be  caused  by 
extension  or  accompany  the  contusion  due  to  dislocation  or  fracture.  The  paralysis 
which  follows  serious  injuries  of  the  spine  is  usually  due  to  hemorrhage  into  the  gray 
or  white  matter  of  the  cord.  The  gray  matter  being  the  softer  is  the  more  frequently 
affected,  the  blood  penetrating  it  for  quite  a  distance.  Hemorrhage  into  the  gray 
matter  destroys  it  and  produces  an  incurable  paralysis.  When  into  the  white  matter 
restoration  of  function  through  absorption  may  occur  in  from  four  to  six  weeks.  In 
either  case  operation  usually  is  of  no  service.  The  location  of  the  hemorrhage  will 
be  revealed  by  the  interference  with  the  functions  of  the  cord.  The  hemorrhage  can 
occur  in  the  form  of  a  column  of  blood  infiltrating  the  gray  matter  of  several  seg- 
ments in  one  or  both  directions  from  the  starting-point.  The  longer  extension  is 
usually  toward  the  brain.  It  is  usually  limited  to  one  side  of  the  cord.  Generally  in 
small  and  sometimes  in  large  hemorrhages  the  effect  is  mainly  mechanical,  but  espe- 
cially large  hemorrhages  may  be  surrounded  by  areas  of  softening. 


-^ 


Anterior 
roots  of 
spinal  nerves 


_Dura, 
'  reflected 

Spinal  cord, 
covered  with 

.  arachnoid 

'  and  pia 


Fig.  488.^ — Upper  part  of  spinal  cord  within  dural 
sheath,  which  has  been  opened  and  turned  aside;  ligamenta 
denticulata  and  nerve-roots  are  shown  as  they  pass  out- 
ward to  dura.     (Piersol.) 


THE  VERTEBRAL  COLUMN. 


487 


FUNCTIONS   OF   THE   CORD   AND   SPINAL   LOCALIZATION. 

T\\Q.  direct  or  anterior  pyramidal  tract  is  motor;  the  impulse  coming  from  the 
cerebral  cortex  passes  down  the  spinal  cord  on  the  same  side  and  thence  to  the  ante- 
rior horn  of  the  opposite  side  to  supply  mainly  the  muscles  of  the  arm  and  trunk. 
The  crossed  or  lateral  pyramidal  tract  transmits  motor  impulses  coming  from  the 
cortex  which  cross  in  the  lower  part  of  the  medulla  and  descend  on  the  opposite  side. 
It  supplies  muscles  on  the  same  side  as  that  on  which  the  tract  is.  The  direct  cere- 
bellar tract  conveys  impressions  of  equilibrium.  The  atiterolateral  tract  (ascending 
tract  of  Gowers)  conveys  impressions  of  temperature  and  pain.  The  vestibulospinal 
tract — (descending  tract  of  Lowenthal)  is  an  indirect  motor  path. 

Lissa7ier  s  tract  is  composed  of  ascending  fibres  from  the  posterior  nerve-roots. 
The  posterolateral  (column  of  Burdach)  conveys  common  sensation.  The  postero- 
median (column  of  Goll)  conveys  muscular  sense. 


ANTERIOR 


AMTCRIOn 
UATEBAL 
ARTERIES 


Fig.  489. — Diagram  of  the  spinal  cord  in  the  lower  cervical  region,  with  its  blood-vessels. 

Pyraynidal  Tract. — Motor  paralysis  below,  spastic  condition  of  paralyzed  area, 
exaggerated  reflexes  ;  contractures  ;  degeneration  downward. 

Posterior  Columns. — Sensory  disturbances  ;  ataxia  ;  sensation  of  temperature 
and  pain  diminished  ;  reflexes  abolished  ;  upward  degeneration  of  postero-internal 
column. 

Anterior  Horn. — Motor  paralysis  ;  muscle  atrophy  ;  reflexes  abolished  ;  degen- 
eration descends  and  muscles  show  reaction  of  degeneration. 

Posterior  'Hor7i. — Sensory  disturbances  or  anaesthesia,  such  as  follows  lesion  of 
posterior  column. 

Anterior  Root.  — Same  as  anterior  horn. 

Posterior  Root. — Anaesthesia,  if  complete  ;  hyperalgesia  and  pain  if  irritative. 

Central  Canal. — Painful  and  sensory  impressions  not  properly  recognized,  while 
tactile  or  contact  impressions  are  unaffected  ;  joint  dystrophies. 

One  Lateral  Half. — Brown-S^quard  syndrome  ;  complete  loss  of  power  below  on 
the  same  side  as  lesion  and  slight  loss  of  power  below  on  opposite  side  ;  anaesthesia 
complete  on  opposite  side  below  lesion. 


LESIONS   OF  THE   CORD. 

The  lesions  affecting  priyicipally  the  gray  matter  of  the  cord  are  anterior  polio- 
myelitis, syringomyelia,  progressive  muscular  atrophy,  and  arthritic  muscular  atrophy. 

Anterior  Poliomyelitis. — In  anterior  poliomyelitis  or  infantile  paralysis  the 
lesion  is  mainly  in  the  anterior  horn  and  is  evidenced  by  a  paralysis  of  the  muscles 


488 


APPLIED    ANATOMY. 


solved, 


rophy,  and  the  abolishi 


^  of  the  reflexes.       The  deform ilT^"  seen  are 
secondary  results  of  the  paralysis. 

Syringomyelia  is  an  acquired  enlarg-ement  of  the  central  canal  or  the  formation 
of  new  canals  in  the  gray  matter.  It  produces  motor,  sensory,  and  trophic  disturb- 
ances which  vary  according  to  the  part  of  the  cord  attacked. 

Progressive  Muscular  Atrophy  (Duchenne's  Disease). — The  atrophy  begins 
most  often  in  the  hands  and  extends  to  other  parts  of  the  body.  Then  occurs  an 
atrophy  of  the  gray  substance  of  the  anterior  horns  which  may  extend  to  the  brain  ; 
even  the  white  substance  of  the  direct  and  crossed  pyramidal  tracts  may  also  show 
degeneration.  There  is  a  type  in  which  there  is  a  lack  of  demonstrable  cord  lesions. 
Among  its  various  forms  are  those  called  pseudomuscular  hypertrophy,  progressive 
muscular  dystrophies  (Erb),  and  primitive  progressive  myopathies  (Charcot). 

Arthritic  Muscular  Atrophy. — Disease  of  the  joints  often  results  in  marked 
disturbance  of  the  gray  matter  of  the  cord,  which  in  turn  is  followed  by  muscular 
atrophy  (Church:  Church  and  Peterson,  Nervous  and  Mental  Diseases,  page  38). 

Lesions  Affecting  Principally  the  White  Matter  of  the  Cord. — The  principal 
lesions  affecting  the  white  matter  are  lateral  sclerosis,  locomotor  ataxia,  combined 
posterolateral  sclerosis,  Friedreich's  ataxia,  and  hereditary  spastic  paraplegia. 

Lateral  sclerosis,  or  spastic  paraplegia,  is  almost  unknown  as  a  primary 
affection.  It  is  a  sclerosis  of  the  pyramidal  tracts.  It  occurs  as  a  secondary 
degeneration,  the  result  of  cerebral  disease,  producing  the  spastic  paraplegia  of 
infants — Little's  disease — and  also  follows  transverse  lesions  of  the  spine  from  tumors, 
caries,  fractures,  etc. 

Locomotor  ataxia,  or  tabes  dorsalis,  when  advanced  may  affect  the  entire 
portion  of  the  cord  between  the  posterior  horns  and  the  commissure,  from  the  filum 
terminale  to  the  medulla.  It  begins  in  Clarke's  column  (a  group  of  cells  in  the 
posterior  horn  of  the  cord  extending  from  the  seventh  cervical  to  the  second  lumbar 
nerves)  and  may  involve  the  direct  cerebellar  tracts  and  Govvers's  ascending  antero- 
lateral tracts  and  also  the  posterior  nerve  roots.  It  produces  both  motor  and  sensory 
disturbances  as  well  as  trophic  changes. 

Combined  Posterolateral  Sclerosis — (Ataxic  Paraplegia  of  Cowers). — This 
produces  symptoms  combining  spastic  paraplegia  and  locomotor  ataxia.  The  fol- 
lowing structures  are  affected:  columns  of  Burdach,  GoU,  crossed  pyramidal  tract, 
direct  pyramidal  tract,  and  not  always  the  ascending  tract  of  Gowers. 

Friedreich's  ataxia  (family  or  hereditary  ataxia)  is  a  progressive  paralysis 
often  appearing  through  many  generations.     There  is  a  sclerosis  of  the  columns  of 

GoU  and  Burdach,  crossed  pyramidal  tract,  Gow- 
ers's  tract,  direct  cerebellar  tract,  Lissauer's  tract, 
and  often  atrophy  of  the  cells  of  Clarke's  column. 
Hereditary  Spastic  Paraplegia. — This  is 
a  degeneration  of  the  pyramidal  tracts,  columns  of 
Goll  and  Burdach,  and  direct  cerebellar  tract.  The 
disease  has  been  traced  through  many  generations. 

OPERATIONS  ON   THE  SPINE. 

Spinal  Puncture. — Spinal  puncture  may  be 
performed  either  for  diagnostic  purposes,  for  relief 
of  accumulations  of  subarachnoid  fluid,  or  for  the 
purpose  of  producing  spinal  anaesthesia. 

The  lumbar  region  is  usually  selected  and  the 
puncture  made  in  the  median  line  or  to  one  side  and 
either  above  or  below  the  spine  of  the  fourth  lumbar 
vertebra.  A  line  passing  from  the  highest  point  of 
the  crest  of  one  ilium  to  that  of  the  opposite  side 
passes  through  the  lower  part  of  the  spine  of  the  fourth  lumbar  vertebra.  The  punc- 
ture should  always  be  made  below  the  upper  border  of  the  second  lumbar  vertebra, 
because  the  spinal  cord  extends  down  to  that  point  (Fig.  490).  The  lumbar  spines 
are  nearly  or  quite  horizontal  and  do  not  incline  downward  as  do  those  of  the  cervical 


Fig.  490. — Lumbar  puncture  of  the  spine. 


THE   LOWER   EXTREMITY.  489 

and  dorsal  reg,ions.  The  patient  should  bend  the  body  forward,  as  by  so  doing  the 
space  between  the  vertebrae  posteriorly  is  increased. 

The  needle  used  should  be  from  6.25  cm. (2^  in.)  to  10  cm.  (4  in.)  long,  ac- 
cording to  the  age  and  size  of  the  patient.  It  should  be  introduced  in  the  median 
line  and  pushed  upward.  In  its  entrance  it  pierces  the  muscles,  then  the  ligamentum 
subflavum,  which  passes  from  one  lamina  to  the  other,  and  finally  the  dura  mater  and 
arachnoid.  Failure  is  liable  to  occur  either  from  the  patient  straightening  the  spine 
when  the  puncture  is  made  or  from  failure  to  enter  the  spinal  membranes  owing  to 
pushing  the  dura  in  front  of  the  cannula.  A  needle  enters  more  readily  and  surely 
than  does  a  small  trocar  with  its  cannula.  The  shoulder  formed  by  the  cannula,  partic- 
ularly if  not  well  made,  is  apt  to  push  the  tough  dura  ahead  of  it  instead  of  puncturing. 

Laminectomy, — The  laminae  pass  from  the  transverse  and  articular  processes 
to  the  spinous  processes.  On  each  side  of  the  median  line  the  erector  spinae  muscles 
form  thick  masses  and  the  spinous  processes  lie  in  the  groove  between  them.  Hence, 
in  doing  a  laminectomy,  the  depth  at  which  the  laminae  lie  is  apt  to  be  found  much 
greater  than  is  expected.  An  incision  is  first  made  directly  on  the  spinous  processes 
and  continued  down  on  each  side  to  the  laminae.  With  a  chisel-like  periosteal  ele- 
vator the  attachments  of  the  muscles  and  periosteum  are  detached  from  the  base  of 
the  spinous  processes  and  laminae  as  far  out  as  the  transverse  processes.  The  bleed- 
ing from  the  muscles  is  controlled  by  packing.  The  laminae  may  be  divided  with  a 
saw  inclined  inward  or  the  supraspinous,  interspinous,  and  subflava  ligaments  may  be 
divided,  the  spinous  processes  cut  close  to  their  base  and  removed,  and  finally  the 
laminae  removed  with  bone  forceps.  When  the  laminae  are  removed  the  dura  mater 
is  found  separated  from  the  bone  by  fat  and  connective  tissue.  The  veins  here  en- 
countered may  bleed  freely  but  cease  on  pressure  being  made.  If  necessary  the  dura 
may  be  opened,  in  which  case  the  portion  of  the  body  toward  the  head  may  be  low- 
ered to  prevent  too  great  loss  of  cerebrospinal  fluid.  The  roots  of  the  spinal  nerves 
will  be  found  passing  out  laterally  and  should  if  possible  be  avoided.  If  the  poste- 
rior or  sensory  root  is  divided  it  has  the  same  tendency  to  re-unite  as  do  sensory 
nerves  elsewhere,  but  division  of  the  anterior  root  causes  permanent  motor  paralysis. 
The  dura  and  other  structures  are  then  sutured  without  drainage. 

THE   LOWER   EXTREMITY. 

GENERAL  CONSIDERATIONS. 

The  lower  extremity  is  designed  to  bear  the  weight  of  the  body  and  serve  as  a 
means  of  locomotion. 

It  is  composed  of  a  pelvic  girdle,  thigh,  leg,  and  foot. 

The  pelvic  girdle  serves  as  the  medium  of  connection  of  the  lower  extremity  to 
the  trunk  in  the  same  manner  as  does  the  shoulder-girdle  for  the  upper  extremity. 

We  saw  that  prehension,  characterized  by  mobility,  was  the  distinguishing  feat- 
ure of  the  upper  extremity  and  that  the  shoulder-girdle  was  composed  of  two  bones, 
was  loosely  joined  to  the  trunk,  and  held  the  upper  extremity  out  away  from  it. 

The  lower  extremity  on  the  contrary  has  two  functions,  it  must  bear  the  weight 
of  the  body  and  must  move  this  weight  around  from  place  to  place;  hence  strength  is 
essential  and  a  less  amount  of  mobility  suffices.  To  meet  these  changed  conditions  the 
lower  extremity  differs  in  its  construction  from  the  upper  in  the  following  respects: 

1.  The  pelvic  girdle  is  composed  of  one  bone — the  innominate— instead  of  two. 

2.  It  also  forms  a  part  of  a  complete  bony  ring  instead  of  being  incomplete 
posteriorly. 

3.  It  is  more  firmly  joined  to  the  trunk. 

4.  The  hip-joint  is  placed  closer  to  and  in  more  intimate  relation  with  the  trunk 
than  is  the  shoulder. 

5.  The  bones  of  the  lower  extremity  are  heavier  and  stronger  than  those  of  the 
upper. 

6.  The  joints  are  larger  and  stronger,  but  their  movements  are  not  so  extensive. 

7.  The  muscles  are  coarser  and  their  functions  are  not  so  highly  specialized. 


APPLIED    ANATOMY. 


THE  BONY  PELVIS. 

The  pelvis  is  composed  of  the  pelvic  girdle  on  each  side  (innominate  bones), 
and  the  sacrum  and  coccyx  posteriorly.  It  serves  two  purposes.  It  supports  and 
protects  the  abdominal  and  pelvic  viscera,  and  serves  as  the  connection  between  the 
trunk  and  the  lower  limb.  It  is  divided  into  two  parts — the  false  pelvis,  above  the 
iliopectineal  line,  and  the  true  pelvis,  below  the  iliopectineal  line. 

The  false  pelvis  serves  to  support  the  abdominal  viscera,  as  its  name  indicates, 
like  a  basin.  In  man  it  is  large  and  flaring  because  his  normal  position  is  upright, 
but  in  the  lower  animals,  as  the  quadrupeds,  whose  normal  position  is  horizontal,  it 
is  smaller  and  less  prominent. 

The  true  pelvis  contains  and  protects  the  pelvic  organs  and  also  serves  as  the 
connecting  link  between  the  trunk  above  and  the  extremity  below;  hence,  as  it  has 
a  double  function,  it  has  of  necessity  a  composite  structure.  In  order  to  contain  and 
protect  the  pelvic  viscera  it  is  made  hollow,  and  in  order  to  support  the  weight  of 
the  body  on  the  legs  it  is  made  strong.  The  pelvic  contents  are  not  exposed  to 
injury  to  the  same  extent  as  is  the  brain;  therefore,  instead  of  having  a  complete 
covering  of  bone,  like  the  skull,  the  bony  pelvis  is  merely  a  framework  comprised 
solely  of  those  parts  essential  to  strength. 

The  pelvis  supports  the  trunk  in  two  postures,  the  standing  and  sitting.  In  the 
former  the  weight  is  transmitted  through  the  acetabula,  and  in  the  latter  to  the 
tuberosities  of  the  ischia.  ' 


MECHANISM   OF   THE   PELVIS. 

As  was  pointed  out  by  Henry  Morris  ("The  Anatomy  of  the  Joints  of  Man," 
p.  115),  the  bony  pelvis  is  composed  of  arches.  The  two  main  arches  are  the 
femorosacral  and  the  ischiosacral.  These  are  strengthened  by  subsidiary  arches 
which  join  the  extremities  of  the  main  arches  so  as  to  strengthen  and  fix  them. 


Fig.  491. — The  femorosacral  arch.  The  main  arch 
passes  upward  from  one  hip- joint  to  the  other  through 
the  sacrum :  the  subsidiary  arch  passes  downward  from  one 
hip-joint  to  the  other  through  the  pubes. 


Fig.  492. — The  ischiosacral  arch.  The  main  arch 
passes  upward  from  one  tuberosity  of  the  ischium 
through  the  sacrum  down  to  the  opposite  tuberosity; 
the  subsidiary  arch  passes  forward  from  one  tuber- 
osity of  the  ischium  through  the  pubes  and  back  to  the 
opposite  tuberosity. 


Femorosacral  Arch. — This  arch  extends  from  the  acetabula  on  the  sides  to 
the  sacrum  in  the  middle,  which  is  its  keystone.  The  weight  of  the  body  is  trans- 
mitted downward  through  the  spine  to  the  sacrum,  and  then  through  the  two  sides 
of  the  femorosacral  arch  to  the  heads  of  the  femurs.  For  an  arch  to  be  effective  its 
two  extremities  must  be  firmly  anchored,  so  that  they  do  not  separate  when  pressure 
is  made  on  it.  In  artificial  arches,  as  used  in  bridges,  this  separation  is  guarded 
against  by  a  rod  running  from  one  extremity  to  the  other,  forming  a  chord  of  the 
arc.      In  the  pelvis  this  mechanism  is  impossible,   because  this  "  tie-rod"   would 


THE    BONY   PELVIS. 


491 


infringe  on  the  cavity  of  the  pelvis,  and  it  is  to  obviate  this  that  a  counter  arch  is 
introduced.  This  secondary  arch  is  formed  by  the  rami  and  bodies  of  the  pubic 
bones,  and  passes  anteriorly  from  one  acetabulum  to  the  other  on  the  opposite  side. 
It  is  much  weaker  than  the  primary  arch  (Fig.  491)- 

Ischio-sacral  Arch. — In  sitting,  the  pelvis,  viewed  laterally,  is  in  much  the 
same  position  as  in  standing,  being  in  both  almost  vertical  and  beneath  the  spinal 
column.  The  thighs,  however,  are  horizontal  and  the  bulk  of  the  weight  is  sup- 
ported by  the  tuber  ischii.  From  the  keystone  or  sacrum  the  weight  is  transmitted 
through  the  ilium  and  body  of  the  ischium  to  the  tuberosities  on  each  side.  This 
primary  arch  is  strengthened  by  the  secondary  arch  formed  on  each  side  by  the  ramus 
of  the  ischium  and  the  descending  ramus  and  body  of  the  pubis.  Notice  that  this 
likewise  is  weaker  than  the  primary  arch  (Fig.  492). 


FRACTURES   OF   THE    PELVIS. 

The  flaring  wings  or  alae  of  the  ilium  are  not  infrequently  fractured  by  direct 
violence.  The  line  of  fracture  is  usually  transverse  (Fig.  493).  The  displacement 
is  slight  on  account  of  the  muscular  attachments  of  the  iliacus  muscle  inside  and  the 
glutei  muscles  outside.  The  anterior  third  of  the  crest  of  the  ilium  is  subcutaneous 
and  prominent,  hence  by  manipulating  it  crepitus  can  usually  be  elicited  and  the  diag- 
nosis made.  Recumbency  and  the  support  afforded  by  adhesive  plaster  is  all  the 
treatment  necessary. 

The  more  serious  fractures,  however,  are  those  of  the  true  pelvis.  The  pelvic 
cavity  is  somewhat  heart-shaped;  the  sacrum  projects  anteriorly  and  is  so  strong  that 
it  is  rarely  fractured.  At  or  just  outside  of  the  sacro-iliac  joints  is,  however,  one 
weak  point;  between  the  acetabulum  and  the 
pubes,  through  the  rami  of  the  pubes  and 
ischium  and  thyroid  foramen,  is  another;  and 
at  the  symphysis  is  a  third. 

The  most  frequent  fracture  passes  through 
the  pelvic  ring  twice,  anteriorly  through  the 
rami  of  the  pubis  and  ischium  and  thyroid 
foramen  and  posteriorly  through  or  just  ex- 
ternal to  the  sacro-iliac  joint.  Whenever  a 
fracture  of  the  pelvis  is  suspected,  search  for 
this  fracture.  Examine  the  rami  of  the  pubes. 
Pressure  made  along  Poupart's  ligament  just 
external  to  the  spine  of  the  pubes  will  usually 
reveal  a  tender  spot  and  may  elicit  crepitus. 
A  digital  examination  through  the  rectum  or 
vagina  may  likewise  indicate  the  site  of  the 
fracture.  The  bladder  is  frequently  wounded,  the  rectum  almost  never  and  the 
urethra  rarely. 

The  symphysis,  while  comparatively  a  weak  part  is  rarely  the  site  of  injury.  In 
childbirth  the  attachment  of  the  pubes  to  each  other  becomes  relaxed  and  a  slight 
physiological  separation  occurs. 


Fig.  493. — Diagram  illustrating  fracture  of 
the  pelvis;  one  fracture  is  seen  passing  through 
the  ilium;  the  other  passes  through  the  sacro-iliac 
articulation  posteriorly  and  the  thyroid  foramen 
anteriorly. 


THE   ATTACHMENT   OF   THE   LOWER   EXTREMITIES   TO   THE 

TRUNK. 

The  human  body  usually  occupies  one  of  three  positions:  standing,  sitting,  or 
lying.  The  functions  of  the  lower  extremity  are  to  afford  support  to  the  body  and 
accomplish  locomotion,  therefore  any  disturbance  of  the  normal  relation  of  the  extrem- 
ities to  the  trunk  interferes  with  the  carrying  out  of  those  functions  and  proper  sup- 
port is  not  given  and  locomotion  is  imperfect.  In  such  cases  the  positions  assumed 
in  standing,  sitting,  and  lying  are  abnormal,  often  to  an  extent  sufificient  to  constitute 
serious  deformities,  and  locomotion,  as  in  walking  or  running,  is  seriously  impaired 
or  rendered  impossible. 


492 


APPLIED   ANATOMY. 


The  connection  of  the  lower  extremities  with  the  trunk  is  through  the  means  of 
the  pelvic  girdle  and  spinal  column;  therefore  the  pelvis  and  vertebrae  above  exert  a 
marked  influence  on  the  extremities  below  and  must  be  taken  into  consideration. 
The  normal  upright  position  of  man  is  obtained  by  maintaining  a  proper  balance. 
This  balance  can  be  disturbed  either  anteroposteriorly  or  laterally.  The  lower  limbs 
are  placed  laterally,  one  on  each  side;  this  gives  greater  stability  in  that  direction,  so 
that  when  a  person  falls  it  is  usually  in  a  forward  or  backward  direction  rather  than 
toward  the  side. 

Anteroposterior  Equilibrium. — In  the  upright  position  the  highest  joint  is 
that  between  the  occiput  and  atlas  and  the  lowest  that  of  the  ankle;  to  enable  the 
body  to  be  in  a  state  of  rest,  in  the  upright  position,  with  the  use  of  the  least  amount 


A.  B.  c.  D. 

Fig.  494. — Anteroposterior  equilibrium. 

Fig.  A. — The  body  in  the  erect  position;  the  centre  of  gravity  c  is  about  in  the  upper  lumbar  region;  d-e  is 
the  base  of  support.  The  vertical  line  a-b  through  the  centre  of  gravity  c  passes  through  the  occipito-atloid  joint 
above,  in  front  of  the  sacro-iliac  joint  g.  the  hip-joint  h,  the  knee-joint  i  and  the  ankle-joint  ;'  and  falls  between 
the  points  of  support  d-e,  passing  through  the  astragaloscaphoid  joint.  Hyperextension  of  the  hip  and  knee  is 
prevented  by  ligaments. 

Fig.  B. — When  the  trunk  is  inclined  forward  by  bending  at  the  hip- joint,  the  increased  projection  of  the  head 
and  upper  portion  of  the  trunk  in  front  of  the  centre  of  gravity  is  counterbalanced  by  the  increased  projection 
of  the  hips  and  lower  portion  of  the  trunk  posteriorly.  The  vertical  line  through  the  centre  of  gravity  still  cuts 
the  base  of  support  d-e  and  the  body  remains  in  a  state  of  equilibrium. 

Fig.  C — When  the  body  inclines  backward,  hyperextension  at  the  hip  is  prevented  by  ligaments;  therefore, 
when  the  vertical  line  a-b  through  the  centre  of  gravity  c  falls  beyond  the  base  of  support  d-e,  the  body  is  in  unstable 
equilibrium  and  it  falls. 

Fig.  D. — If  the  body,  as  occurs  in  some  diseases  and  injuries,  is  inclined  so  far  forward  as  to  bring  the  vertical 
line  a-b  through  the  centre  of  gravity  c.  in  front  of  the  base  of  support  d-e,  then  it  is  in  a  state  of  unstable  equilibrium 
and  additional  support  is  used,  in  the  form  of  a  cane,  to  prevent  falling  forward. 

of  muscular  exertion  these  joints  are  placed  almost  vertically  one  above  the  other. 
For  the  same  reason  if  any  part  of  the  skeleton  lies  in  front  of  a  line  joining  the 
condyle  of  the  occiput  with  the  astragalo-scaphoid  joint  it  is  counterbalanced  by  a 
projection  toward  the  opposite  side.  Thus  the  anterior  cur\'e  of  the  cervical  region 
is  followed  by  the  posterior  curve  of  the  dorsal;  the  anterior  of  the  lumbar,  by  the 
posterior  of  the  sacral.  The  hip-joint  has  its  centre  of  motion  slightly  behind  the 
centre  of  gravity  as  has  also  the  knee.  A  vertical  line  through  the  center  of  gravity 
must  fall  within  its  base  of  support.  This  latter  is  formed  by  the  arch  of  the  foot ;  its 
two  ends  are  the  tuberosity  of  the  calcaneum  posteriorly  and  the  head  of  the  first 
metatarsal  bones  anteriorly.  The  body  is  in  the  position  of  greatest  stability  when 
the  centre  of  gravity  is  midway  between  those  two  points,  which  is  when  it  passes 
through  the  astragalo-scaphoid  joint.     As  the  line  of  gravity  passes  from  the  centre  of 


THE    BONY    PELVIS. 


493 


the  arch  toward  the  ends,  equilibrium  becomes  more  unstable  until,  when  it  passes 
beyond  them,  it  is  lost  and  the  body  begins  to  fall.  In  maintaining  a  normal  erect 
posture  hyperextension  of  the  hip-joint  is  prevented  by  the  anterior  or  iliofemoral 
ligament;  hyperextension  of  the  knee  is  prevented  by  the  lateral,  posterior,  and 
crucial  ligaments  (Fig.  494,  A).  The  main  muscular  eflorts  required  are  those  of  the 
muscles  of  the  back  of  the  neck  to  hold  the  head  level,  owing  to  the  head  being 
heavier  anterior  to  the  condyles,  and  the  muscles  of  the  back  of  the  leg  to  prevent 
the  dorsal  flexion  at  the  ankle,  due  to  the  centre  of  gravity  falling  in  front  of  the  ankle- 
joint.  When  a  person  falls  asleep  in  the  erect  posture  the  head  drops  forward  and 
when  a  soldier  is  shot  his  calf  muscles  give  way  and  he  falls  forward  on  his  face. 

Deformities  of  the  spine  affecting  its  curves  have  already  been  alluded  to  (page 
478).  When  the  spine  is  the  part  affected  it  is  usually  the  case  that  the  secondary 
curve  fully  compensates  for  the  increased  primary  one,  hence  there  is  no  necessity 


L 


The  tendino-  and 

iliotrochanteric 

bands 


Iliotibial  band 


•Fig.  49s. — Lateral  equilibrium. 

Fig.  A. — The  body  being  erect,  a  vertical  line  a-b  through  the  centre  of  gravity  c  falls  midway  between  the 
ankles  or  base  of  support  d-e  and  the  body  is  in  stable  equilibrium. 

Fig.  B. — The  trunk  being  inclined  to  the  right,  the  centre  of  gravity  c  is  shifted  to  the  right  and  a  vertical 
line  a-b  through  it  falls  still  within  the  line  of  support  d-e  and  the  upright  position  can  still  be  maintained. 

Fig.  C. — If  the  relative  length  of  the  two  legs  is  altered,  as  by  placing  a  block  beneath  one  of  them,  the  pelvis 
and  upper  portion  of  the  body  inclines  to  the  opposite  side,  until  a  vertical  line  a-b  through  the  centre  of  gravity 
C  falls  beyond  the  extremity  of  the  base  of  support  d-e  and  the  body  is  in  a  position  of  unstable  equilibrium. 

Fig.  D. — The  body  in  a  position  of  rest.  The  weight  is  borne  mainly  on  the  left  leg;  the  right  side  of  the 
pelvis  falls  until  the  iliotrochanteric  and  iliotibial  bands  are  tense,  when  the  position  can  be  maintained  without 
muscular  effort. 

for  any  change  in  the  position  of  the  joints  below,  and  we  find  people  with  marked 
deformities  of  the  spine  who  are  normal  from  the  waist  down  and  who  stand  and 
walk  perfectly  well.  Occasionally  a  case  presents  itself  in  which  the  secondary  curve 
has  not  entirely  compensated  the  primary  one  and  then  the  body  is  bent  at  the  hips 
until  the  centre  of  gravity  is  brought  over  the  base  of  support  (Fig.  494,  B).  If  the 
deformity  throws  the  centre  of  gravity  too  far  back,  by  bending  the  hips  it  will  be 
brought  forward,  but  if  for  any  reason,  such  as  ankylosis,  flexion  is  impossible, 
then  it  cannot  be  corrected  at  the  hip-joint,  and  therefore  in  such  cases  equilib- 
rium is  unstable  and  the  body  falls  (Fig.  494,  C).  If  from  deformity  the  centre  of 
gravity  is  thrown  so  far  forward  as  to  fall  beyond  the  base  of  support  then  a  cane 
or  crutches  is  required  (Fig.  494,  D). 

When  the  hip-joint  is  involved  it  is  never  affected  by  hyperextension  (the  ilio- 
femoral ligament  prevents  that),  but  always  by  flexion.  This  throws  the  centre  of 
gravity  forward;  to  bring  it  back  a  secondary  curve  is  produced  in  the  lumbar 
region,  and  we  have  a  condition  of  lordosis  established;   if  this  is  insufficient  then 


^5^^^^^^^  APPLIED    ANATOMY.  ^^^^^^^™ 

the  knees  may  be  partly  flexed,  and  if  both  are  insufficient  then  artificial  support  or 
crutciies  must  be  used.  This  is  the  reason  why  flexion  is  sought  to  be  avoided  in 
the  treatment  of  coxalgia,  and  why  osteotomy  is  done  when  the  hip  is  ankylosed  in  a 
flexed  position.  Practically  speaking  there  is  no  efficient  compensation  occurring  at 
the  sacro-iliac  joints,  the  pelvis  moving  with  the  lumbar  vertebrae. 

Lateral  Equilibrium. — In  the  upright  position  the  centre  of  gravity  falls  mid- 
way between  the  ankles  of  the  two  feet.  The  fact  of  there  being  two  points  of  support 
adds  to  the  stability,  which  increases  as  the  feet  are  separated.  Hence  it  is  that  falls 
in  an  anteroposterior  direction  are  more  common  than  sideways.  In  standing  the 
weight  is  transmitted  from  the  spine  through  the  femorosacral  arches  (page  490)  to 
the  hip-joint,  thence  downward  through  the  femur  and  leg-bones  to  the  astragalus. 
Here  we  have  to  deal  with  straight  lines  and  angles  rather  than  curves.  The  spine 
is  normally  straight;  the  line  from  the  spine  to  the  hip-joint  is  practically  straight 
(no  bending  being  possible),  and  from  the  hips  to  the  feet  is  likewise  straight,  and 
the  centre  of  gravity  falls  midway  between  the  ankles  (see  Fig.  495,  A). 

The  two  innominate  bones  and  the  sacrum  form  practically  one  solid  bone, 
therefore  the  two  hip-joints  always  maintain  the  same  relative  position  to  each  other. 
When  the  leg  is  completely  extended  there  is  no  lateral  movement  at  the  knee- 
joints.  There  is  a  marked  more  or  less  lateral  movement  in  the  subastragaloid 
joint  which  allows  the  leg  to  be  inclined  to  one  side  without  moving  the  foot. 
From  these  facts  it  is  evident  that  lateral  equilibrium  can  be  disturbed  by  a  deviation 
of  the  spine  above  the  sacrum  to  one  side  (Fig.  495,  B),  and  also  by  anything  that 
affects  the  length  of  either  leg  (Fig.  495,  C).  The  femorosacral  arch  is  rarely  affected, 
the  most  usual  affection  being  sacro-iliac  disease,  or  fracture,  or  relaxation  of  the 
sacro-iliac  joint,  especially  in  pregnancy. 

The  lateral  equilibrium  is  maintained  almost  solely  by  muscular  force  except  when 
a  position  of  rest  is  assumed.  The  hip-joint  is  capable  of  both  abduction  and  adduc- 
tion, and  in  the  erect  position  the  ligaments  on  both  the  upper  and  lower  surfaces  of 
the  joint  are  lax  and  do  not  contribute  any  support.  When,  however,  a  position  of 
rest  is  desired  the  hips  are  moved  laterally  so  that  the  centre  of  gravity  falls  on  one 
leg,  which  is  kept  extended,  the  opposite  hip  then  descends  until  further  adduction 
is  stopped  by  the  ligaments  on  the  top  of  the  hip  of  the  other  side  (Fig.  495,  D). 
These  ligaments  are  the  outer  limb  of  the  iliofemoral  (Y)  ligament  and  the  reinforc- 
ing tendinotrochanteric  band,  an  offshoot  from  the  rectus  tendon,  the  iliotrochanteric 
band,  and  by  the  iliotibial  band  from  the  crest  of  the  ilium  to  the  outer  tuberosity 
of  the  tibia. 

Balance. — For  the  movements  of  the  body  to  be  properly  performed  a  definite 
normal  relation  of  the  parts  to  one  another  must  be  maintained,  whether  the  body  is  in 
a  state  of  motion  or  at  rest.  During  movement  the  position  of  the  bones  is  controlled 
by  the  muscles  ;  when  at  rest,  the  muscles  relax  and  the  position  of  the  bones  is  con- 
trolled by  the  ligaments.  The  weight  of  the  body  acts  as  a  constant  force  pressing 
downward.  For  this  constant  pressure  not  to  do  harm  it  is  nicely  balanced  on  the 
bones  and  ligaments  aided  by  the  muscles.  If  any  one  of  these  three  is  disturbed 
the  balance  is  altered  and  disability  and  ultimate  deformity  results.  A  distortion  of  a 
bone,  as  a  badly  united  fracture,  throws  the  weight  and  muscular  action  too  much 
to  one  side  and  first  the  action  of  the  part  is  impaired  and  then,  if  use  is  persisted 
in,  deformity  increases.  When  a  person  who  is  standing  becomes  tired  they  assume 
a  position  of  rest,  that  is,  their  muscles  relax,  their  joints  are  extended  and  the 
weight  is  borne  on  the  ligaments.  If,  now,  as  in  adolescents,  these  ligaments  are 
weak,  they  give  way.  If  in  the  foot,  flat-foot  results  ;  if  in  the  knees,  then  knock- 
knee  ;  if  in  the  back,  scoliosis  or  lateral  curvature.  If  it  is  the  bones  which  are  the 
primary  cause  of  the  lack  of  proper  balance,  the  surgeon  by  osteotomy,  excisions, 
etc. ,  will  restore  them  to  their  proper  direction.  If  it  is  the  muscles,  as  in  infantile 
and  other  paralyses,  transplantations,  or  the  taking  of  a  tendon  from  the  strong  side 
and  placing  it  on  the  weak  side,  will  be  resorted  to.  If  it  is  mainly  the  ligaments, 
these  will  be  aided  in  their  function  by  the  use  of  apparatus,  while  by  means  of  exer- 
cises the  muscles  are  aided  in  regaining  their  normal  power.  The  conservative  sur- 
gery of  the  extremities  has  as  its  underlying  principle  the  restoration  of  equilibrium 
to  a  part  whose  balance  has  been  disturbed. 


THE    BONY    PELVIS. 


495 


DEVIATIONS   OF  THE    SPINE  ABOVE  THE   SACRUM. 

When,  as  in  lateral  curvature  or  scoliosis,  there  is  a  pathological  curve  developed, 
the  centre  of  gravity  is  shifted  from  the  midline  to  one  side  and  it  falls  nearer  the  foot 
of  the  side  toward  which  the  trunk  is  inclined  (see  Fig.  496,  A).  This  makes  the 
equilibrium  unstable  so  that  to  restore  stability  the  hips  are  inclined  to  the  oppo- 
site side  and  the  centre  of  gravity  is  brought  once  more  midway  between  the  ankles 
(Fig.  496,  B).  This  condition  is  produced  when  there  is  a  single  incomplete  curve  or 
deviation  to  one  side;  if,  however,  the  curve  is  complete  and  again  reaches  the  median 
line,  as  is  often  the  case  in  scoliosis,  then  the  centre  of  gravity  is  not  disturbed  and 
there  is  no  lateral  shifting  of  the  pelvis  (see  Fig.  496,  C).  If  the  primary  curve  is 
accompanied  by  a  secondary  curve,  both  being  complete  and  crossing  the  median 
line,  then  also  there  is  no  shifting  of  the  pelvis  (Fig.  496,  D).  If,  however,  the 
curves  are  so  irregular  as  to  shift  more  of  the  weight  to  one  side  than  the  other, 
then  the  pelvis  shifts  (Fig.  496,  £).     This  causes  the  hip  on  the  side  opposite  to  the 


B. 


c. 


D. 


E. 


Fig.  496. — Deviation  of  the  spine  above  the  sacrum. 


Fig.  A. — If  the  trunk  is  inclined  to  one  side,  a  vertical  line  a-b  through  the  centre  of  gravity  is  shifted  to  c-f, 
and  therefore  falls  outside  of  the  base  of  support  d-e  and  unstable  equilibrium  results. 

Fig.  B. — The  inclining  of  the  trunk  to  the  right  has  been  compensated  by  shifting  the  pelvis  to  the  left,  and 
the  vertical  a-b  through  the  centre  of  gravity  c  falls  within  the  base  of  support  d-e  and  stable  equilibrium  has  again 
been  restored. 

Fig.  C. — If  the  deviation  of  the  lower  part  of  the  trunk  to  the  left  is  counterbalanced  by  a  deviation  of  the 
upper  part  to  the  right  then  the  vertical  a-b  through  the  centre  of  gravity  c  falls  within  the  base  of  support  d-e 
and  the  body  remains  in  stable  equilibrium. 

Fig.  D. — If  a  complete  curve  in  the  lumbar  region  is  compensated  by  a  complete  curve  in  the  dorsal  and 
cervical  regions  above,  then  the  centre  of  gravity  c  is  not  shifted  and  a  vertical  line  through  it  still  falls  within 
the  base  of  support  d-e.  and  the  body  remains  in  stable  equilibrium. 

Fig.  E. — If  the  curves  are  irregular,  shifting  more  of  the  weight  of  the  upper  part  of  the  body  to  the  right, 
the  pelvis  is  shifted  to  the  left  until  the  centre  of  gravity  c  is  again  brought  within  the  base  of  support  d-e  and 
stable  equilibrium  is  again  restored. 


inclination  to  appear  higher  than  the  other,  but  it  is  not  really  so  and  the  pelvis  still 
remains  le\el.  It  is  therefore  evident  that  it  is  unnecessary  and  unwise  to  attempt 
to  correct  the  deformity  by  raising  the  apparently  low  hip  by  a  high  shoe.  All 
these  conditions  occur  in  the  lateral  curvatures  or  scolioses  of  childhood  and  adoles- 
cence as  well  as  the  deviations  which  occur  from  empyema,  sciatica,  Pott's  disease, 
and  other  affections.  A  knowledge  of  the  principles  involved  is  essential  to  com* 
prehending  their  production  and  to  directing  the  exercises  and  applying  the  appa- 
ratus used  in  their  correction. 


496 


APPLIED    ANATOMY. 


DISTORTIONS  ACCOMPANYING  AFFECTIONS  OF  THE  LOWER 

EXTREMITIES. 

The  hip-joint  is  capable  of  flexion,  extension,  adduction,  abduction,  and  rota- 
tion. From  the  hip  to  the  foot  is  a  straight  hue;  it  can  be  shortened  by  disease 
or  injury  of  the  bones  of  the  thigh  or  leg,  and  in  rare  cases  it  can  be  lengthened  by 
disease  at  the  epiphyses  producing  a  more  rapid  growth  than  normal.  It  is  almost 
unknown  for  hyperextension  of  the  hip  to  exist,  because  if  the  femur  is  intact  the  ilio- 
femoral ligament  prevents  it.  If  the  head  is  gone  then  the  upper  end  of  the  femur 
luxates  upward  and  backward.  Rotation  likewise  produces  little  effect  on  the  posi- 
tion of  the  greater  trochanter.  Deformities  due  to  flexion,  abduction,  adduction,  and 
shortening  are  common. 

Increased  Flexion. — Fig.  497,  ^  shows  the  normal  position;  Fig.  497,  ^shows 
hyperflexion  at  the  hip.  The  increased  forward  bend  of  the  pelvis  necessitates  an 
increase  in  the  lumbar  curve  in  order  to  maintain  the  anteroposterior  equilibrium. 


B. 


D. 


Fig.  497. — Distortions  accompanying  affections  of  the  lower  extremity. 

Fig.  A. — Normal  erect  position,  showing  the  normal  inclination  of  the  pelvis  and  normal  relation  of  the 
back  and  buttocks. 

Fig.  B. — The  pelvis  has  been  tilted  forward  and  downward,  being  flexed  on  the  thighs;  this  resvdts  in  an 
increased  hollowing  of  the  back  and  an  increased  protrusion  of  the  buttocks. 

Fig.  C. — The  left  thigh  is  adducted  and  the  right  abducted.  If  the  left  hip  is  ankylosed  in  a  position  of  ad- 
duction, as  shown,  then  the  pelvis  is  tilted  down  on  the  right,  inclining  the  spine  immediately  above  in  the  same 
direction.  This  moves  the  centre  of  gravity  to  the  right,  but  is  compensated  by  a  shifting  of  the  pelvis  to  the 
left,  thus  bringing  the  vertical  through  the  centre  of  gravity  within  the  base  of  support.  If  the  right  hip  is  anky- 
losed in  abduction,  the  same  condition  results.  In  order  to  compensate  for  the  uneven  lengths  of  the  limbs  pro- 
duced by  tilting  the  pelvis,  the  knee  of  the  apparently  lengthened  limb  is  bent. 

Fig.  D. — The  solid  outline  shows  the  position  assumed  when  the  right  leg  is  shorter  than  the  left.  By  placing 
a  block  under  the  short  right  leg  the  pelvis  is  raised  to  a  horizontal  line  and  the  curves  of  the  spine  are  straight- 
ened, as  shown  by  the  dotted  outline. 

Thus  lordosis  is  produced  with  the  accompanying  hollowing  of  the  back  and  projec- 
tion of  the  buttock.  This  is  common  in  coxalgia  and  congenital  luxations  of  the  hip. 
Hyperadduction  and  Hyperabduction. — If  there  is  hyperadduction,  as 
when  one  hip  is  ankylosed  in  a  position  of  adduction,  as  shown  in  the  left  limb  (Fig. 
497)  0>  ^^^  pelvis  is  carried  up  toward  the  left;  to  restore  the  balance  the  spine  is 
inclined  to  the  right.  If,  however,  the  right  limb  is  hyperabducted  or  fixed  in  a 
position  of  abduction,  then  in  assuming  the  upright  posture  the  right  hip  descends 
and  the  spine  is  inclined  toward  the  side  of  the  affected  limb,  as  seen  in  the  right  hip 
of  Fig.  497,  C.     In  treating  these  conditions  the  spine  can  be  brought  straight  by 


THE    BONY    PELVIS. 


497 


raising  the  aMucted  limb,  but  doing  so  will  increase  their  inequality  still  more  and  shift 
the  pelvis  too  far  to  the  left.  For  this  reason  raising  the  shoe  is  not  advisable,  but  an 
osteotomy  and  removal  of  the  adduction  or  abduction  is  the  proper  treatment. 

Effects  of  Shortening  or  Lengthening  of  a  Lower  Extremity. — The 
shortening  of  one  limb  produces  the  same  effect  as  the  lengthening  of  the  opposite  one: 
in  other  words  it  is  the  inequality  of  the  limbs  that  counts.  In  Fig.  497,  D  the  right 
extremity  is  the  shorter;  this  causes  the  pelvis  to  till  to  the  right,  carrying  the  lower 
part  of  the  spine  with  it  and  producing  a  right  convex  curve  which  is  most  marked 
in  the  lumbar  region.  To  restore  the  equilibrium  the  parts  above  are  carried  to  the 
left.  Thus  a  lateral  curvature  is  produced,  which,  contrary  to  those  which  originate 
in  the  spine,  is  accompanied  by  tilting  of  the  pelvis.  In  these  cases  the  deformity 
may  be  great.  If  the  spinal  curvature  extends  high  the  shoulders  may  be  uneven, 
the  hips  are  uneven  in  height  and  one  projects  farther  out  than  the  other,  the  legs 
may  be  visibly  unequal  in  length,  and  there  is  marked  limping  of  gait.  The  remedy 
is  obvious.  The  short  limb  is  to  be  made  equal  to  the  long  one  by  raising  the  shoe 
or  by  other  means. 

MEASUREMENT   OF   THE   LOWER    LIMBS. 

The  ability  to  determine  accurately  the  length  of  the  lower  extremities  is  essen- 
tial to  diagnosis  and  important  in  treatment.  It  is  a  dilificult  thing  to  do  and  requires 
knowledge,  care,  and  practice.      It  may  be  accepted  as  a  fact  that  the  limbs  are  nor- 


B. 


C. 


D. 


Fig.  498. — Measurements  of  the  lower  limbs,  viewed  from  the  front,  a,  left  anterior  sui)erior  spine;  b,  right 
anterior  superior  spine;  c.  left  trochanter;  d,  right  trochanter;  ^,  left  internal  malleolus;  /,  right  internal  malleolus; 
g,  umbilicus;  h,  lower  end  of  median  line. 

Fig.  .4. — The  line  of  the  pelvis  a-b  is  in  its  correct  position  at  a  right  angle  to  the  long  axis  of  the  body  g-A; 
a-e  equals  b-f.  and  g-e  equals  g-f  and  a-c  equals  b-d. 

Fig.  B. — The  limbs  in  this  figure  are  of  equal  length  but  the  pelvis  is  tilted.  The  pelvis  a-b  is  tilted  up  on 
the  left  and  down  on  the  right.  Apparent  shortenmg  of  the  left  leg  is  seen  by  com  paring  g-e  with  g-f.  Actual  measure- 
ment shows  a-e  to  be  a  trifle  longer  than  b-f  and  a-c  longer  than  b-d. 

Fig.  C. — One  leg  shorter  than  the  other,  but  the  pelvis  is  in  the  correct  position.  The  actual  shortening 
found  by  comparing  a-e  with  b-f  corresponds  with  the  apparent  shortening  found  by  comparing  g-e  with  g-f. 

Fig.  D. — Legs  unequal,  pelvis  tilted  down  on  the  side  of  the  short  leg.  The  apparent  lengths  g-e  and  g-f, 
taken  from  the  umbilicus  g.  show  the  legs  apparently  equal,  but  the  distance  b-f  is  longer  than  a-e  and  the  absolute 
or  actual  amount  of  shortening  is  only  to  be  found  by  levelling  the  pelvis  as  in  Fig.  C,  when  the  apparent  and  actual 
amount  of  shortening  will  be  found  to  agree. 


mally  equal  in  length.  It  is  true  that  in  rare  cases  there  may  be  a  slight  inequality, 
but  an  amount  of  inequality  readily  detected  by  measurement  will  usually  produce 
an  unevenness  in  the  gait,  a  slight  limp. 

To  measure  accurately,  bony  landmarks  are  preferable  to  the  soft  parts,  such  as 
the  umbilicus;  these  bony  points  must  be  carefully  identified,  they  must  be  in  their 
normal  position,  and  the  tape-measure  must  be  accurately  applied. 

Measurements  are  usually  taken  either  from  the  umbilicus  or  anterior  superior 
spines  to  the  internal  malleoli.  The  latter  is  the  more  accurate  and  shows  the  actual 
32 


4p^^^^^^^^'  APPLIED    ANATOMY.  ^^^^^^^M 

shortening,  while  the  former  shows  the  apparent  sliorteniny;.  To  identify  the  tip  of 
the  internal  malleolus  is  usually  easy  enough,  but  the  anterior  superior  spine  is  not 
so  evident.  The  anterior  portion  of  the  crest  of  the  ilium  should  be  followed  forward 
until  its  anterior  superior  spine  can  be  distinctly  felt.  In  applying  the  tape  it  is 
better  not  to  rest  it  on  the  superficial  surface  of  the  spine  nearest  the  skin  but  rather 
on  its  inferior  surface  nearest  the  feet.  It  should  be  placed  below  the  spine  and  then 
pushed  firmly  upward  and  backward  against  its  lower  surface.  The  superficial  sur- 
face of  the  anterior  superior  spine  is  often  so  rounded  or  flat  as  to  make  it  an  uncer- 
tain point  to  measure  from.  To  put  the  parts  in  their  normal  position  it  is  necessary 
to  see  that  a  line  joining  the  two  anterior  superior  spines  is  at  a  right  angle  with  the 
long  axis  of  the  body,  otherwise  the  tilting  of  the  pelvis  will  vitiate  the  results. 
Fig.  498,  A,  front  view,  shows  the  normal  relation;  g-  is  the  umbilicus;  g-h,  the 
median  hne;  a,  left  anterior  spine;  b,  right  anterior  spine;  c,  left  trochanter;  d,  right 
trochanter;  e,  left  internal  malleolus;  /,  right  internal  malleolus.  The  line  a  b  is  to 
be  at  right  angles  to  g-h.     Then  a-e  =  b-f  zndg-e  ~g-f- 

Fig.  498,  B  shows  the  effect  of  tilting  of  the  pelvis,  the  legs  being  of  equal  length. 
a-b  instead  of  being  at  right  angles  to  g-h  is  inclined  upward  on  the  left  side  and 
down  on  the  right.  Apparent  shortening  is  seen  by  comparing  g-f  with  g-e. 
Actual  measurement  shows  a-e  to  be  a  trifle  longer  than  b-f.  This  is  accounted  for  by 
the  tilting  causing  b-d  to  approach  each  other  while  a-c  have  separated. 

If  one  hip  is  ankylosed  its  femur  should  be  moved  laterally  until  the  line  joining 
the  two  anterior  superior  spines  is  at  right  angles  to  the  median  line  of  the  body; 
the  opposite  limb  is  then  to  be  abducted  to  a  similar  degree  and  the  measurements 
of  the  two  limbs  can  then  be  compared. 

When  the  legs  are  unequal  and  the  pelvis  is  in  a  correct  position,  the  apparent 
and  actual  measurements  agree  (Fig.  498,  C). 

When  the  legs  are  unequal  the  pelvis  is  tilted  down  on  the  side  of  the  short  leg 
(Fig.  498,  D).  Apparent  length  taken  from  the  umbilicus  shows  the  legs  equal,  but 
the  distance  b-f  will  be  found  to  be  longer  than  a-e.  This  will  not  give  accurately 
the  actual  amount  of  shortening  because  of  the  tilting  of  the  pelvis.  It  can  only 
be  determined  by  levelling  the  pelvis  so  as  to  make  the  distances  a-c  and  b-d  equal. 

The  length  of  the  extremity  below  the  neck:  of  the  femur  can  be  determined  by 
feeling  for  the  tip  of  the  greater  trochanter  on  its  upper  posterior  border  and  measur- 
ing to  the  external  malleolus  and  comparing  with  the  opposite  side, 

WALKING. 

As  locomotion  is  one  of  the  main  functions  of  the  lower  extremity,  derange- 
ments of  this  function  are  to  be  explained  by  a  knowledge  of  the  normal  action  of 
its  mechanism.  The  means  by  which  support  is  accomplished  have  already  been 
explained  in  the  maintenance  of  equilibrium.  Locomotion  embraces  walking,  run- 
ning, jumping,  etc.  Of  these  walking  is  the  fundamental  movement,  and  the  others 
are  only  amplifications  and  modifications  of  it.  In  slow  normal  walking  on  a  level 
surface  the  thigh  moves  on  the  pelvis,  the  leg  on  the  thigh,  the  foot  on  the  leg,  and 
the  toes  on  the  rest  of  the  foot.  These  movements  are  almost  solely  in  an  antero- 
posterior direction,  there  being  almost  no  lateral  or  rotary  movements  ;  these  begin 
only  when  the  actions  become  violent  and  irregular,  such  as  are  necessary  in  running, 
overcoming  obstacles,  etc.  It  is  for  this  reason  that  a  person  may  have  no  limp  when 
walking  slowly,  but  a  very  perceptible  one  when  walking  rapidly.  There  is  always 
a  small  amount  of  lateral  motion  present  which  varies  with  the  individual  and  the  sex. 

As  slow  walking  necessitates  mainly  anteroposterior  motion,  it  can  be  explained 
by  viewing  the  body  laterally. 

In  ordinary  walking  the  body  mclines  forward  5  degrees,  in  fast  walking  10 
degrees,  and  in  running  about  22  degrees  (Weber),  In  walking  (Fig.  499,  A)  the 
body  is  inclined  forward  and  at  the  same  time  one  leg  begins  to  advance  (the  right). 
This  causes  flexion  of  the  left  ankle  and  flexion  of  the  right  hip  (Fig.  499,  i9and  C). 
As  the  right  foot  touches  the  ground  it  extends  and  the  right  knee  flexes  to  avoid 
the  shock  of  impact  (Fig.  499,  Z>),  the  left  knee  begins  to  flex  and  flexes  more  than 
the  right  in  order  for  the  left  foot  to  swing  clear  of  the  ground  while  being  advanced; 


REGION    OF   THE    HIP. 


499 


if  this  was  not  done  it  would  be  necessary  to  raise  the  limb  by  tilting  the  pelvis  up 
on  that  side.  The  left  continues  to  advance  flexed  while  the  right  gradually  extends 
(Fig.  499,  E),  and  finally  when  the  right  is  fully  extended  the  left  is  likewise  fully 
extended  (Fig.  499,  F^  and  strikes  the  ground  with  the  foot  about  at  a  right  angle 
to  the  leg. 

The  object  of  flexion  of  all  three  joints  is,  first,  to  avoid  shock  in  impact,  and, 
secondly,  to  raise  the  free  foot  and  allow  it  to  swing  forward  clear  of  the  ground. 
The  object  of  extension  is  to  push  the  body  forward. 

Part  Played  by  the  Various  Joints. — The  hip-\6\n\.  flexes  to  an  extent  pro- 
portionate to  the  length  of  the  step  (Fig.  499,  A).  If  this  joint  is  put  out  of  use  by 
being  ankylosed,  first,  the  shock  of  impact  is  more  severe,  no  flexion  being  possible; 
second,  the  limb  can  only  be  brought  forward  by  bending  the  pelvis  on  the  opposite 
hip,  and,  to  a  certain  extent,  the  trunk  above  backward;  third,  to  aid  still  more  to 
advance  the  foot  forward  the  pelvis  will  be  rotated  laterally  on  the  opposite  hip. 
This  causes  a  swaying  of  the  trunk  backward  and  forward  and  a  side  swing  or 
waddle  of  the  pelvis.  Fourth,  the  forward  propulsive  force  is  weakened  by  the  loss 
of  the  hip  extensors.  The  knee,  like  the  hip,  lessens  the  shock  of  impact  by  flexing. 
It  raises  .the  foot  clear  of  the  ground  as  it  is  swung  forward,  and  it  aids  propulsion 
by  extension.      If  ankylosed,  shock  is  increased,  onward  propulsive  force  is  lost,  and 


E.  D.  c.  B. 

Fig.  499. — Walking.     Tracings  from  photographs  by  Muybridge. 


it  is  necessary  to  tilt  the  pelvis  upward  in  order  to  raise  the  foot  from  the  ground  and 
allow  it  to  swing  forward.  This  abducts  one  or  both  legs  and  causes  marked  wad- 
dling. The  ankle  also  reduces  shock  and  gives  propulsion  ;  if  ankylosed,  shock  is 
increased  and  propulsion  weakened.  This  is  the  least  necessary  of  the  three  joints 
and  to  substitute  it  artificial  appliances  are  useful,  so  that  in  quiet  walking  limp  may 
be  almost  lacking,  but  violent  and  complicated  movements  are  to  a  large  extent 
impossible.     The  toes,  especially  the  big  toe,  aid  in  propelling  the  body  forward. 

REGION  OF  THE  HIP. 

The  hip  is  that  portion  of  the  body  joining  the  lower  extremity  to  the  trunk. 
It  differs  in  construction  from  the  shoulder,  because  it  is  designed  for  strength  as 
well  as  mobility;  hence  it  is  that  the  bones  are  heavier,  stronger,  with  their  proc- 
esses more  marked,  and  that  the  muscles  also  are  bigger  and  more  powerful.  It  is 
often  the  seat  of  injury  and  disease,  the  bones  being  fractured,  the  joint  luxated, 
and  frequently  affected  with  tuberculosis  and  other  diseases. 


BONES   OF   THE   HIP. 

The  bones  of  the  hip  are  the  innominate  bone  and  femur.  The  innominate  bone 
has  its  shape  determined  by  its  relation  to  the  trunk,  being  adapted  to  support  and 
protect  the  viscera,  while  the  femur  has  its  shape  determined  by  its  relation  to  the 
extremity,  being  in  the  nature  of  a  pole  to  support  it. 

The  innominate  bone  (Figs.  500  and  501)  is  composed  of  the  ilium,  ischium, 
and  pubis.  These  are  united  in  the  acetabulum  by  the  triangular  cartilage  and 
become  ossified  about  the  sixteenth  year.  The  ilium  has  a  crest  which  serves  for 
the  attachment  of  the  transverse  abdominal  muscles.     At  its  anterior  extremity  is 


Soo 


APPLIED    ANATOMY. 


the  anterior  superior  spine,  and  at  its  posterior  extremity  the  posterior  superior 
spine.  Its  large  flat  portion,  called  the  ala,  gives  origin  from  both  its  inner  and 
outer  sides  to  muscles  running  to  the  thigh  below.  The  glutei  muscles  are  attached 
to  its  outer  surface  and  the  iliacus  to  its  inner.      Immediately  below  the  anterior 


Crest 

Dorsum  of  ilium 
Anterior  superior  spine 

Anterior  inferior  spine 

Cotyloid  notch 

Iliopectineal  line 

Horizontal  ramus  of  pubis 

Spine  of  pubis 

Descending  ramus  of  pubis 


Superior  gluteal  line 

Inferior  gluteal  line 

Posterior  superior  spine 

Posterior  inferior  spine 
Greater  sacrosciatic  notch 
Acetabulum 

Spine  of  ischium 
Lesser  sacrosciatic  notch 

•Tuberosity  of  ischium 
Ramus  of  ischium 


Obturator  loramen 
Fig.  soo. — The  innominate  bone,  viewed  from  the  outside. 

superior  spine  is  the  anterior  inferior  spine  ;  to  it  is  attached  the  rectus  femoris 
tendon.  The  ischium  is  below  and  behind  the  acetabulum;  its  tuberosity  gives 
attachment  to  the  hamstring  muscles — biceps  (outer),  semitendinosus,  and  semi- 
membranosus (inner).     Along  the  inner  surface  of  the  ramus  of  the  ischium,  in  a 

Crest 
Ilium  (ala) 

Anterior  superior  spine 
Anterior  inferior  spine 


Greater  sacrosciatic  notch 

Spine  of  ischium 
Lesser  sacrosciatic  notch 

Ischium 

Tuberosity  of  ischium 


Iliopectineal  line 

Horizontal  ramus  of  pubis 

Spine  of  pubis 
Body  of  pubis 
Crest  of  pubis 
Symphysis  of  pubis 

Descending  ramus  of  pubis 


I 


Groove  for  pudic  vessels  and  nerve - 
Obturator  foramen' 

Fig.  501. — The  innominate  bone,  viewed  from  the  inside. 

fibrous  canal  (Alcock's),  run  the  internal  pudic  vessels  and  nerve  on  their  way  to 
the  perineum.  They  lie  4  cm.  (i>^  in.)  from  the  surface.  The  pubis  lies  below 
and  anterior  to  the  acetabulum.  Its  upper  inner  edge  forms  the  iliopectineal 
line,  which  is  continued  back  to  form  the  brim  of  the  true  pelvis.     The  superior  or 


REGION    OF    THE    HIP. 


50: 


horizontal  ramus  goes  to  the  ihum,  while  its  inferior  or  descending  ramus  goes  to  the 
ischium.  The  upper  surface  of  the  superior  ramus  gives  origin  to  the  pectineus 
muscle;  it  is  over  this  muscle  that  femoral  hernia  descends.  The  symphysis  pubis 
is  the  junction  of  the  two  pubic  bones  in  the  median  line.  The  crest  is  the  upper 
anterior  edge  and  gives  attachment  to  the  rectus  and  pyramidal  muscles  (for  muscular 


Nelaton's  line 

Anterior  superior  spine 

Acetabulum 

Tuberosity  oi  ischium 


Fig.  502. — Innominate  bone,  resting  on  its  inner  side,  to  show  the  wedge-shaped  formation  01  its  outer  sur. 
face.  The  apex  of  the  wedge  is  Nelaton's  line,  running  from  the  anterior  superior  spine  to  the  tuberosity  of  the 
ischium;  the  anterior  plane  inclines  downward  and  forward  toward  the  pubis  and  the  posterior  plane  inclines 
downward  and  backward  on  the  ilium. 

attachments  see  Figs.  438  and  439,  page  432).  The  outer  extremity  of  the  crest 
is  the  spine  of  the  pubis.  To  it  is  attached  the  inner  extremity  of  Poupart's  liga- 
ment. The  obturator  foramen,  if  the  body  is  in  an  upright  position,  is  just  below 
and  a  little  anterior  to  the  acetabulum;  it  is  closed  by  a  membrane  which  is  incom- 
plete above  to  give  passage  to  the  obturator  vessels  and  nerve.     The  outer  surface 


Obturator  internus  and  gemelli 


Pyriformis' 

Gluteus  medius 
Greater  trochanter 

Vastus  externus 


Crureus 


Attachment  of  ligamentum  teres 
Edge  of  articular  surface 


Anterior  intertrochanteric  line 


y Lesser  trochanter  and  psoas  muscle 


Fig.  503. — Anterior  view  of  the  upper  end  of  the  femur  with  muscular  attachments. 

of  the  membrane  gives  origin  to  the  obturator  externus  muscle  and  the  inner  surface 
to  the  obturator  internus.  This  latter  passes  out  of  the  pelvis  through  the  lesser 
sacrosciatic  notch  just  below  the  spine  of  the  ischium.  Through  the  greater  sacro- 
sciatic  notch,  above  the  spine,  comes  the  pyriformis  muscle  and  great  sciatic  nerve. 
The  acetabulum  is  located  at  the  junction  of  the  ilium,  ischium,  and  pubis,  and  lies 
a  little  to  the  outer  side  of  the  middle  of  Poupart's  ligament,  with  the  femoral  artery 
passing  nearer  its  inner  than  its  outer  edge.  The  obturator  foramen  is  below  and  a 
little  anterior  to  the  acetabulum  when  the  body  is  upright  and  more  anterior  when  it 


APPLIED    ANATOMY. 

is  horizontal.  The  bottom  of  the  acetabukim  has  a  large  fossa,  to  the  upper  portion 
of  which  is  attached  the  ligamentum  teres,  while  the  lower  portion  contains  a  pad  of 
fat.  This  fossa  opens  by  a  large  notch,  called  the  cotyloid  notch,  on  the  side  toward 
the  obturator  foramen;  therefore  the  bony  socket  is  incomplete  at  this  point. 

O.  H.  AUis  has  pointed  out  that  a  line  passing  from  the  anterior  superior  spine 
to  the  tuberosity,  called  the  Roser-Nelaton  line,  forms  the  apex  of  a  wedge,  the 
ilium  sloping  down  on  one  side  while  the  ischium  and  pubes  pass  down  the  other. 
It  divides  the  innominate  bone  into  two  parts,  an  anterior  plane  and  a  posterior  plane 
(Fig.  502). 

The  femur  has  its  neck  coming  off  from  the  shaft  at  an  upward  angle  of  about 
127  degrees  (125  degrees  to  130  degrees).  The  head  and  neck  do  not  lie  in  the 
same  transverse  plane  as  the  line  joining  the  two  condyles,  but  are  inclined  slightly 
forward  (about  12  degrees).  Therefore  the  neck  passes  upward,  inward,  and  a  little 
forward.  As  the  result  of  deformities  or  disease,  the  inclination  of  the  neck  to  the 
shaft  may  be  reduced,  being  90  degrees  or  less.     This  condition  is  known  as  coxa 


Attachment  of    j^ 
the  ligamentum  teres  ~/,^ 


Edge  of  articular  surface 


Posterior  intertrochanteric  line 


Lesser  trochanter 


Gluteus  medius 
Greater  trochanter 
Quadratus  femoris 


Psoas  and  iliacus 
Pectineus 

Gluteus  maximus 
Vastus  intemus 

Linea  aspera 


Adductor  magnus 
Vastus  externus 
Adductor  brevis 

Adductor  longus 


Fig.  S04. — Posterior  view  of  the  upper  end  of  the  femur  with  muscular  attachments. 


vara.  It  may  be  increased,  constituting  coxa  valga.  The  articular  surface  of  the 
head  forms  slightly  more  than  a  hemisphere  and  has  a  pit  below  and  posterior  to  its 
centre  for  the  attachment  of  the  ligamentum  teres.  At  the  outer  upper  extremity 
of  the  neck  where  it  joins  the  shaft  is  the  greater  trochanter.  Its  tip  or  most  promi- 
nent point  is  toward  its  posterior  surface  and  is  just  about  opposite  the  centre  of  the 
hip-joint.  Downward  and  inward  from  the  greater  trochanter,  on  the  inner  and 
posterior  surface  of  the  shaft,  is  the  lesser  trochanter.  Between  the  trochanters 
anteriorly  and  posteriorly  run  the  intertrochanteric  lines.  The  great  trochanter  and 
the  part  immediately  below  and  posterior  gives  attachment  to  the  three  glutei  mus- 
cles, the  short  rotators  (Fig.  504),  the  pyriformis,  the  obturators,  internus  with 
its  two  gemelli  and  externus,  and  the  quadratus  femoris.  The  lesser  trochanter 
gives  attachment  anteriorly  to  the  psoas  and  the  iliacus  and  immediately  below 
to  the  pectineus. 

The  anterior  intertrochanteric  line  marks  the  lower*attachment  of  the  capsule; 
the  posterior  has  inserted  into  it  the  quadratus  femoris  muscle. 


REGION    OF   THE    HIP. 


503 


Gluteus  minimus 


Gluteus  medius 


Gluteus  maximus  detached  and 
turned  down 


■*  S    ,^Pyriformis 


Obturator  intemus 
GemeDi 

Quadratus  femoris 
Adductor  magnus 


Biceps,  long  head 


Semitendinosus 


Semimembranosus 


Short  head  of  biceps 


V^ 


Fig.  505. — Muscles  of  the  region  of  the  hip. 


MUSCLES   OF   THE   HIP. 


The  muscles  of  the  hip  are  numerous  and  their  action  is  often  intricate:  many 
muscles  are  usually  used  to  produce  a  single  movement.  Some  muscles  not  only 
cross  the  hip-joint  but  another  joint  as  well.  Thus  the  psoas  crosses  the  hip-joint  and 
pelvis  to  reach  the  spine.     The  hamstring  muscles,  the  rectus  femoris,  gracilis,  and 


APPLIED    ANATOMY. 

sartorius  cross  both  the  hip-joint  and  knee-joint,  as  does  practically  the  tensor  fasciae 
femoris  through  its  prolongation,  the  iliotibial  band.  The  movements  of  the  hip  are 
flexion,  extension,  adduction,  abduction,  and  rotation.  Circumduction  is  a  combin- 
ation of  the  first  four  movements. 

Flexion  is  mainly  the  result  of  the  action  of  the  sartorius,  iliacus,  psoas,  rectus 
femoris,  and  pectineus. 

Extension  is  mainly  due  to  the  gluteus  maximus,  medius,  and  minimus,  biceps, 
semitendinosus,  and  semimembranosus. 

Adduction  is  accomplished  by  the  pectineus,  adductor  longus,  brevis,  and 
magnus,  and  to  a  less  extent  by  the  gracilis,  quadratus  femoris,  and  lower  part  of  the 
gluteus  maximus. 

Abduction  in  the  extended  position  is  due  to  the  tensor  fasciae  femoris,  sarto- 
rius, gluteus  medius,  and  gluteus  minimus.      When  flexed  the  short  rotators  also  aid. 

Internal  rotation  is  produced  mainly  by  the  tensor  fascia  femoris  and  the 
anterior  portion  of  the  gluteus  medius  and  minimus;  three  muscles  only.  The  ilio- 
psoas acts  as  a  weak  internal  rotator  if  the  femur  is  in  a  position  of  extreme  external 
rotation. 

External  rotation  is  mainly  due  to  the  short  external  rotators — pyriformis, 
gemelli,  obturators,  quadratus  femoris,  the  adductors,  and  the  posterior  portion  of 
the  three  gluteals.  To  a  slight  extent  the  sartorius,  iliopsoas,  pectineus,  and  biceps 
may  also  aid  at  times. 


V 


SURFACE   ANATOMY. 

The  crest  of  the  ilium  can  be  palpated  in  its  entire  length.  In  very  thin  people 
it  causes  an  elevation  of  the  surface,  but  usually  it  is  marked  by  a  depression.  Its 
anterior  third  is  subcutaneous  and  is  more  easily  seen  and  felt  than  the  posterior  two 
thirds.  A  line  joining  the  highest  point  of  the  crests  passes  through  the  fourth 
lumbar  spine.  A  line  joining  the 
anterior  superior  spines  in  front 
passes  below  the   promontory  of 

the  sacrum.    TYio.  anterior  superior  ^^M-  , Crest  of  ilium 

spine  can  be  readily  felt.      It  lies  -;^^^„/^ 
downward  and  outward  from  the  ^z     ,  s 
umbilicus:  as  has  been  said,  vnediS-'^^r 
urements  are  best  taken  by  press- 
ing  the    tape    against    its    lower 
surface   rather   than   its  subcuta- 
neous one. 

The  posterior  superior  spine^ 
marked  by  a  dimple,  is  best  recog- 
nized by  following  the  crest  of  the 
ilium  to  its  posterior  extremity.  It 
is  opposite  the  middle  of  the  sacro- 
iliac joint  and  the  second  sacral 
spine. 

The  posterior  inferior  spine  is 
4  to  5  cm.  ( I  ^  to  2  in. )  directly 
below  the  posterior  superior  spine. 
The  spine  of  the  ischium,  which 
marks  the  position  of  the  pudic 
and  sciatic  arteries,  is  8  to  lo  cm. 
(3  to  4  in.)  below  the  posterior 
superior  spine  and  the  tuberosity 
of  the  ischium  is  1 2  to  15  cm.  (  5  to 
6  in.  ).  Running  forward  from  the  posterior  inferior  spine  for  a  distance  of  4  to  5  cm. 
(i>^  to  2  in.)  is  the  great  sciatic  notch;  through  it  pass  the  pyriformis  muscle,  gluteal 
artery  and  nerves,  and  sciatic  nerve.  A  line  joining  the  posterior  superior  spine  and 
the  tip  of  the  greater  trochanter  may  be  named  the  posterior  iliotrochanteric  line 


Nelaton's  line 


Anterior  superior  spine 
Tip  of  trochanter 


Tuberosity  of  ischium 


Gluteofemoral  fold 


Fig.  506. — Surface  anatomy  of  the  region  of  the  hip. 


REGION    OF   THE    HIP. 


505 


(iliotrochanteric  line  of  Farabeuf).  It  marks  roughly  the  posterior  edge  of  the  gluteus 
medius  muscle  and  goes  through  the  upper  edge  of  the  gluteus  maximus.  The  gluteal 
artery  and  superior  gluteal  nerves  cross  this  line  at  the  junction  of  the  upper  and 
middle  thirds,  this  being  about  opposite  the  posterior  inferior  spine.  A  line  joining 
the  tuberosity  of  the  ischium  and  tip  of  the  greater  trochanter  may  be  called  the 
ischiob'ochanteric  Ime :  it  is  crossed  at  the  junction  of  its  inner  and  middle  thirds  by 
the  sciatic  nerve. 

The  greater  trochanter  is  marked  by  an  eminence  in  thin  people  and  a  depres- 
sion in  the  plump  and  fat.  Its  anterior  upper  edge  is  crossed  by  the  tendon  of  the 
gluteus  medius  and  cannot  be  readily  outlined.  Its  upper  posterior  extremity  or  tip 
is  readily  distinguished  and  is  the  spot  used  for  measurements.  This  point  is  called 
the  tip  of  the  greater  trochanter  and  must  be  searched  for  posteriorly.  It  is  opposite 
the  centre  of  the  head  of  the  femur  and  is  on  a 
level  with  the  spine  of  the  pubis. 

The  Roser-Nelaton  line  is  one  drawn  from 
the  anterior  superior  spine  to  the  tuberosity  of 
the  ischium.  It  passes  through  the  tip  of  the 
greater  trochanter.  It  is  of  importance  in  frac- 
tures and  dislocations  (Fig.  507). 

Bryant' s  triangle  ( ' '  Bryant's  Surgery ' ' , 
vol.  ii,  p.  412)  is  to  be  drawn  while  the  patient  is 
lying  on  his  back.  One  side  is  a  perpendicular 
let  fall  from  the  anterior  superior  spine  to  the 
table,  the  other  side  is  one  joining  the  anterior 
superior  spine  and  the  tip  of  the  greater  tro- 
chanter, the  base  is  a  line  running  horizontally 
from  the  tip  of  the  greater  trochanter  to  the 
perpendicular  line  (Fig.  507).  If  the  tip  of  the 
trochanter  becomes  elevated,  as  in  fractures  of 
the  neck  of  the  femur,  it  shortens  the  base  of 
the  triangle  on  the  affected  side  as  compared 
with  the  base  of  the  triangle  on  the  sound  side. 

The  anterior  iliotrochanteric  line  may  be 
designated  as  a  line  joining  the  anterior  supe- 
rior spine  and  the  tip  of  the  greater  trochanter. 
In  normal  individuals  it  slopes  downward  and 
backward,  forming  an  iliotrochanteric  angle 
(^  a  c,  Fig.  507)  of  about  30  degrees.  In 
cases  of  fracture  or  luxation  this  angle  becomes 
reduced  as  the  shortening  increases  until  the 
tip  reaches  the  level  of  the  anterior  superior  spine.  A  rough  estimate  of  this  angle 
by  sight  and  palpation  usually  enables  one  to  decide  immediately  as  to  the  presence 
of  shortening  from  fracture  or  luxation  without  the  trouble  of  erecting  Bryant's 
triangle.  The  anterior  iliotrochanteric  line  forms  the  anterior  side  of  Bryant's  triangle 
and  the  anterior  half  of  the  Roser-N6laton  line. 

The  gluteal  cleft  separates  the  buttocks.  In  its  lower  portion  can  be  felt  the 
coccyx.  The  gluteal  {gluteofemoral)  fold  is  formed  mainly  by  the  subcutaneous 
fatty  tissues  and  passes  horizontally  outward  from  the  lower  part  of  the  gluteal  cleft. 
A  shortening  of  the  leg  on  either  side  causes  the  corresponding  fold  to  incline  down- 
ward. It  is  marked  in  extension  and  gradually  lessens  on  flexion  and  disappears 
when  90  degrees  is  reached.  It  is  crossed  obliquely  downward  and  outward  at  about 
its  middle  by  the  lower  edge  of  the  gluteus  maximus.  Its  disappearance  in  coxalgia 
is  caused  by  the  flexion  incident  to  that  affection. 

Ligation  of  the  Gluteal,  Sciatic,  and  Internal  Pudic  Arteries. — To 
Hgate  the  gluteal  artery  incise  the  skin  and  part  the  fibres  of  the  gluteus  maximus  in 
the  upper  two-thirds  of  a  line  joining  the  posterior  superior  spine  and  the  top  of  the 
great  trochanter  (Fig.  508).  Pull  the  lower  edge  of  the  gluteus  medius  up  and  the 
artery  and  superior  gluteal  nerve  will  be  seen  coming  out  between  it  and  the  pyri- 
formis.   To  ligate  the  sciatic  and  internal  pudic  arteries  an  incision  parallel  to  the  one 


Fig.  507. — View  of  the  outer  surface  of  the 
bones  of  the  hip  showing  Roser-Nelaton  line 
(a-d),  Bryant's  triangle  (a  be),  iliotrochanteric 
line,  (a  c)  and  the  iliotrochanteric  angle  (b  a  c). 


5o6 


APPLIED    ANATOMY. 


just  described  but  about  7.5  cm.  (3  in.)  lower  is  made  through  the  gluteus  maximus, 
and  just  below  the  edge  of  the  pyriformis  from  without  inward  will  be  found  the 
great  sciatic  nerve,  lesser  sciatic  nerve,  sciatic  artery,  and  the  internal  pudic  nerve  and 
internal  pudic  artery  crossing  the  spine  of  the  ischium. 

Biirscc. — Covering  the  tuberosity  of  the  ischium  is  a  bursa  which  sometimes 
suppurates  and  forms  a  sinus.  It  can  readily  be  excised.  These  sinuses  are  often 
bilateral. 


Gluteus  maximus 
and  pyriformis 

Gluteus  maximus 

Sciatic  artery 

Sciatic  nerve 


Gluteus  maximus 
and  medius 

Gluteal  artery  and  nerve 
Pyriformis 
Gluteus  maximus 
Internal  pudic  nerve 
Internal  pudic  artery 


Fig.  S08. — Ligation  of  the  gluteal,  internal  pudic,  and  sciatic  arteries. 


THE    HIP-JOINT. 

The  hip-joint,  like  the  shoulder,  is  a  ball-and-socket  joint,  and,  like  it,  moves  in 
all  directions.  The  main  function  of  the  shoulder  is  mobility,  but  the  functions  of 
the  hip  are  mobility  and  support.  To  give  the  necessary  support  and  security,  the 
band-like  ligaments  uniting  the  bones  are  strong  and  the  extent  of  the  movements  is 
restricted.  Macalister  (  "  Text  Book  of  Human  Anatomy, "  p.  179)  points  out  that 
while  the  shoulder  has  118  degrees  of  motion  around  a  sagittal  axis,  abduction  and 
adduction,  the  hip  has  only  90  degrees;  around  a  coronal  axis,  flexion  and  exten- 
sion, the  shoulder  has  170  degrees  and  the  hip  only  140  degrees.  In  the  vertical 
axis  the  shoulder  rotates  90  degrees,  while  the  hip  rotates  only  45  degrees.  In 
the  upright  position  the  centre  of  gravity  falls  in  front  of  the  axis  of  rotation  of  the 
hip-joint. 

The  head  of  the  femur  is  5  cm.  (2  in.)  in  diameter  and  forms  f  of  a  sphere. 
Below  and  behind  its  centre  is  the  depression  for  the  attachment  of  the  ligamentum 
teres.  The  acetabulum  is  much  deeper  than  the  glenoid  cavity  of  the  shoulder-joint 
and  its  depth  is  increased  by  the  cotyloid  ligament  around  its  edge.  This  makes  the 
joint  air-tight  and  holds  the  femur  in  place  by  suction,  hence  it  is  called  by  Allis 
( ' '  An  inquiry  into  the  difficulties  encountered  in  the  reduction  of  dislocations  of  the 
hip,"  Philadelphia,  1896)  the  sucker  ligament.  The  acetabulum  is  incomplete  at  its 
lower  anterior  edge,  forming  the  cotyloid  notch.     The  cotyloid  ligament  bridges 


REGION    OF   THE    HIP. 


507 


over  this  notch,  and  its  deeper  part  loses  its  cartilaginous  cells,  becomes  fibrous,  and 
is  called  the  transverse  ligament. 

Beneath  the  transverse  ligament  pass  vessels,  nerves,  fatty  tissue,  and  the 
extremity  of  the  ligamentum  teres,  which  is  attached  to  the  ischium  just  outside. 

Running  up  in  the  floor  of  the  acetabulum  from  the  cotyloid  notch  is  a  depres- 
sion in  which  is  lodged  the  ligamentum  teres  and  a  pad  of  fat  called  the  Haversian 
gland.  The  ligamentum  teres  is  composed  of  synovial  and  connective  tissue.  It 
is  not  strong  and  ruptures  at  about  14  kilos;  the  small  artery  it  contains  affords 
nourishment  for  itself  alone,  only  a  very  small  amount  of  blood  going  to  the  head  of 
the  femur.  Bland  Sutton  regards  it  as  a  vestigial  structure  and  a  regression  of  the 
pectineus  muscle.  It  is  too  weak  to  add  much  to  the  strength  of  the  joint,  and  the 
view  of  Allis  that  its  function  is  to  distribute  the  synovial  fluid  and  act  as  a  lubri- 


~4 


-Anterior  superior  spine 

Anterior  inferior  spine 
Tendon  of  rectus 

Iliotrochanteric  band 

Iliofemoral  or  Y-Hgament 

Weak  p)oint  between  the  branches 
j^H^    of  the  Y-ligament 

Anterior  intertrochanteric  line 


Weak  point,  bursa  for  iliopsoas         / 

/ 

Pubofemoral  ligament 

Fig.  509. — Anterior  view  of  the  ligaments  of  the  hip-joint. 

eating  agent  is  probably  correct.  The  great  pressure  to  which  the  articulating  sur- 
faces of  the  hip-joint  are  subjected  requires  special  lubrication  and  this  is  furnished  by 
the  ligamentum  teres  and  Haversian  gland. 

Like  other  joints,  the  hip  has  a  capsular  ligament  which  is  strengthened  by 
bands  or  ligaments.  These  ligaments  are  the  iliofemoral,  pubofemoral,  and  ischio- 
femoral. 

Iliofemoral  Ligament  (Bertins'  ligament  or  Y  ligament  of  Bigelow). — This 
is  the  strongest  ligament  in  the  body.  The  single  stem  of  the  Y  ligament  is  attached 
to  the  upper  edge  of  the  rim  of  the  acetabulum  just  below  the  anterior  inferior  spine. 
Its  two  branches  are  attached  below  to  the  anterior  intertrochanteric  line.  Its  upper 
edge  is  reinforced  by  a  band  from  the  ilium  to  the  trochanter,  the  iliotrochanteric 
band,  and  one  from  the  reflected  tendon  of  the  rectus,  the  tendinotrochanteric  band 
(Henry  Morris)  (Fig.  509). 

The  pubofemoral  ligament,  also  called  the  pectineofemoral  ligament,  runs 
outward  into  the  capsule  from  the  horizontal  ramus  of  the  pubes.      It  is  quite  weak. 

Ischiofemoral  Ligament. — Allis  describes  this  ligament  as  follows:  "  It  arises 
from  the  ischial  portion  of  the  rim  of  the  socket  and  sends  its  fibres  to  the  capsule  to 
be  blended  with  them.  As  its  fibres  extend  upward  they  separate  like  two  fingers 
or  terminal  processes,  the  one  extending  forward  to  the  base  of  the  oblique  (pos- 
terior) line,  the  other  running  backward  to  the  digital  fossa  (Fig.  510)." 

It  will  be  observed  that  this  makes  it  a  posterior  Y  ligament  with  a  distinct  bony 
attachment  for  its  two  arms  (like  the  external  lateral  ligament  of  the  elbow — see 


sol 


APPLIED    ANATOMY. 


of  the  two  arms  is  half  way  down  the  posterior  surface  of  the 
neck  of  the  femur. 

Capsular  Ligament. — The  capsule  of  the  joint  is  composed  of  a  thin  sac 
strengthened  by  the  band-like  ligaments  just  described.  Wherever  there  is  no  rein- 
forcing band  the  capsule  is  weak.  The  posterior  and  lower  portion  is  weaker  than 
the  anterior  and  upper  portion.  There  is  a  weak  spot  between  the  arms  of  the  ilio- 
femoral ligament  anteriorly,  a  branch  of  the  circumflex  artery  usually  entering  here. 
Between  the  pubofemoral  and  inner  edge  of  the  iliofemoral  ligament  is  another  weak 
point.  A  bursa  here  separates  the  iliopsoas  from  the  joint  and  often  communicates 
with  the  joint.  A  third  weak  spot  is  on  the  lower  posterior  part  of  the  neck  between 
the  two  branches  of  the  ischiofemoral  ligament  (Fig.  511).      Injections  into  the  joint 


Weak  spot 


Weak  portion  of 
capsule  distended 
by  the  injection 
mass 


Fig.  510. — The  ischiofemoral  or  posteriory- 
ligament.  The  stem  of  the  Y  is  attached  at  the 
base  of  the  tuberosity  of  the  ischium  and  one 
branch  is  seen  going  toward  the  greater  tro- 
chanter and  the  other  toward  the  lesser,  leaving  a 
weak  spot  between  them  half-way  down  the  neck 
of  the  bone. 


Fig.  si  I. — Hip-joint  distended  with  wax;  the 
capsule  ends  posteriorly  half-way  down  the  neck 
and  is  seen  distended  by  the  injection  material  pro- 
truding between  the  two  arms  of  the  ischiofemoral 
ligament. 


protrude  very  markedly  at  this  point.  The  weakest  part  of  the  joint  is  the  lower 
anterior,  below  the  pubofemoral  ligament  and  opposite  the  cotyloid  notch;  the 
strongest  part  is  the  upper  anterior  part. 


DISLOCATIONS   OF   THE   HIP. 

Classification.  —  Dislocations  of  the  hip  are  either  anterior  or  posterior 
(Allis)^  If  the  innominate  bone  is  held  horizontally  it  will  be  seen  that  the  Roser- 
Nelaton  line  from  the  tuberosity  to  the  anterior  superior  spine  passes-  through  the 
acetabulum.  It  forms  the  apex  of  a  wedge  the  two  sides  of  which  pass  down,  one 
anteriorly  and  the  other  posteriorly  (Fig.  512).     Therefore  when  the  head  of  the 


1  Dr.  Oscar 
in  his  Gross  P 
the  Hip,"  Philadelphia,  1896 


ar  H.  Allis  has  given  the  clearest  exposition  of  dislocations  of  the  hip  with  which  we  are  acquainted 
rize  Essay  entitled,  "An  Inquiry  into  the  Difficulties  Encountered  in  the  Reduction  of  Dislocations  of 


REGIOX    OF    THE    HIP. 


509 


femur  leaves  its  socket  it  passes  down  either  anteriorly  or  posteriorly  and  we  have 
either  an  anterior  or  a  posterior  luxation. 

The  attachment  of  the  iliofemoral  ligament  immediately  above  the  acetabulum 
and  of  the  ischiofemoral  directly  below  also  tend  to  prevent  the  head's  emerging  at 
these  places  and  favor  its  going  anteriorly  or  posteriorly.  Anterior  luxations  may  be 
either  low  or  high.     The  primary  luxation  is  a  low  one  into  the  thyroid  foramen. 


Xelaton's  line 

Anterior  superior  spine 

Acetabulum 

Tuberosity  of  ischium 


Fig.  S12. — Innominate  bone,  resting  on  its  inner  side,  to  show  the  wedge-shaped  formation  of  its  outer  sur- 
face. The  apex  of  the  wedge  is  Xelaton's  line,  running  from  the  anterior  superior  spine  to  the  tuberosity  of  the 
ischium;  the  anterior  plane  inclines  downward  and  forward  toward  the  pubis  and  the  posterior  plane  inclines 
downward  and  backward  on  the  ilium. 

• 

If  then  the  thigh  is  rotated  outward  the  head  rises,  and  it  becomes  a  pubic  luxation. 
Posterior  luxations  may  also  be  either  high  or  low.  The  primary  luxation  is  a  low 
one  either  on  the  spine  of  the  ischium  or  in  the  sciatic  notch,  and  by  rotation  of  the 
thigh  inward  it  becomes  a  high  one  on  the  dorsum  of  the  ilium  (Fig.  513).  In  cer- 
tain very  rare  cases  in  which  there  has  been  an 
excessive  amount  of  twisting  the  rotation  is 
extreme  and  a  form  of  dislocation  called  in- 
verted is  produced;  it  will  be  explained  later. 
Mechanism  of  the  Production  of 
Luxations. — The  following  should  be  borne 
in  mind  : 

1.  The  neck  of  the  femur  makes  with  the 
shaft  an  angle  of  approximately  128  degrees. 

2.  In  speaking  of  inward  and  outward  ro- 
tation is  meant  inward  and  outward  rotation 
of  the  shaft  of  the  femur.  Thus  if  the  head 
(and  neck)  is  pointing  inward  and  we  rotate 
the  shaft  inward,  the  head  rotates  outward  pos- 
teriorly. If,  however,  we  rotate  the  shaft  in- 
ward while  the  head  is  pointing  outward  then 
the  head  moves  inward  anteriorly.  Thus  it  is 
seen  that  in  rotating  the  shaft  inward  the  head 
is  moved  inward  or  outward  according  to  its 
original  position. 

3.  That  while  actually  the  axis  of  the 
head  and  neck  does  not  coincide  with  a  line 
drawn  transversely  through  the  condyles, 
but  inclines  forward  at  an  angle  of  10  or  12 
degrees,  nevertheless  for  practical  purposes 
we  may  consider  that   it  does  so   coincide  and   normally  points  directly  inward. 

4.  The  position  of  the  greater  trochanter  can  be  recognized  by  its  being  directly 
above  the  external  condyle,  and  the  position  of  the  head  by  its  being  directly  above 
the  internal  condyle, 

5.  The  muscles  may  be  disregarded  in  the  production  of  luxations,  and  the 
action  of  only  the  bones  and  ligaments  considered. 

6.  A  luxation  results  from  the  capsule  being  made  tense  or  even  ruptured  by  a 
leverage  action  of  the  bones,  and  the  head  then  being  thrust  out  on  the  anterior  or 
posterior  plane. 


Fig.  513. — Diagram  illustrating  the  position 
of  the  head  in  high  and  low  dislocations  on  the  an- 
terior and  posterior  planes. 


5IO 


APPLIED    ANATOMY. 


may 


7.  The  primary  luxation   is   a  low  anterior   or  posterior  one. 
changed  by  subsequent  rotation  of  the  thigh. 

8.  Luxations  may  occur  either  when  the  thigh  is  in  abduction  or  adduction. 
Liixatio7i  by  Abdjictio7i. — If  the  thigh  is  forcibly  abducted  the  adductor  muscles 

rupture  and,  the  abduction  increasing,  the  head  is  raised  out  of  the  socket  by  the 
lever  action  of  the  femur  as  its  neck  strikes  the  rim  of  the  acetabulum  and  its  greater 


Pig.  si 4. — Luxation  of  the  hip  by  indirect  or  leverage  action.  The  shaft  of  the  femur,  from  the  greater 
trochanter  out,  is  the  long  arm  of  the  lever,  the  head  and  neck  form  the  short  arm  and  the  upper  edge  of  the  ace- 
tabulum and  ilium  immediately  above  is  the  fulcrum.  When  the  femur  is  abducted  the  head  is  lifted  out  of  its 
socket  rupturing  the  capsular  ligament. 

trochanter  the  ilium  above.  The  head  and  neck  are  the  short  arm  of  the  lever,  the 
rim  of  the  acetabulum  or  iHum  is  the  fulcrum,  and  the  shaft  and  distal  extremity  of 
the  femur  are  the  long  arm.  The  head  rises  from  the  socket,  ruptures  a  part  at 
least  of  the  capsular  ligament,  and  then  a  thrusting  force  is  added  which  pushes  the 
head  forward,  producing  a  thyroid  luxation  (Fig.  514). 

If  while  the  limb  is  hyperabducted  the  shaft  of  the  femur  is  rotated  out  and  the 


Fig.  515. — Posterior  luxation  of  the  hip  produced  by  rotation  and  direct  thrust.  The  femur  is  seen  to  be 
flexed  on  the  pelvis,  adducted  and  rotated  inward;  a  thrust  in  the  direction  of  the  arrow  then  sends  the  head  out 
of  the  acetabulum  onto  the  posterior  plane. 


limb  brought  straight  down,  parallel  with  that  of  the  opposite  side,  then  likewise  the 
head  may  pass  forward  into  the  thyroid  or  pubic  position.  If  while  the  head  is  on 
the  anterior  plane  the  thigh  is  flexed  and  the  shaft  rotated  inward,  then  the  liead 
follows  around  the  outer  edge  of  the  acetabulum  and  passes  from  a  thyroid  to  a 
dorsal  position,  forming  a  posterior  luxation. 


REGION    OF   THE    HIP. 


511 


Luxation  by  Adduction. — If  the  thigh  is  flexed  and  adducted  the  angle  of  the 
neck  and  shaft  prevents  any  bony  fulcrum  from  forming.  If  now  the  shaft  is  strongly 
rotated  inward  the  iliofemoral  or  Y  ligament  becomes  tense.  It  is  wound  around 
the  neck  of  the  bone  and  acts  as  a  ligamentous^  fulcrum.  The  shaft  revolves  on  its 
long  axis,  and  as  it  turns  inward  the  head  turns  outward  and  presses  against  the 
lower  posterior  part  of  the  capsule,  which  ruptures,  and  a  dorsal  luxation  is  produced. 
A  backward  thrust  in  the  long  axis  of  the  femur  also  favors  the  production  of  the 
luxation  (Fig.  515). 

By  outward  rotation  of  the  shaft  the  head  can  be  conducted  around  the  edge  of 
the  acetabulum  until  it  lies  in  the  thyroid  foramen  on  the  anterior  plane,  thus  changing 
a  primary  dorsal  into  a  secondarj'  thyroid  luxation. 

The  Rent  in  the  Capsule. — The  capsule  ruptures  at  its  lower  anterior  or  pos- 
terior portion  according  to  whether  it  is  primarily  an  anterior  or  a  posterior  luxation. 
If,  however,  the  limb  is  rotated  while  the 
head  is  out  of  its  socket,  as  in  the  produc- 
tion of  a  secondary  position,  then  the  cap- 
sule is  torn  still  further,  but  the  Y  ligament 
is  practically  never  torn  either  when  the 
original  luxation  occurs  or  the  secondary. 

The  rent  in  the  capsule  through  which 
the  head  emerges  has  been  proven  both  by 
Robert  Morris  and  Dr.  Allis  to  be  always 
equal  in  size  to  the  head  of  the  femur 
and  never  a  slit.  Therefore  in  every  case 
there  exists  a  rent  in  the  capsule  large 
enough  to  allow  of  returning  the  head, 
provided  it  is  not  closed  or  obstructed  by 
a  rotation  or  malposition  of  the  limb,  or  by  some  foreign  substance  such  as  torn 
muscle  or  infolding  of  the  capsule. 

Injuries  to  the  Muscles. — When  the  thigh  is  abducted  the  adductor  muscles 
are  made  tense,  and  if  it  is  hyperabducted  they  are  torn  ;  these  overstretched 
muscles,  some  of  which  may  be  ruptured,  are  the  three  adductors,  the  pectineus, 
and  the  gracilis.  If  the  luxation  is  an  anterior  one  the  obturator  externus  will  be 
torn  because  it  arises  from  the  outer  surface  of  the  thyroid  membrane.     If  a  posterior 


Fig.  516. — Showing  the  sciatic  nerve  caught 
around  the  neck  of  the  femur.  (After  an  illustration 
by  Dr.  Allis  in  his  prize  essay  on  the  hip.) 


/^ 


Fig.  517. — Posterior  or  dorsal  luxation  of  the  left  hip  (From  an  original  sketch  by  the  author).     The  shortening  is 
seen  by  comparing  the  position  of  the  knees,  the  thigh  is  adducted  and  rotated  inward. 

one  the  internal  obturator  may  be  injured.  Allis  has  pointed  out  that  when  the 
head  passes  from  one  plane  to  another  it  may  tear  the  obturator  externus,  quadratus 
femoris,  and  upper  fibres  of  the  adductor  magnus.  The  tearing  of  these  muscles 
usually  exerts  but  little  influence  on  the  reduction  of  the  luxation. 

Injuries  to  the  Nerves. — Rarely  the  anterior  crural  nerve  may  be  injured  by 
being  stretched  over  the  head  of  the  femur.  The  sciatic  nerve  has  been  injured, 
and  Allis  has  shown  how,  when  a  dorsal  is  rotated  into  a  thyroid  luxation,  the  sciatic 
nerve  is  likely  to  be  caught  around  the  neck  of  the  femur  (Fig.  516).  This  is  favored 
by  making  a  large  circle  while  circumducting  the  knee,  and  also  by  extending  the 
leg  on  the  thigh,  thus  making  the  nerve  tense  and  causing  it  to  lie  closer  to  the  socket. 


APPLIED    ANATOMY. 


To  detect  this  accident  Allis  advises  that  while  an  assistant  pushes  upward  on  the 
knee  in  the  direction  of  the  long  axis  of  the  femur,  the  surgeon  by  flexing  and 
extending  the  knee  will  find  the  nerve  alternately  made  tense  and  relaxed  in  the 
popliteal  space. 

Signs  of  Luxation. — When  luxated  pos/erwr/y  the  foot  is  inverted  whether  it 
is  a  low  or  high  dorsal.  The  thigh  is  adducted,  bringing  the  knee  of  the  affected  side 
in  front  of  the  sound  one.  The  thigh  is  usually  slightly  flexed.  There  is  shortening, 
and  the  higher  the  position  of  the  head  the  greater  the  shortening  and  the  farther  up 
the  trochanter  is  above  the  Roser-Nelaton  line.  Shortening  is  best  seen  with  the 
thighs  flexed  to  a  right  angle  (Fig.  517). 

When  luxated  anteriorly  the  foot  is  everted  or  almost  straight.  If  it  is  a  low 
thyroid  there  will  be  little  or  no  eversion;  if  it  is  a  pubic  luxation  eversion  will  be  more 

marked.  The  thigh  is  abducted;  this  is 
more  marked  in  the  thyroid  and  less  in 
the  pubic.  The  thigh  is  flexed  in  the 
thyroid  but  may  be  straight  in  the  pubic. 
There  is  no  shortening  but  there  may  be 
a  slight  lengthening  difificult  to  demon- 
strate (Fig.  518). 

Reduction. — As  in  the  shoulder 
there  are  two  methods  of  reducing  a 
dislocated  hip,  the  direct  and  the  indi- 
rect. The  direct  consists  in  placing  the 
head  in  as  favorable  a  position  as  possi- 
ble and  then  directly  pushing  or  pulling 
it  towards  the  socket. 

The  indirect  consists  in  using  the 
thigh  as  a  lever  and  rotating  the  head 
into  place.  These  methods  may  be  used 
in  combination. 

Direct  Method  for  Dorsal  Ltixa- 
tions. — Patient  flat  on  the  floor  on  his 
back.  Flex  the  knee  on  the  thigh,  and 
the  thigh  on  the  abdomen;  this  brings 
the  head  down  from  a  high  position  to 
a  low  one  below  the  acetabulum.  Ad- 
duct  the  thigh  slightly;  this  relaxes  the 
Y  ligament  and  prevents  the  head  catch- 
ing on  the  rim  of  the  acetabulum. 

Grasp  the  ankle  with  one  hand, 
then  place  the  other  hand  or  arm  beneath 
the  bent  knee  and  lift  upward  and  inward 
thus  raising  the  head  over  the  rim  of  the 
acetabulum  into  the  socket.  If  the  head 
does  not  enter  rotate  the  thigh  gently, 
first  out  and  then  in,  lifting  at  the  same  time.  This  rotation  is  to  open  the  rent  in 
the  capsule  to  its  widest  extent.  Too  much  rotation  narrows  the  rent  and  obstructs 
the  entrance  of  the  head.  An  assistant  may  at  the  same  time  endeavor  with  his 
hands  to  push  the  head  up  towards  the  socket. 

Another  way  of  using  the  direct  method  (Stimson)  is  to  place  the  patient 
face  downward  on  a  table  with  the  thigh  flexed  at  a  right  angle .  hanging  over  its 
end.  The  leg  is  then  flexed  at  the  knee  and  pressure  made  directly  downward, 
gently  moving  or  rotating  the  head  from  side  to  side.  This  is  a  safe  and  efficient 
method. 

Direct  Method  for  Anterior  Luxations. — In  pubic  luxations  first  slightly  abduct 
the  thigh  and  rotate  the  shaft  of  the  femur  inward  so  as  to  transform  the  pubic  to  a 
thyroid  luxation.  For  thyroid  luxations  flex  the  knee  to  a  right  angle,  and  then 
flex  the  thigh  on  the  abdomen  to  a  right  angle  or  even  more  and  slightly  abduct 
(Allis).     Then  with  one  hand  grasp  the  ankle  and  with  the  other  hand  or  arm  in  the 


Fig.  518. — Thyroid  luxation  on  the  anterior  plane. 
The  thigh  is  flexed  and  abducted;  the  toes  pointing 
forward.      (From  a  photograph  by  Dr.  Chas.  F.Nassau.) 


REGION    OF   THE    HIP. 


513 


flexure  of  the  knee  lift  up  and  slightly  out,  thus  guiding  the  head  toward  the  socket, 
rotating  a  little  if  necessary  (Fig.  519). 

The  Indirect  or  Lever  Method  for  Dorsal  Luxations. — Flex  the  leg  on  the 
thigh  and  the  thigh  on  the  abdomen  in  a  position  of  adduction.      Then  sweep  the 


<\  'A 


^ 


Fig.  519. — Reduction  of  an  anttrn'r  (thyroid)  luxation  by  the  direct  method.  The  pelvis  is  to  be  held  firmly 
to  the  floor.  The  thigh  is  to  be  flexed,  abducted  (Allis),  and  the  head  lifted  upward  and  outward  as  shown  in  the 
small  cut. 

knee  in  a  small  circle  with  external  rotation,  when  the  knee  reaches  the  point  of 
starting  bring  the  limb  down  straight.  Allis  cautions  against  describing  too  large 
a  circle  with  the  knee  on  account  of  the  liability  of  catching  up  the  sciatic  nerve. 


Fig.  S20. — Reduction  of  a  posterior  (high)  dorsal  luxation  by  the  indirect  (lever)  method  of  circumduction. 
The  thigh  is  flexed  and  adducted;  the  knee  describes  the  circle  shown  by  the  dotted  line  while  the  head  pursues 
the  course  shown  in  the  smaller  cut  to  the  right. 

While  rotating  the  thigh  a  lifting  force  may  be  added,  as  in  the  direct  method.  This 
method  is  practically  circumduction  (Fig.  520). 

The  Indirect  or  Lever  Method  for  Thyroid  Luxatio7is. — Slightly  flex  the  thigh, 
about  to  half  a  right  angle,  and  rotate  outward.  Slightly  abduct  or  adduct  if  nec- 
essary to  relax  the  capsule  before  rotating  outward. 

33 


514 


APPLIED    ANATOMY. 


Reversed  Luxations. — In  certain  few  cases,  either  from  the  peculiar  character 
and  direction  of  the  primary  injury  or  from  an  ordinary  anterior  or  posterior  luxa- 
tion becoming  subsequently  more  widely  displaced,  there  result  what  are  known  as 
reversed  luxations.      They  are  of  two  kinds,  reversed  thyroid  and  reversed  dorsal. 

Reversed  Thyroid. — In  a  thyroid  luxation  the  toes  point  forward  ;  if  now  the  leg 
is  forcibly  twisted  until  the  toes  point  directly  backward  a  reversed  thyroid  is  pro- 
duced (Fig.  521).  In  reducing  it  the  head  must  be  first  rotated  back  to  its  original 
thyroid  position  and  then  reduced  by  the  usual  methods. 

Reversed  Dorsal. — In  a  dorsal  luxation  the  foot  is  inverted  ;  if  now  the  leg  is 
forcibly  twisted  outward  until  the  foot  is  everted,  a  reversed  (or  everted)  dorsal  luxa- 
tion is  produced  (Fig.  522).  To  reduce  it  the  leg  must  be  rotated  inward  until  the 
head  resumes  its  original  position  posteriorly  and  then  it  may  be  reduced  by  the  usual 
dorsal  methods.  In  the  production  of  both  these  reversed  luxations  the  ligaments  are 
torn  still  more  and  the  iliofemoral  ligament  may  even  be  partially  detached  from  its 
insertion  in  the  femur. 

The  Ligamentum  Teres. — In  complete  luxations  the  ligamentum  teres  is 
torn  but  it  is  not  large  enough  to  constitute  an  obstacle  to  reduction. 

Infolding  of  the  Capsule  or  Muscle. — Should  the  capsule  be  torn  from  its 
attachment  to  the  femur,  it  may  prevent  reduction  by  filling  the  socket  and  prevent- 


Fio.  521. — Reversed  thyroid  luxation.     (After  Allis.)         Fig.  522. — Reversed  dorsal  luxation.     (After  Allis.) 

ing  the  entrance  of  the  head.  Fragments  of  muscle  may  act  likewise.  To  clear 
the  socket  Allis  advises  first,  rotation  to  tighten  the  Y  ligament  and  pressing  the 
head  firmly  in  ;  second,  to  rock  the  head  backward  and  forward  and  so  clear  the 
obstructing  material  out. 

To  Release  the  Sciatic  Nerve. — If  the  sciatic  nerve  is  caught  around  the 
neck  of  the  femur  and  cannot  be  otherwise  released,  Allis  advises  extending  the  leg 
and  cutting  down  on  the  nerve  at  the  upper  part  of  the  popliteal  space.  It  is  then 
grasped  and  pulled  taut,  this  releases  it  from  the  neck  and  the  thigh  can  then  be 
flexed  and  the  head  replaced  :  of  course,  if  preferred,  an  incision  can  be  made 
directly  down  on  the  nerve  at  the  hip. 

To  Reduce  a  Dislocation  Complicated  by  Fracture. — To  accomplish  this 
Allis  advises  first  a  trial  of  the  usual  direct  method  of  traction  and  pressure  on  the 
head  and,  if  this  fails,  then  while  the  head  is  held  as  near  to  the  socket  as  possible  by 
an  assistant  the  thigh  is  brought  down  and  traction  is  made  downward. 

Congenital  Luxations  of  the  Hip. — In  congenital  luxations  the  acetabulum 
may  be  shallow,  the  head  deformed,  and  the  neck  somewhat  twisted  on  its  shaft. 
These  luxations  are  usually  posterior. 


REGION   OF   THE   HIP. 


515 


Signs. — There  is  no  eversion,  no  flexion  on  lying  down  in  young  cases,  but 
lordosis  is  seen  on  standing  (Fig.  523)  and  in  old  cases,  also  on  lying  down.  The 
main  point  for  diagnosis  is  shortening.  The  limb  is  shorter,  measured  from  the 
anterior  superior  spine,  and  the  anterior  iliotrochanteric  angle  (page  505)  is  dimin- 
ished or  lost  ;  the  tip  of  the  trochanter  is  above  the  Roser-Nelaton  line,  and  the  base 
of  Bryant's  triangle  is  lessened  or  even  obliterated  on  the  affected  side.  By  careful 
palpation  it  can  be  recognized  that  the  head  is  absent  from 
its  normal  position  beneath  the  femoral  artery.  Frequently 
the  top  of  the  trochanter  is  on  a  level  with  the  anterior 
superior  spine.  The  use  of  the  X-ray  is  necessary  to  ascer- 
tain accurately  the  position  of  the  head  and  as  to  whether 
or  not  the  bones  possess  their  normal  shape. 

Rcdndion.  —  As  the  head  is  usually  more  or  less 
fixed  in  its  abnormal  position,  force  has  to  be  used  to 
replace  it.  Paci  of  Pisa  was  the  first  to  reduce  them  sys- 
tematically by  a  modification  of  the  circumduction  method. 
He  flexed  the  thigh  on  the  abdomen,  then  firmly  abducted, 
rotating  outward,  and  used  the  edge  of  the  table  as  a 
fulcrum. 

Lorenz  used  Konig's  padded,  wedge-shaped  block 
under  the  trochanter  as  a  fulcrum  to  pry  the  head  forward. 

The  writer  combined  the  direct  and  indirect  methods 
by  placing  the  child  face  down  on  a  table  with  the  affected 
hip  on  a  sand  pillow  and  the  leg  and  thigh  hanging  over 
the  side.  The  operator  or  an  assistant  then  raises  (flexes) 
the  knee,  bringing  it  toward  the  patient's  axilla,  while  the 
operator  presses  with  his  hands  and  body-weight  down  on 
the  trochanter.  By  gradually  raising  the  knee  and  keeping 
it  close  to  the  body  and  pushing  the  head  forward  it  eventu- 
ally slips  from  the  posterior  to  the  anterior  plane  and  into 
place  (Fig  524).  When  the  head  has  been  brought  onto 
the  anterior  plane  it  is  usually  impossible  to  extend  the 
knee,  on  account  of  tension  of  the  hamstring  muscles,   as  pointed  out  by  Lorenz. 

After  being  reduced  the  thigh  cannot  be  brought  down  at  once  to  its  normal 
position,  as  by  so  doing   the   head   jumps   out   of   its    socket ;   so   it   is   put   up 

in  plaster  of  Paris  in  an  abducted  posi- 
"^■■P^        v^^^^M^^HMj  |.Jqj^  ^qj.  gQj^g  time  and  brought  down 

T^^^^^         ^^^^^^^^^^B  Hip-Disease  (Coxitis  or  Cox- 

^^^^^^k         ^'^^^^^^^^^^^  ^Igi^)- — Disease  of  the  hip  in        early 

^^^^^^H|k  ^^^BHH|H  stage  is  characterized  by  pain,  limitation 

^^^^^^^H|^  V.-**-  ^^^^         ^  of  motion,  and  limping.      The  pain  is 

^^^^^^P^^^  either  a  local  one  in  the  hip  itself  or  a 

^^^Hr       jt  referred  one.     The  hip  is  supplied  by 

m^^      Z^^^**.,*.^  *^"        branches  of  the  anterior  crural,  sciatic, 

^  and  obturator  nerves,  and  as  these  also 

supply  the  region  of  the  knee,  disease 
of  the  hip  causes  pains  to  be  felt  around 
the  knee,  most  often  on  its  inner  side. 
In  an  early  stage  the  limitation  of 
motion  is  due  to  muscular  contraction 
and  it  disappears  under  anaesthesia.  The 
limb  is  held  in  a  position  of  flexion,  ab- 
duction, and  slight  external  rotation.  The  joint  is  more  or  less  rigid.  The  loss  of 
motion  is  only  complete  in  extreme  cases.  In  mild  cases  the  limitation  is  only  pres- 
ent as  a  reduction  in  the  normal  extent  of  movements,  the  joint  may  move  freely  and 
without  constraint  over  a  limited  arc.  The  abnormal  changes  produced  are  to  be 
recognized  by  careful  inspection,  measurements,  and  comparison  with  the  opposite 
healthy  limb. 


Fig.  523. — Child  with  con- 
genital luxation  of  hips,  show- 
ing characteristic  lordosis. 


Fig.  524. — -Author's  method  of  reducing  congenital  lux- 
ation of  the  hip. 


516 


APPLIED    ANATOMY. 


Attitude.— Ow'mg  to  the  pain  in  the  affected  Hmb  the  weight  of  the  body  is 
borne  mainly  on  the  healthy  limb.  Viewing  the  patient  anteriorly  in  an  early  case 
of  the  disease  the  external  rotation  is  readily  seen  in  the  eversion  of  the  foot.  If  the 
foot  itself  is  normal,  rotation  takes  place  at  the  hip-joint  and  not  at  the  knee  or 
ankle  ;  therefore  a  foot  that  is  abnormally  turned  out  indicates  that  there  is  some- 
thing in  the  hip  to  cause  it  to  turn  out.  The  affected  limb  is  seen  to  be  held  in  a 
position  of  abduction,  out  away  from  the  healthy  one.  The  flexion  is  evidenced  by 
the  affected  limb  being  placed  a  litde  in  advance  of  the  other  and  bv  the  bending  at 
the  groin.  If  the  feet  are  placed  together  there  may  also  be  flexion  of  the  knee 
(Fig.  525). 

Tilting  of  the  pelvis  may  or  may  not  be  apparent,  but  it  exists  and  can  be  dem- 
onstrated by  a  careful  examinadon.  Viewed  posteriorly,  besides  the  position  of  the 
limb  as  seen  from  in  front,  there  is  in  addition  a  change  in  the  gluteal  folds  and 

buttock.  The  gluteal  fold  on  the  affected  side  is 
lowered  in  position  and  shorter  than  on  the  healthy 
side  and  the  buttock  is  flattened.  The  flattening  of 
the  buttock  is  caused  by  the  flexion  of  the  hip.  This 
flexion  likewise  tends  to  obliterate  the  gluteal  fold. 
The  difference  in  height  of  the  gluteal  folds  is  caused 
by  the  tilting  down  of  the  pelvis  on  the  affected  side. 
An  inequality  in  the  lower  limbs,  whether  due  to 
shortening  or  to  malposition,  such  as  flexion,  will 
be  visible  at  once  by  an  inequality  of  the  gluteal 
folds,  one  being  higher  than  the  other.  Flexion 
deformity  is  recognized  when  the  patient  is  standing 
by  the  bending  at  the  hip-joint  and  by  the  lordosis 
or  hollowing  of  the  back.  When  the  patient  is  re- 
cumbent on  a  flat  surface  and  both  legs  are  brought 
straight  down  so  that  both  knees  are  in  contact  with 
the  table,  then  if  flexion  is  present  it  causes  the  lum- 
bar vertebrae  to  arch  and  the  back  to  rise  from  the 
table.  If  now  the  thigh  of  the  affected  side  is  ele- 
vated until  the  back  again  touches  the  table  the  de- 
gree of  elevation  necessary  to  accomplish  this  will 
be  the  measure  of  flexion. 

Measuremaits. — The  child  being  flat  on  its 
back  the  pelvis  is  to  be  made  level  by  seeing  that 
a  line  joining  the  two  anterior  spines  is  at  right 
angles  to  the  median  line.  If  abduction  is  present 
the  limb  points  away  from  the  median  line.  It  can- 
not be  brought  straight  down  parallel  with  the 
sound  leg  without  tilting  the  pelvis.  If  measured 
from  the  umbilicus  to  the  internal  malleolus  the 
affected  leg  measures  more  than  the  sound  one. 
This  is  called  apparent  lengthening.  If  when  both 
limbs  are  placed  in  the  same  degree  of  abduction 
and  are  measured  from  the  anterior  spine  to  the  internal  malleolus  they  measure 
the  same,  there  is  no  real  shortening. 

In  advanced  disease  adduction  is  more  common  than  abduction.  This  produces 
an  apparent  shortening,  as  shown  by  measurement  from  the  umbilicus  to  the  internal 
malleolus  ;  if  the  sound  limb  is  placed  in  the  same  degree  of  adduction  as  the  affected 
one,  the  distances  from  the  anterior  spines  will  show  no  actual  shortening  unless  there 
is  a  loss  of  bone  or  displacement  at  the  hip-joint.  The  pelvis,  instead  of  being 
tilted  down  on  the  diseased  side,  is  tilted  up.  Flexion  is  usually  more  marked  and 
the  foot  is  usually  inverted  instead  of  everted. 

Hip-Abscess. — Tuberculosis  of  .the  hip  probably  begins  in  the  neighborhood 
of  the  epiphyseal  line  of  the  femur  and  involves  the  joint  secondarily.  The  epiph- 
ysis of  the  head  begins  above  near  the  edge  of  the  articular  cartilage  and  runs 
obliquely  across  upward  and  inward-     It  is  thus  entirely  within  the  capsule  and  when 


Fig.  525. — Early  stage  of  coxalgia, 
showing  the  affected  left  limb  abducted, 
thus  lowering  the  pelvis  on  that  side; 
slightly  flexed,  thus  obliterating  the  glu- 
teofemoral  fold,  and  slightly  everted. 


REGION    OF   THE    HIP. 


517 


pus  forms  it  first  perforates  the  articular  cartilage  and  enters  the  joint  and  then 
perforates  the  capsule  to  point  externally.  There  are  three  favorite  places  of  exit, 
viz. :  ( I )  on  the  posterior  surface  of  the  neck  between  the  branches  of  the  ischio- 
femoral ligament;  (2)  on  the  lower  anterior  surface  beneath  the  iliopsoas  tendon,  be- 
tween the  pubofemoral  and  iliofemoral  ligaments,  through  the  bursa  found  here 
which  may  communicate  with  the  joint  ;  and  (3)  at  the  cotyloid  notch. 

The  head  and  neck  of  the  femur  and  also  the  acetabulum  become  carious.  Pus 
may  find  an  exit  at  other  places  besides  those  mentioned.  It  may  perforate  the  ace- 
tabulum and  show  above  Poupart's  ligament  at  its  outer  side,  or  may  break  through 
the  upper  posterior  portion  of  the  capsule.  Not  often  does  it  break  through  between 
the  branches  of  the  iliofemoral  ligament.  When  it  does  break  through  anteriorly  it 
points  in  Scarpa's  triangle,  commonly  to  the  in- 
side of  the  vessels;  when  it  breaks  through  pos-  ,-——-. 
teriorly  it  descends  beneath  the  fascia  lata  and 
points  on  the  posterior  or  outer  portion  of  the 
thigh. 

Coxa  Vara. — The  normal  angle  which  the 
head  and  neck  make  with  the  femoral  shaft  may 
vary  according  to  Humphry  {Jour.  Atiat.  and 
Phys. ,  xxiii,  236)  from  1 10  to  140  degrees.  Some- 
times as  a  result  of  injury  or  disease  the  neck 
makes  a  more  acute  angle  than  normal,  coming 
off  at  an  angle,  of  90  degrees  or  less.  This  is 
called  coxa  vara  (Fig.  526).  In  some  cases  it  is 
due  to  a  bending  of  the  neck  caused  by  soften- 
ing of  the  bone,  as  in  rachitic  affections,  or  to 
fracture.  The  limb  is  shortened,  the  trochanter 
raised  above  the  Roser-Nelaton  line,  and  abduc- 
tion and  flexion  are  restricted.  To  rectify  it 
Whitman's  operation  of  wedge-shaped  resection 
is  done.  A  wedge  of  bone  with  a  base  of  2  cm. 
(^  in. ),  apex  inward,  is  removed  at  a  point  op- 
posite the  lesser  trochanter.  The  femur  is  then 
placed  in  abduction  and  the  bone  allowed  to  heal. 
When  the  limb  is  brought  down  the  angle  of  the 
head  and  neck  will  be  much  increased  and  the 
deformity  and  disability  will  have  been  removed. 

Coxa  Valga. — The  term  coxa  valga  has 
been  applied  to  the  opposite  condition,  when  the 

neck  is  nearly  parallel  with  the  shaft  ;  it  is  rarer  and  of  less  importance  than  is  coxa 
vara.  Orthopaedists  regard  135  degrees  as  the  normal  limit  of  the  angle  between  the 
neck  and  shaft  of  the  femur,  but  Humphry  placed  it  at  140  degrees. 


Fig.  S26. — Normal  angle  of  the  head  and 
neck  to  the  shaft  of  the  femur  with  the  altera- 
tion in  position  in  coxa  valga  and  coxa  vara 
shown  by  dotted  lines. 


OPERATIONS    ON   THE   HIP-JOINT. 

The  operations  on  the  hip  are  usually  done  either  for  hip-disease  or  congenital 
luxations.  More  rarely  traumatic  or  pathological  luxations  or  intracapsular  fractures 
may  be  operated  on.  The  joint  may  be  approached  either  anteriorly  or  laterally. 
Lateral  operations  are  the  more  mutilating,  while  anterior  ones  are  often  sufficient 
and  less  serious. 

Lateral  Operations. — In  approaching  the  joint  from  the  side  the  incision  of 
Langenbeck  is  preferred.  It  begins  well  up  on  the  buttocks  on  a  line*  with  the  pos- 
terior superior  spine  (page  500)  and  is  continued  down  over  the  great  trochanter  in 
the  axis  of  the  thigh.  If  made  with  the  limb  flexed  the  line  of  incision  will  be 
straight.  The  muscular  fibres  and  tendon  of  the  gluteus  maximus  are  cut  in  the  line 
of  the  incision.  This  exposes  the  posterior  edge  of  the  gluteus  medius,  which  is  to 
be  pulled  forward,  and  the  pyriformis,  which  is  to  be  drawn  backward  or  loosened 
from  its  insertion  into  the  trochanter.  The  capsule  can  then  be  incised  and  the  joint 
examined.      Further  exposure  may  be  obtained  by  loosening  the  gluteus  medius  and 


5i8 


APPLIED    ANATOxMY. 


gluteus  minimus  from  their  insertion  in  the  top  of  the  trochanter  and  pushing  them 
forward.  The  Hgamentum  teres  is  often  destroyed  by  the  disease.  Removal  of  the 
head  of  the  femur  enables  the  acetabulum  to  be  examined  and  carious  bone  curetted 
away  if  necessary.  The  incision  through  the  gluteus  maximus  muscle  will  be  almost 
parallel  to  its  fibres  and  near  its  anterior  edge.  Care  is  to  be  taken  not  to  go  too 
high  up  between  the  pyriformis  and  gluteus  medius  because  the  main  trunks  of  the 
gluteal  artery  and  superior  gluteal  nerve  make  their  exit  there  from  the  great  sacro- 
sciatic  notch.  The  principal  bleeding  will  come  from  branches  of  the  gluteal  artery 
descending  from  that  point.  This  operation  is  practically  limited  to  cases  of  exten- 
sive caries  in  which  it  is  desired  to  do  a  radical  operation  (Fig.  527). 

Boeckmann,  of  St.  Louis,  made  a  large  horseshoe-shaped  flap  over  the  greater 
trochanter.  Its  base  was  upward  and  it  consisted  of  skin  and  superficial  fascia.  This 
flap  was  raised  and  a  chain-saw  passed  underneath  the  muscles  inserting  into  the  top 


Gluteus  maximus 

Gluteus  medius 

Head  of  femur 
Greater  trochanter 

Gemelli 

Obturator  intemus 
Quadratus  femoris 


Posterior  superior  spine 


Branches  of  gluteal  artery 


Outer  surface  of 
acetabulum 

Branches  of  sciatic  artery 

Pyriformis 

Sciatic  nerve 

Gluteus  maximus 


Fig.  527. — The  lateral  mode  of  approach  in  operating  on  the  hip- joint;  large  incision  made  to  show  relation  of  the 

parts  involved. 

of  the  greater  trochanter,  and  the  latter  was  then  sawed  off  and  turned  up  as  a 
flap.  This  exposed  the  upper  surface  of  the  head  and  neck  of  the  femur.  The 
operation  was  done  for  intracapsular  fracture,  the  fragments  being  pinned  together 
with  ivory  pegs  and  the  trochanter  brought  down  and  again  fastened  in  place  with 
ivory  pegs.  The  skin-flap  was  also  brought  down  and  sutured.  While  good  ex- 
posure can  be"  obtained  by  this  method,  it  is  almost  too  severe  and  has  not  been 
generally  adopted. 

Lorenz,  in  congenital  luxations,  incised  from  the  anterior  superior  spine  down 
and  out  toward  the  trochanter.  The  tensor  fasciae  femoris  is  pushed  forward  and 
the  glutei  muscles  backward.  Hoffa  modified  this  operation  by  making  his  incision 
along  the  anterior  edge  of  the  greater  trochanter.  As  the  hip-joint  is  nearer  the 
anterior  than  the  lateral  surface  of  the  body  we  believe  it  to  be  better  to  approach  it 
from  the  front  rather  than  from  the  side. 


THE   THIGH. 


519 


Anterior  Operations. — Liicke  made  an  incision  from  just  below  the  anterior 
superior  spine  running  downward  and  inward  along  the  inner  margin  of  the  sar- 
torius.  The  sartorius  and  rectus  muscles  were  displaced  outward  and  the  iliopsoas 
inward. 

Hiiter,  Parker,  and  Barker  made  the  incision  directly  downward  from  the  anterior 
superior  spine  and  pulled  the  sartorius  and  rectus  inward  and  the  tensor  fasciae 
femoris  and  gluteus  medius  and  minimus  outward  (Fig.  528). 

The  method  of  Hiiter,  Parker,  and  Barker,  is  not  difficult.  The  only  vessel 
encountered  is  a  branch  of  the  external  circumflex.  One  should  not  go  too  low, 
or  some  muscular  branches  of  nerves  going  to  the  vastus  externus  will  be  wounded. 
No  muscles  are  divided.  The  writer  has  Used  this  method  with  satisfaction  in  cases 
of  hip  disease  and  intracapsular  fracture. 

If  additional  room  is  desired  the  fascia  lata  may  be  divided  laterally  and  the 
tensor  fasciae  femoris  and  gluteus  medius  muscles  may  be  detached  from  the  spine 
of  the  ilium  and  back  along  the  crest,  as  done  by  Codivilla.  They  are  to  be  again 
sewed  back  into  place  before  closing  the  wound. 

Inferior  Operations. — Ludlof,  in  congenital  luxations,  abducted  the  thigh  to 
a  right  angle  and  made  his  incision  along  the  tendon  of  the  adductor  longus.      This 

Sartorius 

Rectus 

Anterior  inferior  spine 

Anterior  superior 
spine 

Head  of  femur 

Tensor  fascia 
femoris 


Small  branches  of 
deep  external  cir- 
cumflex artery  and 
nerves 
Vastus  externus 


Gluteus  medius 
Gluteus 


Neck  of  femur 


Fig.   S28. — Anterior  operation  on  the  hip-joint. 

muscle  was  then  drawn  downward  and  the  pectineus  upward  and  the  joint  exposed. 
The  writer  prefers  to  make  an  incision  along  the  inner  side  of  the  femoral  vein.  The 
vessels  are  then  to  be  drawn  upward  and  outward  and  the  pectineus  downward  and 
inward  and  the  capsule  is  at  once  evident. 

THE  THIGH. 


STRUCTURE. 

The  thigh  is  composed  of  the  femur  imbedded  in  three  main  sets  of  muscles, 
and  is  supplied  and  traversed  by  the  femoral  vessels  and  sciatic  and  anterior  crural 
nerves. 

The  femur  serves  as  a  support  and  keeps  the  knee  out  away  from  the  trunk. 

The  muscles  move  the  thigh  on  the  trunk,  or  vice  versa,  and  the  leg  on  the 
thigh. 

The  blood-vessels  and  nerves  not  only  supply  the  structures  of  the  thigh  itself, 
but  also  serve  as  channels  for  the  transmission  of  blood  and  nervous  impulses  to  and 
from  the  parts  beyond,  hence  their  large  size. 


S20 


APPLIED    ANATOMY. 


MUSCLES    OF   THE   THIGH. 

There  are  three  main  sets  of  thigh  muscles,  viz. :  extensors,  flexors,  and  adduc- 
tors.     We  will  limit  our  consideration  to  the  long  muscles. 

Extensor  Muscles. — The  extensor  muscles  consist  of  the  quadriceps  extensor, 

composed  of  the  rectus  femoris,  vastus 
iuternus,  vastus  externus  and  crureus 
{vastus  intermcdius),  and  we  might  add 
also  the  sartorius.  The  quadriceps  of 
the  thigh  is  homologous  with  the  triceps 
extensor  of  the  arm,  the  fourth  head  of 
the  latter  muscle  being  the  anconeus. 
The  sartorius  normally  has  no  homo- 
logue  in  the  upper  extremity,  but  is 
sometimes  represented  by  a  slip  from 
the  latissimus  dorsi  to  the  triceps  (dorsi- 
epitrochlearis — Macalister).  The  rectus 
arises  by  an  anterior  or  straight  head 
from  the  anterior  inferior  spine  of  the 
ilium  and  a  posterior  or  reflected  head 
from  the  upper  surface  of  the  rim  of 
the  acetabulum.  The  tendon  formed  by 
the  union  of  these  two  heads  passes 
downward  directly  over  the  head  of  the 
femur  and,  in  operating  on  the  joint 
from  in  front,  it  must  be  deflected  to 
one  side.  The  belly  of  the  muscle  is 
separate  and  not  attached  to  the  other 
muscles  (Fig.  529), 

The  vastus  externus  (vastus  late- 
ralis) forms  the  muscular  mass  on  the 
outer  surface  of  the  thigh.  A  bursa 
separates  it  from  the  gluteus  maximus 
above.  Superficially  it  is  readily  sepa- 
rated from  the  crureus  (vastus  inter- 
medius)  but  blends  with  it  close  to  the 
bone.  The  line  separating  the  two  mus- 
cles is  directly  upward  from  the  outer 
edge  of  the  patella.  The  vastus  internus 
(vastus  medialis)  arises  from  the  inner 
edge  of  the  linea  aspera  as  high  up  as 
the  lesser  trochanter.  Its  outer  ^<\^q. 
blends  with  the  crureus. 

The  sartorius  in  the  middle  third 
of  the  thigh  lies  directly  over  Hunter's 
canal.  It  inserts  into  the  tibia  below  and 
internal  to  its  tubercle,  hence  it  spans 
both  the  hip-joint  and  knee-joint.  It 
flexes  the  thigh  on  the  pelvis  and  the  leg 
on  the  thigh.  It  also  rotates  the  thigh 
outward  and  the  leg  inward  especially 
when  the  latter  is  flexed. 

The  flexor  muscles,  also  called 

Fig.  529.— The  quadriceps  extensor  muscle  of  the  thigh,      the  hamstring  mUSCleS,  comprise  the 

biceps  cruris,  \.\\e  semite7idinosics,  and  the 
semimembrayiosus.  The  short  head  of  the  biceps  arises  from  the  outer  lip  of  the  linea 
aspera.  Above,  the  long  head  is  blended  with  the  semitendinosus  and  arises  from  the 
great  sacrosciatic  ligament  and  the  lower  inner  part  of  the  tuberosity  of  the  ischium. 


Rectus  fetnoris 

with  crureus 

beneath 


Vastus 
externus 


Vastus 
internus 


THE   THIGH. 


521 


The  semimembranosus  arises  from  the  tuberosity  just  above  and  external  to  the  biceps 
and  semitendinosus.  The  biceps,  arising  by  its  long  head  from  the  tuberosity,  lies  first 
to  the  inner  side  of  the  sciatic  nerve,  and  then,  as  it  crosses  obliquely  to  reach  the 


Adductor 
magnus 


Adductor 
tubercle 


Fig.  530. — The  flexor  muscles  of  the  thigh. 


Fig.  S3'. — Adductor  muscles  of  the  thigh. 


outer  side  of  the  knee,  covers  the  nerve  and  finally  lies  to  its  outer  side.  The  upper 
portion  of  the  semimembranosus  lies  beneath  both  the  long  head  of  the  biceps  and 
the  semitendinosus,  and  only  comes  to  the  surface  between  them  from  the  middle  of 


522  "^^^  APPLIED    ANATOMY.  "^^M^^^^ 

the  thigh  down.  The  tendons  of  the  semimembranosus  and  semitendinosus  form 
the  inner  hamstring  tendons  and  the  biceps  the  outer  hamstring  tendon  (Fig.  530). 

The  adductor  muscles  are  the  adductor  brevis,  adductor  longus^  adductor 
7nag7ms,  and  gracilis ;  for  cHnical  purposes  the  pectineus  may  also  be  inckided, 
although  it  is  morphologically  simply  a  detached  portion  of  the  iliacus.  The  quad- 
ratics femoris  and  obturator  externus  belong  morphologically  to  the  adductor  group, 
but  from  a  clinical  standpoint  they  are  associated  more  with  the  external  rotators  of 
the  hip  than  the  adductors  of  the  thigh.  The  adductor  muscles  separate  the  flexor 
and  extensor  groups  on  the  inner  side  of  the  thigh.  The  adductor  longus  arises 
by  a  strong  tendon  from  the  body  of  the  pubis  just  below  its  spine  and  inserts  into 
approximately  the  middle  third  of  the  femur  in  the  linea  aspera  (Fig.  531).  When 
the  thigh  is  abducted  the  tense  edge  of  its  tendon  is  evident,  and  if  followed  upwards 
it  leads  to  the  spine  of  the  pubis.  It  lies  on  the  same  plane  as  the  pectineus,  which  is 
immediately  above;  sometimes,  especially  in  the  female,  an  interval  exists  between  the 
two  through  which  the  adductor  brevis  may  be  visible.  Near  its  insertion  it  forms 
part  of  the  floor  of  Scarpa' s  triangle  and  the  upper  part  of  the  floor  of  Hunter's  canal. 

The  adductor  brevis  arises  from  the  descending  ramus  of  the  pubis  just  below 
the  origin  of  the  adductor  longus  and  inserts  into  the  femur  from  the  lesser  trochanter 
to  the  linea  aspera.  It  lies  directly  behind  the  upper  portion  of  the  adductor  longus 
and  in  front  of  the  adductor  magnus. 

The  adductor  magnus  arises  from  the  ramus  of  the  ischium,  from  the  adductor 
brevis  in  front  to  the  hamstring  tendons  on  the  tuberosity  behind.  It  is  inserted  into 
nearly  the  whole  length  of  the  linea  aspera,  and  by  a  distinct  tendinous  band  into 
the  adductor  tubercle  at  the  upper  edge  of  the  internal  condyle.  Its  upper  portion 
is  sometimes  called  the  adductor  minimus.  It  is  pierced  near  the  bone  by  the  per- 
forating branches  of  the  profunda  femoris  artery  and  near  its  lower  portion  by  the 
femoral  artery  and  vein.  It  forms  part  of  the  floor  of  Hunter's  canal.  Its  homologue 
in  the  upper  extremity  is  the  coracobrachialis  muscle. 

The  gracilis  arises  from  the  pubis  just  to  the  inner  side  of  the  adductor  brevis  and 
passes  straight  down  the  thigh  to  insert  into  the  tibia,  beneath  the  sartorius  and  above 
the  semitendinosus.  It  is  sometimes  represented  in  the  upper  extremity  by  a  slip 
from  the  lower  border  of  the  pectoralis  major  called  the  chondro-epitrochlearis. 

The  pectineus  arises  from  the  iliopectineal  line  to  insert  just  behind  and  below  the 
lesser  trochanter.     It  lies  on  the  same  level  as  the  adductor  longus  and  just  above  it. 

SURFACE   ANATOMY. 

If  the  thigh  is  flexed  and  rotated  outward  the  sartorius  is  seen  crossing  it  obliquely, 
and  Scarpa's  triangle  is  evident  as  a  depression  downward  from  Poupart's  ligament. 
The  muscular  mass  of  the  upper  inner  portion  of  the  thigh  is  composed  of  the 
gracilis  and  adductor  muscles.  Immediately  above  the  patella  is  the  flat  tendon  of 
the  rectus,  and  above  and  to  the  inner  side  of  the  patella  is  a  rounded  mass  formed 
by  the  vastus  internus  (Fig.  532).  Running  upward  and  inward  from  the  outer 
edge  of  the  patella  to  the  middle  of  the  thigh  is  a  groove  which  separates  the  rectus 
and  vastus  externus.  On  the  outer  side  a  flat  groove  is  formed  by  the  iliotibial 
band  of  the  fascia  lata.  At  its  posterior  border  is  the  external  intermuscular  septum 
between  the  vastus  externus  and  biceps. 

Scarpa's  Triangle.  —  This  occupies  approximately  the  upper  third  of  the 
thigh.  Its  base  is  formed  by  Poupart's  ligament,  its  outer  side  by  the  sartorius 
muscle,  and  its  inner  side  by  the  adductor  longus.  Its  floor  is  formed  by  the  iliacus, 
psoas,  pectineus,  sometimes  a  portion  of  the  adductor  brevis,  and  the  adductor  longus 
muscles.  It  contains  the  femoral  artery  and  vein,  the  anterior  crural  nerve,  the  long 
saphenous  vein,  and  numerous  lymphatics  (Fig.  533).  At  its  upper  and  inner  part  is 
the  saphenous  opening,  at  which  femoral  herniae  make  their  appearance.  Psoas 
abscesses  follow  the  tendon  of  the  psoas  muscle  down  and  make  their  appearance  in 
Scarpa's  triangle,  sometimes  to  one  side  and  sometimes  to  the  other  of  the  artery. 
Pus  from  hip-joint  disease  likewise  comes  to  the  front  at  the  upper  part  of  the  triangle 
on  one  side  or  the  other  of  the  femoral  artery.  The  apex  of  Scarpa's  triangle  is  a 
favorite  site  for  ligation  of  the  femoral  artery. 


THE   THIGH. 


523 


Femoral  Artery. — The  line  of  the  femoral  artery  is  from  a  point  midway 
between  the  anterior  superior  spine  and  the  symphysis  pubis  (this  brings  it  to  the 
inner  side  of  the  middle  of  Poupart's  ligament)  to  the  adductor  tubercle  at  the  inner 
upper  part  of  the  internal  condyle.  Just  below  Poupart's  ligament  it  gives  off  four 
small  branches;  the  superficial  external  circumflex,  superficial  epigastric,  and  superfi- 
cial and  deep  external  pudic.  About  4  cm.  ( i yi  in.  )  down  it  gi\es  of?  the  profunda 
femoris,  which  is  almost  as  large  as  the  parent  trunk.  On  reaching  the  edge  of  the 
sartorius  it  passes  beneath  it  to  enter  Hunter's  canal,  and  at  the  junction  of  the  mid- 
dle and  lower  third  of  the  thigh  it  pierces  the  adductor  magnus  to  become  the 
popliteal.  At  Poupart's  ligament  the  femoral  vein  lies  to  the  inner  side  of  the 
artery,  but  at  the  apex  of  the  triangle  it  lies  behind  it. 

Ligation  of  the  Femoral  Artery. — In  ligating  the  femoral  artery  an  incision  is 
made  in  the  line  given  above,  and  the  artery  sought  for  beneath  the  fascia  lata.  Lig- 
atures are  not  placed  high  up,  on  account  of  the  proximity  of  the  deep  femoral; 
lower  down  at  the  apex  of  the  triangle  is  the  preferred  point.  The  crural  branch  of 
the  genitocrural  nerve  lies  on  the  artery  for  a  short  distance  below  Poupart's  ligament; 
it  is  small  in  size.     Just  to  the  outer  side  of  the  artery,  and  sometimes  touching  it,  is 


Rectus  femoris 
Vastus  internus 

Adductor  tubercle 

Line  of  femoral 
artery 

Gracilis  and  adduc- 
tor muscles 

Sartorius 
Scarpa's  triangle 


Saphenous  opening 


Fig.  532. — Surface  anatomy  of  the  thigh. 


the  anterior  crural  nerve,  and  running  down  its  outer  side  are  the  internal  cutaneous 
and  internal  saphenous  branches.  The  femoral  vein,  which  above  was  internal  to 
the  artery,  at  the  apex  of  the  triangle  lies  posterior  to  it  (Fig.  534). 

The  profunda  femoris  artery  conies  off  4  cm.  (i^  in.)  below  Poupart's  liga- 
ment. Its  branches  are  the  external  (lateral)  and  internal  (medial)  circumflex,  and 
four  perforating.  The  last  perforating  is  terminal.  The  external  circunijiex  passes 
outward  over  the  iliacus  and  under  the  sartorius  and  rectus  and  divides  into  three 
branches;  the  ascending  branch  follows  the  anterior  intertrochanteric  line  and  gives 
off  a  branch  which  enters  the  joint  between  the  limbs  of  the  iliofemoral  or  Y  liga- 
ment. The  transverse  branch  goes  outward  to  the  upper  part  of  the  vastus  exter- 
nus;  and  the  descending  branch  supplies  the  muscle  lower  down.  The  ascending 
and  transverse  branches  lie  beneath  the  incision,  which  is  made  in  operating  on  the 
hip-joint  anteriorly,  and  may  be  cut  during  the  operation.  The  interjial  circumflex 
winds  inwardly  between  the  psoas  and  pectineus,  then  between  the  adductor  brevis 
and  obturator  externus,  and  then  between  the  adductor  magnus  and  quadratus  fem- 
oris to  anastomose  with  the  external  circumflex,  sciatic,  and  superior  perforating. 

The  {o\xx  perforating  arteries  wind  around  close  to  the  bone  from  within  outward 
and  terminate  in  the  hamstring  and  vastus  externus  muscles.  They  perforate  the 
adductor  muscles  and  send  large  anastomotic  branches  to  one  another  near  the  linea 
aspera.  In  operations  on  the  femur,  when  the  soft  parts  are  detached  from  the 
posterior  portion  of  the  bone,  the  bleeding  from  these  perforating  branches  is  liable 
to  be  v^ery  free  and  on  account  of  their  depth  difficult  to  control.  It  is  this  which 
renders  operations  like  those  for  ununited  and  compound  fractures  dangerous. 


524 


APPLIED    ANATOMY. 


Hunter's  Canal. — Hunter's  canal  occupies  approximately  the  middle  third 
of  the  thigh.  It  has  an  outer  wall  formed  by  the  vastus  internus  muscle;  a  floor 
formed  above  by  the  adductor  longus,  and   below  by  the  adductor  magnus;  and  a 


Superficial  epigastric 

Superficial  external  pudic 
Deep  external  pudic 

Pectineus 
Adductor  brevis 

Adductor  longus 
Long  saphenous  vein 

Nerve  to  vastus  internus 

Femoral  vein 

Femoral  artery 

Long  saphenous  nerve 

Hunter's  canal  (roof) 

Adductor  magnus 

Sartorius 


Vastus  internus 


Superficial  circumflex  iliac 
External  cutaneous  nerve 

Iliacus 
Sartorius 

Tensor  fascias  femoris 
Anterior  crural  nerve 
Femoral  artery 

Femoral  vein 

Middle  cutaneous  nerve 


Iliotibial  band  of  fascia  lata 
Rectus  femoris 
Vastus  externus 


Fig.  533. — Anterior  view  of  the  structures  of  the  thigh,  Scarpa's  triangle  and  Hunter's  canal. 

roof  formed  by  a  layer  of  fascia  running  from  the  adductor  longus  and  magnus  below 
to  the  vastus  internus  on  the  outer  side.  The  canal  runs  from  the  apex  of  Scarpa's 
triangle  to  the  opening  in  the  adductor  magnus  muscle.  The  sartorius  muscle  lies 
on  the  roof  of  the  canal  (Fig.  533). 


THE   THIGH. 


525 


The  Femoral  Artery  in  Hmiter  s  Canal. — The  femoral  artery  in  Hunter's  canal 
has  the  vein,  to  which  it  is  closely  bound  by  fibrous  tissue,  first  posterior  and  then 
slightly  to  its  outer  side.  The  internal  or  long  saphenous  nerve  crosses  the  artery  in 
front  from  its  outer  to  its  inner  side.  At  the  beginning  of  the  canal  the  nerve  to 
the  vastus  internus  runs  alongside  of  the  long  saphenous  nerve,  but  it  soon  leaves  it 
to  enter  the  muscle.  The  long  saphenous  nerve  lea\'es  the  artery  as  the  latter  per- 
forates the  adductor  magnus  and  passes  downward  under  the  sartorius  muscle  to 
be  distributed  to  the  leg  lower  down,  and  to  the  inner  side  of  the  ankle. 

Ligation  of  the  Femoral  Artery  i7i  Hjinters  Canal. — In  ligating  the  artery 
the  incision  is  made  over  the  sartorius  muscle,  which  is  to  be  pulled  to  the  outer 
side;  this  exposes  the  roof  of  the  canal,  which  is  then  opened.     There  is  no  need  of 


Skin 

Superficial  fascia 

Fascia  lata 

Sartorius  muscle 


Skin 

Superficial  fascia 

Fascia  lata 

Femoral  vein 
Femoral  artery 

Long  saphenous  nerve 


External  condyle  of  femur - 


.Patella 


Fir..   534. — Ligation  of  the  femoral  artery  at  the  apex  of  Scarpa's  triangle. 

including  the  long  saphenous  nerve  in  the  ligature.  Just  before  the  femoral  artery 
pierces  the  adductor  magnus  it  gives  off  the  anastomotica  magna,  whose  superficial 
branch  follows  the  long  saphenous  nerve,  while  its  deep  branch  supplies  the  vastus 
internus  muscle.  This  latter  branch  may  be  the  source  of  troublesome  hemorrhage 
in  supracondylar  osteotomy. 

Collateral  Circnlation. — After  ligation  of  the  femoral  artery  below  its  profunda 
branch  the  external  circumflex  artery  anastomoses  with  the  muscular  branches  of  the 
femoral,  anastomotica  magna,  and  superior  articular  arteries.  The  perforating  arte- 
ries anastomose  with  the  muscular  branches  below  the  ligature  and  with  the  superior 
articular  arteries  (Fig.  535). 

Long  or  Internal  Saphenous  Vein. — The  long  saphenous  vein  begins  in 
the  venous  arch  on  the  dorsum  of  the  foot  and  passes  upward  just  in  front  of  the 
internal  malleolus,  then  along  the  inner  posterior  edge  of  the  tibia,  accompanied  by 


526 


APPLIED    ANATOMY. 


the  long  saphenous  nerve,  then  along  the  posterior  border  of  the  internal  condyle 
and  up  in  almost  a  straight  line  to  the  saphenous  opening,  4  cm.  ( i  ^  in. )  below  and 
to  the  outer  side  of  the  spine  of  the  pubis,  where  it  empties  into  the  femoral 
vein.  It  is  this  vein  which  is  involved  in  varicose  veins  of  the  leg,  and  is  frequently 
operated  on.  The  blood  from  the  inner  and  outer  portions  of  the  thigh  collects  into 
two  veins  which  empty  into  the  long  saphenous  before  the  saphenous  opening  is 


External  circumflex 


Profunda  femoris 


Femoral  artery 


Perforating  arteries  from  profunda^ 


Superior  external  articular 


Azygos  articular 


Inferior  external  articular 


Internal  circumflex 


-^Anastomotica  magna 


Superior  internal  articular 


Inferior  internal  articular 


Fig.   53 S. — Collateral  circulation  after  ligation  of  femoral  artery. 

reached,  or  else  join  the  vein  at  the  saphenous  opening,  or  else  open  separately 
into  the  >  femoral  vein.  There  are  then  sometimes  two  or  three  veins  at  the 
saphenous  opening  coming  from  below,  instead  of  one.  This  is  important  to  bear  in 
mind  when  operating  here,  otherwise  one  of  the  side  veins  may  be  ligated  or  excised 
under  the  impression  that  it  is  the  main  trunk.  Every  opportunity  should  be  utilized 
to  impress  on  one's  mind  the  exact  course  pursued  by  the  vein,  as  otherwise  it  may 
not  be  readily  found  if  not  rendered  conspicuous  by  distention  or  disease. 


THE   THIGH. 


527 


Lymphatics  of  the  Groin. — The  lymphatic  nodes  of  the  groin  are  frequently 
the  seat  of  infection  necessitating  operative  measures.  They  are  superficial  and  deep. 
For  clinical  purposes  there  is  no  better  division  of  the  superficial  nodes  than  into  an 
oblique  set  along  Poupart's  ligament  and  a  longitudinal  set  along  the  blood-vessels 
(Fig.  536). 

While  as  a  general  rule  it  may  be  stated  that  the  nodes  drain  the  region  they 
are  nearest  to,  this  is  frequently  not  the  case.     Therefore  it  is  not  always  possible  to 
infer  the  source  of  the  infection  from  the  location  of  the  infected  lymph  node.      The 
nodes  of  the  groin  drain  the  lower  anterior  half  of  the 
abdomen,  the  genitalia,  lower  limb,  and  the  anal,  gluteal, 
and  lumbar  regions. 

They  vary  from  10  to  20  in  number,  and  their 
efferent  vessels  either  pass  through  the  femoral  canal  to 
the  nodes  inside  of  the  abdomen,  or  may  terminate  in 
the  deep  lymphatic  nodes  of  the  femoral  canal. 

The  deep  lymphatics  consist  of  one  to  three  nodes 
in  the  femoral  canal  internal  to  the  femoral  vessels. 
They  are  not  constant,  and  one  which  is  sometimes 
found  at  the  upper  end  of  the  femoral  canal  is  known 
as  the  gland  or  node  of  Cloquet.  They  receive  the  deep 
lymphatics  of  the  thigh,  as  well  as  sometimes  a  commu- 
nication from  the  superficial  lymphatics.  They  rarely 
become  the  seat  of  infection,  but  if  inflamed  may  be 
mistaken  for  strangulated  femoral  hernia. 

Excision  of  Inguinal  Nodes. — The  inguinal 
nodes  frequently  become  inflamed  and  swollen  (bubo) 
•from  infection  transmitted  from  the  parts  which  they 
drain.  For  this  they  are  frequently  excised.  The 
superficial  nodes  are  located  on  the  fascia  lata  around 
the  saphenous  opening,  and  at  that  point  are  intimately 
associated  with  and  surround  the  veins.  On  this  ac- 
count it  is  easy  to  wound  the  veins,  and  the  hemor- 
rhage may  be  so  free  and  so  hard  to  control  as  to  en- 
danger the  life  of  the  patient.  I  know  of  one  such 
fatal  case.  This  accident  is  to  be  avoided  by  freeing 
the  edge  of  the  mass  below  the  saphenous  opening 
and  isolating  the  long  saphenous  vein,  which  is  then 
followed  up  and  exposed  at  its  entrance  into  the  femoral 
vein.  The  diseased  mass  is  then  to  be  dissected  loose 
from  each  side,  away  from  the  vein,  and  removed.  The 
femoral  vein  itself  at  this  point  is  superficial,  and  if  the 
saphenous  opening  is  cleaned  out  it  will  of  necessity 
be  exposed. 

The  other  veins  emptying  into  the  femoral  at  the 
saphenous  opening  above  the  long  saphenous — the  su- 
perficial circumflex  iliac,  epigastric,  and  external  pudic — 
are  usually  too  small  and  easily  secured  to  cause  trouble. 

Sciatic  Nerve. — The  sciatic  nerve  in  its  descent 
crosses  a  line  joining  the  tuberosity  of  the  ischium  and 
greater  trochanter  at  the  junction  of  its  inner  and  middle  thirds.  It  then  descends 
toward  the  middle  of  the  popliteal  space.  It  divides  into  the  internal  and  external 
popliteal  nerves  at  about  the  middle  of  the  thigh  (Fig.  537).  Rarely  it  divides 
lower  down,  but  more  frequently  higher  up.  It  is  said  that  it  will  bear  a  weight 
of  183  lbs.,  but  Symington  {Lancet,  1878 — Treves)  has  pointed  out  that  it  will  tear 
out  from  its  spinal  attachment  before  this  limit  is  reached.  In  exposing  it  the  incision 
should  be  made  high  up  at  the  gluteal  fold,  to  the  outer  side  of  the  tuberosity  of  the 
ischium.  At  this  point  it  lies  to  the  outer  side  of  the  biceps  and  on  the  adductor 
magnus;  a  little  lower  down  it  disappears  beneath  the  biceps,  and,  if  the  incision 
is  made  here,  the  muscle  must  be  displaced  and  it  may  only  be  found  with  difficulty. 


Fig.  536. — Superficial  lymphatic 
vessels  of  lower  limb;  semicliagram- 
matic.    (Based  on  figures  of  Sappey.) 


528 


A-PPLIED    ANATOMY. 


At  the  upper  end  of  the  popHteal  space  it  again  becomes  visible,  and  can  be  fount 
between  the  biceps  on  the  outer  side  and  the  semimembranosus  on  the  inner  side. 


Gluteus  minimus 


Gluteus  medius 


Obturator  internus 


Gluteus  maximus 


Short  head  of  biceps 


External  popliteal  or 
fibular  nerve 

Plantaris 


Outer  head  of  gastrocnemius 


Pyriformis 
Sciatic  artery 
Small  sciatic  nerve 
Sciatic  nerve 
Gemelli 

Comes  nervi  ischiadic! 
Long  head  of  biceps 


Semimembranosus 


Semitcndinosis 


Gracilis 

Semimembranosus 

Sartorius 

Semitendinosus 

Internal  popliteal  or  tibial  jierve 

Popliteal  artery 


Fig.   537. — Sciatic  nerve  and  structures  of  the  posterior  portion  of  the  thigh. 

Sciatica  may  be  caused  by  injury  to  the  sacral  plexus  in  the  pelvis,  as  by  labor, 
or  by  injury  to  the  nerves  as  they  issue  from  the  spine,  as  in  fractures,  luxations,  bony 
outgrowths  or  tumors.    The  pain  aflects  the  back  of  the  thigh  and  outer  side  of  the  leg. 


THE   THIGH. 


529 


FRACTURES   OF   THE   FEMUR. 

The  femur  is  usually  fractured  through  the  neck,  greater  trochanter,  upper 
third  of  the  shaft,  middle  of  the  shaft,  or  just  abo\e  the  condyles. 

Fractures  of  the  Neck  of  the  Femur. — These  are  often  difficult  of  diagnosis 
and  unsatisfactory  in  treatment. 

The  signs  peculiar  to  this  fracture  are  due  to  the  displacement  of  the  fragments. 
Some  shortening  occurs  in  all  fractures  of  the  femur  (Fig.  538).  Comparative 
measurements  to  ascertain  this  will  be  of  no  value  if  the  pelvis  is  tilted  (see  page 
497).  If  by  measurement  the  limb  is  shorter  than  the  opposite  one,  then  if  the  dis- 
tance from  the  tip  of  the  greater  trochanter  to  the  external  malleolus  is  the  same  on 
both  sides,  the  injury  must  be  higher  up,  or  in  the  neck. 

The  iliotrochanteric  angle  instead  of  being  thirty  degrees  will  be  diminished  or 
lost.     The  tip  of  the  greater  trochanter  will  be  above  the  Roser-Nelaton  line.     The 


Fig.  538. — Intracapsular  fracture  of  the  neck  of 
the  femur  showing  the  shortening.  The  dotted  line 
represents  the  outline  of  the  normal  bone. 


Fig.  539. — View  of  the  outer  surface  of  the 
bones  of  the  hip,  showing  Roser-Nelaton  line 
(ad);  Bryant's  triangle  (a  be  —  be  being  its 
base) ;  the  iliotrochanteric  line  (a  c)  and  iliotro- 
chanteric angle  {bac). 


base  of  Bryant's  triangle  will  be  shorter  on  the  injured  side  (Fig.  539).  If  the  ex- 
tended limb  is  rotated  the  arc  described  by  the  greater  trochanter  will  be  smaller 
on  the  injured  side  because  the  shaft  rotates  on  its  axis  instead  of  rotating  in  the 
acetabulum.  The  trochanter  of  the  injured  side  is  usually  not  so  prominent  as  on 
the  sound  side.      The  iliotibial  band  is  relaxed. 

Shortening  is  well  demonstrated  by  flexing  the  thighs  with  the  patient  on  his  back: 
the  knee  of  the  sound  side  will  be  found  to  be  higher  than  that  of  the  injured  one. 

In  all  fractures  of  the  thigh  the  foot  is  placed  by  gravity  in  eversion.  The  rise 
of  the  greater  trochanter,  being  nearer  to  the  crest  of  the  ilium,  produces  a  slight 
fulness  in  the  outer  portion  of  Scarpa's  triangle  which  is  absent  on  the  healthy  side. 

Luie  of  Fracture. — The  neck  is  fractured  in  one  of  two  places,  near  the  head, 
or  near  the  trochanter.  The  former  is  intracapsular  entirely,  the  latter  partly  intra- 
capsular and  partly  extracapsular.  As  the  capsule  anteriorly  descends  as  low  as  the 
34 


530 


APPLIED   ANATOMY. 


intertrochanteric  line  and  posteriorly  only  half  way  down  the  neck,  the  high  frac- 
tures are  entirely  intracapsular  and  the  low  fractures  intracapsular  in  front  and 
extracapsular  behind.  This  causes  a  marked  difference  in  healing;  complete  intra- 
capsular fractures  do  not  unite  firmly,  but  the  fractures  close  to  the  trochanters 
not  infrequently  unite  firmly  with  resulting  good  function. 


Tensor  fasci;e  femoris 

Gluteus  medius 

Gluteus  minimus 


Rectus  femoris 


Crureus 


Vastus  intemus 


Iliopsoas 

Pectineus 
Adductor  brevjs 

Adductor longus 


Gracilis 


Adductor  magnus 


\ 

Fig.  S40. — Fracture  of  the  femur  at  the  juncture  of  the  upper  and  middle  thirds.    Upper  fragment  drawn  forward 

and  outward. 


i 


Impactio7i. — Impaction  of  the  other  fragment  by  the  neck  of  the  bone  is  not 
rare,  and  firm  union  may  occur.  If  the  fracture  is  close  to  the  head,  the  neck  is 
impacted  into  and  penetrates  the  head,  but  if  the  fracture  is  close  to  the  trochanters 
the  neck  penetrates  the  trochanters,  frequently  splitting  them. 


THE   THIGH. 


531 


Plantaris 

Two  heads 
of  the 
gastrocnemius 


Mode  of  Injury. — In  old  people  the  bone  is  weakened  by  atrophy  and  the  neck 
is  often  fractured  by  indirect  violence,  as  by  twisting,  etc.  Then  the  fracture  is  a 
high  one;  if,  however,  the  fracture  is  by  direct  violence,  as  by  falling  and  striking 
the  hip,  then  the  fracture  is  apt  to  be  close  to  the  trochanters  and  the  prognosis 
better.  Hence  the  importance  of  ascertaining  the  history  of  the  injury.  Fracture 
also  occurs  in  young  adults  and  children,  usually  from  direct  injury. 

Treatment.  — The  injury  is  treated  ( i )  by  widely  abducting  the  thigh,  which  ele- 
vates the  lower  fragment  to  the  upper;  (2)  by  adhesive  plaster  extension  combined 
with  lateral  weight  traction  pulling  the  upper  part  of  the  thigh  out,  which  renders  tense 
the  capsule  and  so  brings  the  fractured  surfaces  in  apposition;  or  (3)  by  Thomas's 
splint  which  is  of  metal  and  extends  from  the  level  of  the  axilla  to  below  the  knee; 
this  ensures  immobility  and  facilitates 
handling  of  the  patient. 

Fracture  through  the  Tro- 
chanters.—  This  is  almost  always 
the  result  of  a  direct  injury  or  blow 
on  the  hip.  Impaction  is  almost  the 
rule,  the  upper  fragment  being  driven 
into  the  lower.  Shortening  and  other 
symptoms  are  usually  not  so  marked 
as  in  the  other  fractures  and  almost 
any  method  of  treatment  is  followed 
by  good  results. 

Fractures  of  the  Shaft. — 
These  may  be  in  the  upper,  middle,  or 
lower  third.  They  all  have  a  common 
displacement.  The  upper  fragment  is 
displaced  forward  and  outward  and 
the  lower  fragment  backward  and 
usually  inward.  The  foot  is  usually 
everted. 

Fractures  of  the  Upper  Third. — 
The  displacement  of  the  upper  frag- 
ment forward  and  outward  is  usually 
marked.  It  is  caused  by  the  iliacus, 
psoas,  and  pectineus  pulling  it  for- 
ward and  rotating  it  out  and  the 
gluteus  minimus  and  medius  abduct- 
ing it.  The  lower  fragment  is  pulled 
in  by  the  adductors  and  posteriorly 
by  the  gastrocnemius  and  plantaris 
(Fig.  540).  This  is  a  troublesome 
fracture  and  is  treated  either  by  a 
double  inclined  plane  or  anterior 
wire  splint  with  the  limb  in  a  flexed 
and  abducted  position  or  else  the  fragments  are  to  be  wired  or  pinned  together. 

Fracture  of  the  Middle  Third. — The  displacement  is  the  same  as  in  the  upper 
third  but  to  a  less  extent.  It  is  usually  treated  by  adhesive  plaster  extension  with 
the  leg  abducted. 

Fractures  of  the  Lower  Third — Supracondylar. — This  is  a  particularly  danger- 
ous fracture  because  the  lower  fragment  is  drawn  backward  by  the  gastrocnemius  and 
plantaris,  and  the  popliteal  vessels  and  internal  popliteal  nerve  may  either  be  wounded 
primarily  or  stretched  over  its  sharp  upper  edge  (Fig.  541).  The  artery  lying  deepest 
is  the  most  liable  to  injury,  then  the  vein,  and  finally  the  nerve.  Gangrene  necessi- 
tating amputation  has  occurred.  Of  course  in  attempting  to  replace  the  fragments 
the  knee  should  be  flexed  to  relax  the  gastrocnemius  and  plantaris.  Some  cases  can 
be  treated  by  ordinary  extension  with  the  knee  straight,  others  with  the  knee  flexed, 
but  others  may  require  operation  and  fixing  by  pins  or  wiring.  William  Bryant 
divided  the  tendo  Achillis  for  the  purpose  of  relaxing  the  pull  of  the  gastrocnemius. 


Fig.  541.  —  Supracondylar  fracture  of  the  femur.  The 
lower  fragment  is  seen  to  be  drawn  back  into  the  popliteal 
space  by  the  gastrocnemius  and  plantaris.  The  vessels  are 
stretched  over  the  sharp  edge  of  the  lower  fragment. 


532  APPLIED   ANATOMY. 

AMPUTATION. 

Amputation  at  the  Hip-Joint.  —  In  amputating  at  the  hip-joint,  hemor- 
rhage is  especially  to  be  guarded  against.  This  comes  from  two  sources,  the  femoral 
artery  anteriorly  and  the  branches  of  the  internal  iliac  posteriorly.  The  most  reliable 
way  of  controlling  bleeding  is  probably  by  the  use  of  the  elastic  tourniquet  held  in 
place  by  Wyeth's pins.  These  are  two  steel  pins  5  mm.  (f'g  in.)  in  diameter  and 
25  cm.  (loin.  )long.  One  is  entered  6  mm,  {}^  in.)  below  the  anterior  superior 
spine  and  slightly  to  its  inner  side  and  traverses  the  tissues  on  the  outer  side  of 
the  hip  for  about  7.5  cm.  (3  in.)  from  the  point  of  entrance;  the  other  is  entered 
through  the  skin  and  tendon  of  the  adductor  magnus  1.25  cm.  (^  in.)  below  the 
perineum  and  made  to  emerge  2.5  cm.  (i  in.)  below  the  tuber  ischii.  The  elastic 
tube  is  to  be  wound  around  the  hip  above  the  pins,  which  prevent  its  slipping  down 
(Fig.  542).  The  amputation  is  then  performed  as  desired.  Compression  of  the 
aorta  or  common  iliac  by  instrumental  means  is  obsolete.  Sometinies  the  common 
iliac  is  compressed  laterally  by  the  linger  introduced  through  an  incision  in  the 


Sartorius --^ J^^^  //^OS<,      ^^  ^^-Femoral  artery 

Anterior  crural  nerve  ~-~._;__^^\-^  V^H^^iii,,^       '''  -- Femoral  vein 


Vastus  internus 


Rectus  and  crureus  - 


Vastus  externus' 


Adductors 


.  Gracilis 


^^^H^^^I^H^^^  ^~\  Semimembranosus  and 

^^.^^•^^^^^W^P'^^N.  semitendinosus 

Biceps  Sciatic  nerve 

Fig.  S42- — ^Amputation  just  above  the  middle  of  the  thigh,  showing  insertion  of  Wyeth's  pins. 

abdominal  walls.  Another  method  consists  in  making  lateral  flaps  with  the  femoral 
artery  in  the  angle  of  the  incision — all  vessels  are  then  clamped  as  they  are  divided. 

In  some  operations  the  head  of  the  femur  is  disarticulated  before  the  flaps  are 
made.  In  this  case  the  first  part  of  the  operation  is  like  a  resection  of  the  hip 
by  the  Langenbeck  straight  incision. 

The  bleeding  of  the  posterior  flap  comes  from  branches  of  the  gluteal,  sciatic, 
obturator,  and  internal  pudic  arteries,  derived  from  the  internal  iliac. 

Amputation  of  the  Thigh. — In  amputation  of  the  thigh  by  the  flap  method 
care  must  be  taken  to  avoid  splitting  the  femoral  artery.  Its  position  in  the  various 
portions  of  the  thigh  should  be  borne  in  mind.  Anteroposterior  flaps  are  to  be  pre- 
ferred to  lateral  ones,  and  a  short  anterior  flap  is  to  be  avoided  because  the  scar  is 
drawn  posteriorly  (Fig.  542).  The  muscles  of  the  posterior  part  of  the  thigh,  the 
hamstrings,  are  not  attached  to  the  bone,  with  the  exception  of  the  short  head  of 
the  biceps,  they  therefore  retract  when  cut  and  later  pull  the  scar  behind  the  bone. 
The  crureus  and  vastus  externus  and  internus  anteriorly  are  attached  to  the  bone, 
and  hence  cannot  draw  back  either  at  the   time  of  the  operation  or  afterwards. 


REGION    OF   THE    KNEE. 


533 


The  position  of  the  femoral  artery  will  depend  on  the  point  at  which  the  amputation 
is  made.  It  does  not  lie  close  to  the  bone  until  the  popliteal  space  is  reached. 
Bleeding  from  the  perforating  arteries  along  the  linea  aspera  should,  however,  be 
looked  for  and  the  sciatic  nerve  should  be  isolated  and  cut  short. 


REGION   OF  THE   KNEE. 


External  con-_ 
dyle  of  femur' 


SURFACE   ANATOMY. 

The  bony  landmarks  are  the  patella,  the  two  condyles  of  the  femur,  the  tibia, 
and  the  fibula  (Fig.  543). 

The  patella  is  pointed  below  where  the  tendo  patellae  is  attached,   is  slightly 
convex  on  its  upper  border,   and  its  lateral  edges  are  prominent,   especially   the 
outer.     It   usually  has  little  tissue 
over  it.   With  the  limb  extended  and  , 

quadriceps  relaxed  the  patella  can 
be  moved  laterally.  There  is  a  hol- 
low above  the  patella.  When  the 
muscle  contracts  this  hollow  is  filled 
up  by  the  rectus,  and  the  muscular 
swells  on  each  side  produced  by  the 
vastus  internus  and  externus  are 
visible.  When  the  quadriceps  mus- 
cle is  contracted  the  tense  tendo 
patellae  becomes  evident,  when  re- 
laxed the  soft  fatty  pad  beneath  the 
tendon  can  be  felt. 

About  midway  between  the 
patella  and  tubercle  of  the  tibia  on 
each  side  can  be  felt  a  groove  which 
indicates  the  line  of  the  joint  and 
the  location  of  the  semilunar  carti- 
lages. On  the  outer  side  posteriorly 
opposite  the  level  of  the  tibial  tuber- 
cle can  be  felt  the  head  of  the  fibula. 
Running  upward  from  it  is  the  ten- 
don of  the  biceps.  In  front  of  the 
biceps  can  be  seen  and  felt  the  ilio- 
tibial  band.  It  is  difficult  to  distin- 
guish the  joint-line  on  the  sides, 
therefore  it  is  better  to  locate  it  by 
recognizing  the  sulci  anteriorly  on 
each  side  of  the  tendo  patellae;  flex- 
ing the  knee  makes  these  depres- 
sions more  distinct.  The  joint  on 
the  outer  side  is  about  2  cm.  (^  in. ) 
above  the  head  of  the  fibula. 

Posteriorly,  with  the  leg  ex- 
tended, the  condyles  of  the  femur  can  readily  be  outlined;  the  inner  is  the  more 
prominent.  The  upper  edge  of  their  articular  surfaces  can  be  felt  on  firm  pressure 
at  the  sides,  and  the  inner  leads  to  the  adductor  tubercle,  into  which  the  adductor 
magnus  tendon  is  inserted — this  tendon  can  likewise  frequently  be  felt.  The  tubercle 
of  the  tibia  can  best  be  seen  and  felt  when  the  tendo  patellae  is  relaxed.  It  is  about 
4  cm.  {1)4  in.)  below  the  patella.  Just  above  and  to  its  outer  side,  about  4  cm. 
(i^  in.)  distant,  is  the  external  tuberosity  of  the  tibia;  into  it  is  inserted  the  lower 
end  of  the  iliotibial  band.  To  the  outer  side  at  a  little  lower  level  can  be  seen  and 
felt  the  head  of  the  fibula.  On  the  inner  side  is  the  flat  rounded  internal  tuberosity 
of  the  tibia.  Posteriorly  is  seen  the  fulness  of  the  popliteal  space;  on  its  outer  side 
the  tendon  of  the  biceps  is  readily  felt  and  running  with  it  is  the  external  popliteal 


Head  of  fibula 


-Patella 


Groove  of 
"  joint  line 

Internal 

-  tuberosity 

of  tibia 

Tibial 
tubercle 


Fig.  543. — Surface  anatomy  of  the  knee. 


534 


APPLIED    ANATOMY. 


or  fibular  nerve;  on  the  inner  side  the  most  prominent  tendon  is  the  semitendinosus 
with  the  semimembranosus  beneath  and  the  gracihs  to  the  inner  side. 


THE   KNEE-JOINT. 

As  the  functions  of  the  lower  extremity  are  support  and  mobility,  it  is  evident 
that  in  order  to  obtain  mobility  without  unduly  weakening  the  limb  the  ligament- 
ous connection  of  the  bones  must  be  exceptionally  strong.  The  knee  is  placed 
half  way  down  the  extremity,  hence  it  has  the  bulk  of  the  body  above  to  support  ; 
also,  the  bones  on  each  side  of  the  joint  are  the  longest  in  the  body,  hence  their  lever 
action  is  exceptionally  great,  which  likewise  necessitates  that  the  joint  be  firmly  braced 
by  ligaments. 

The  Movements  of  the  Knee. — The  knee  is  primarily  a  hinge-joint;  its  main 
movements  are  extension  and  flexion.      It  can  be  extended  to  a  straight  line  (i8o 

degrees)  and  flexed  until  the  thigh 
and  upper  portion  of  the  leg  come 
in  contact,  at  about  45  degrees  or  even 
less.  The  movement  is  a  combined 
gliding  and  rolling  one.  According 
to  Morris  ("  Joints,"  p.  375),  as  ex- 
treme extension  ends  the  leg  rotates 
a  little  outward  through  a  longitudi- 
nal axis,  passing  through  the  middle 
of  the  outer  condyle  of  the  femur,  and 
as  flexion  begins  it  rotates  inward. 
These  rotatory  movements  are, 
however,  slight,  and  may  practically 
be  ignored.  When  flexion  has  pro- 
ceeded to  150  or  155  degrees,  the  joint 
becomes  comparatively  loose,  and 
this  increases  as  the  joint  is  flexed, 
until  a  rotation  of  36  degrees  (Morris) 
is  allowed.  This  is  of  decided  prac- 
tical importance  because  injuries  and 
treatment  are  intimately  associated 
with  the  presence  of  rotatory  move- 
ments. No  rotation  is  possible  when 
the  knee  is  fully  extended,  the  bones 
being  then  immovable. 

Bones  of  the  Knee-joint. — 
The  knee-joint  is  between  the  femur, 
the  tibia,  and  the  patella;  the  fibula 
does  not  enter  into  it  (Fig.  544).  The 
patella  is  only  a  sesamoid  bone  de- 
veloped in  the  quadriceps  tendon,  and 
is  not  essential.  In  some  of  the  lower 
animals  it  has  a  synovial  membrane 
separate  from  the  knee-joint  proper. 
The  joint  between  the  femur  and 
tibia  is  built  up  of  two  separate  lateral 
parts;  the  condyle  and  tuberosity  of 
each  side  forming  practically  a  sepa- 
rate joint  and  having  a  crucial  liga- 
ment as  one  of  its  lateral  ligaments. 
The  object  of  thus  combining  two 
joints  side  by  side  to  form  one  joint  is  to  add  to  its  strength  and  lateral  stability. 
The  condyles  of  the  femur  have  their  articular  surfaces  prolonged  up  on  its  anterior 
surface,  not  to  aid  in  flexion  and  extension,  but  simply  to  facilitate  the  action  of  the 
patella.     The  outer  condyle  is  the  higher,  to  prevent  external  luxation  of  the  patella. 


Line  of  epiphysis 


External  condyle 

Patella 

Internal  tuberosity 

External  tuberosity 


Head  of  fibula 
Line  of  epiphyses 


7fT—  Tibial  tubercle 


Fig.  S44- — Antero-extemal  view  of  the  bones  of  the  knee. 


REGION    OF   THE   KNEE. 


535 


Patella 


The  articular  surfaces  of  the  condyles  are  not  perfect  arcs  of  a  circle.  If  they  were 
the  motion  would  be  solely  a  gliding  one  and  the  lateral  ligaments  and  crucial  liga- 
ments would  be  equally  tense  in  all  positions,  which  is  not  the  case,  for,  particularly  in 
flexion,  they  become  slightly  relaxed.  The  upper  surface  of  the  tibia  is  slightly 
hollow  and  its  spine  projects  upward  between  the  condyles,  thus  adding  to  the 
lateral  stability  of  the  joint. 

The  patella  is  divided  by  a  longitudinal  ridge  into  two  articular  facets,  the  outer 
for  the  external  condyle  being  the  larger;  the  ridge  lies  in  the  intercondylar  space. 
The  inner  part  of  the  patella  is 
thicker  than  the  outer  because 
the  inner  condyle  is  lower.  The 
patella  is  a  sesamoid  bone  which 
is  developed  more  toward  the 
deep  surface  of  the  tendon  of  the 
quadriceps.  The  tendon  goes 
over  the  surface  of  the  patella 
and  is  practically  continued 
longitudinally  through  the  su- 
perficial portion  of  the  bone.  If 
the  dried  specimen  is  hammered 
the  bone  can  be  pulverized  and 
removed,  leaving  the  tendon  of 
the  quadriceps  continuous  with 
the  tendo  patellae.  For  this  rea- 
son, when  the  patella  frac- 
tures, the  torn  fibrous  fringes 
are  never  on  the  articular  sur- 
face but  always  on  its  superficial 
surface.  The  patella  has  its 
sharp  apex  below  and  fractures 
frequently  tear  it  off,  the  small 
size  of  the  fragment  making 
repair  difficult. 

Ligaments  of  the  Knee- 
joint. — To  provide  for  the  sup- 
port required  to  be  given  by 
the  lower  extremity,  the  liga- 
ments and  tendons  binding  the 
bones  of  the  knee  together 
are  both  numerous  and  strong. 
The  bond  of  union  is  so  strong 
that  dislocations  from  traumatic 
causes  are  comparatively  rare, 
and  it  is  only  when  the  ligaments 
have  been  weakened  by  disease 
that  subluxations  take  place. 

The  knee  possesses  the  usual  capsular  ligament  but  so  hidden  by  strengthening 
bands  and  tendinous  expansions  that  but  little  of  it  is  seen.  Anteriorly  the  capsule 
is  strengthened  by  the  tendon  of  the  quadriceps,  the  patella,  and  the  tendo  patellae 
(Fig.  545).  Viewing  these  structures  as  a  whole  we  see  that  their  lower  end  is  firmly 
attached  at  the  tibial  tubercle,  but  above  their  attachments  are  far  removed  from  the 
joint.  They  are  so  strong  and  thick  that  pus  from  within  does  not  tend  to  go  through 
but  goes  around  them.  Their  upper  attachment  is  muscular,  so  they  do  not  act  to 
restrain  movements  except  when  the  muscle  is  contracted;  hence  flexion  is  limited 
by  contact  of  the  soft  parts  posteriorly  rather  than  by  tension  of  the  ligaments  ante- 
riorly. In  complete  extension  the  bulk  of  the  patella  rises  above  the  articular  sur- 
face, and  connecting  its  upper  edge  with  the  anterior  surface  of  the  femur  is  only  the 
thin  capsular  ligament,  hence  effusions  into  the  joint  bulge  upward  at  this  point. 
Extending  about  5  cm.  (2  in, )  above  the  patella  is  the  subfemoral  bursa;  this  in  8  out 


Fig.  S45-- 


-Knee- joint  distended  with  wax,  showing  the  extent  ot  its 
cavity  and  capsular  ligament. 


APPLIED    ANATOMY. 


of  lo  cases  communicates  with  the  joint,  and  effusions  readily  distend  it.  The  patella^ 
normally  lies  in  contact  with  the  femur  but  when  there  is  effusion  in  the  joint  it  is 
pushed  or  raised  up  and  is  called  a  floating  patella.  Pressure  on  it  causes  it  to  strike 
on  the  femur  beneath,  which  is  readily  felt  and  enables  one  to  diagnose  effusions 
within  the  joint.  Posteriorly  the  capsule  is  thick,  being  strengthened  by  an  expan- 
sion, called  the  posterior  ligament  or  ligamentum  Winslowii,  which  goes  upward 
and  outward  from  the  tendon  of  the  semimembranosus  muscle  at  the  upper  edge 

of  the  tibia.  It  is  pierced  by  the  branches 
of  the  azygos  articular  artery.  The  cap- 
sular ligament  is  weak  below  at  the  margin 
of  the  tibia  and  here  pus  may  find  an  exit. 
It  is  less  liable  to  come  out  above,  but 
the  bursa  under  the  inner  head  of  the  gas- 
trocnemius frequendy  (17  per  cent,  Mac- 


Tendon  of 

adductor 
magnus 


Tibial  tubercle 


Cut  edge  of 
capsule 


Biceps 


Long  external 
lateral  ligament 
Outer  head  of 
gastrocnemius 
Short  external 
lateral  ligament 

External  semi- 
lunar cartilage 


Fig.  546. — View  of  the  inner  side  of  the  knee- 
joint;  the  capsule  has  been  cut  away  from  the  edge 
of  the  patella  to  the  internal  lateral  ligament,  ex- 
posing the  interior  of  the  joint. 


Fig.  547. — ^View  of  the  outer  side  of  the  knee-joint. 
The  capsule  has  been  cut  away  from  the  edge  of  the 
patella  to  the  external  lateral  ligament. 


alister)  communicates  with  the  joint  and  is  usually  the  origin  of  the  ganglion  so  often 
seen  in  the  popliteal  region.  When  the  joint  becomes  subluxated  by  disease  the  tibia 
is  drawn  backward  and  this  posterior  capsular  ligament  may  shorten  and  prevent 
reposition  forward.  So  strong  is  it  that  forcible  attempts  are  liable  to  cause  fracture. 
Internally  the  capsular  ligament  is  strengthened  by  the  lateral  expansion  from 
the  side  of  the  patella  and  from  the  fascia  lata  over  the  vastus  internus;  these 
go  to  the  inner  tuberosity  of  the  tibia  and  strengthen  the  lower  part  of  the  joint, 


REGION    OF   THE    KNEE. 


537 


but  toward  the  upper  edge  of  the  internal  condyle  the  capsule  is  again  thin  and 
effusions  puff  it  out  at  that  point. 

Internal  Lateral  Ligament. — A  band  of  the  capsule  to  which  the  name  internal 
lateral  ligament  has  been  applied  runs  from  beneath  the  adductor  tubercle  to  the  tibia 
below  the  internal  tuberosity;  it  is  strengthened  by  fibres  from  the  tendon  of  the 
semimembranosus  and  has  the  internal  articular  vessels  and  nerves  passing  between 
it  and  the  tibia.  It  will  be  noted  that  it 
lies  toward  the  posterior  portion  of  the 
joint,  hence  it  limits  extension  (Fig.  546). 

Externally  the  capsule  has  likewise 
the  fibrous  expansion  of  the  quadriceps 
from  the  side  of  the  patella  and  the 
fascia  lata.  This  latter  is  the  strong 
iliotibial  band  and  goes  downward  to 
insert  into  the  outer  tuberosity  of  the 
tibia  (Fig.  547). 

External  Lateral  Ligameyits.  — 
There  are  likewise  two  band-like  liga- 
ments on  the  outer  side,  the  long  and 
short  external  lateral  ligaments.  The 
long  external  lateral  ligament  arises  from 
a  tubercle  just  below  and  in  front  of  the 
outer  head  of  the  gastrocnemius  muscle. 
It  is  about  5  cm.  (2  in.)  long  and  is 
attached  below  to  the  fibula,  anterior  to 
its  styloid  process.  It  is  embraced  on 
each  side  by  the  split  tendon  of  the 
biceps.  Beneath  it  pass  the  popliteus 
tendon  in  its  sheath  and  the  inferior  ex- 
ternal articular  vessels  and  nerve.  Note 
that  this  is  likewise  at  the  posterior  por- 
tion of  the  joint  and  therefore  it  too 
limits  extension. 

The  short  or  posterior  of  the  two 
external  lateral  ligaments  is  often  not  to 
be  recognized  as  a  distinct  structure,  it 
passes  from  the  styloid  process  of  the 
fibula  over  the  popliteus  tendon  to  blend 
with  the  posterior  capsular  ligament  on 
the  external  condyle.  The  lateral  liga- 
ments check  extension  and  outward  ro- 
tation of  the  tibia. 

Crucial  Ligameyits.  —  These  pass 
from  the  tibia,  the  anterior  being  at- 
tached in  front  of  and  the  posterior  be- 
hind the  spine,  upward  to  the  intercon- 
dylar notch  of  the  femur.  The  anterior 
or  external  passes  upward,  outward,  and 
backward.  The  posterior  or  internal 
passes  upward,  inward,  and  forward  (Fig.  548) .  They  are  never  very  lax  in  any  position 
of  the  joint,  but  the  anterior  is  most  tense  in  extension  and  the  posterior  in  flexion. 
The  anterior  tends  to  prevent  displacement  of  the  tibia  forward  and  the  posterior  liga- 
ment displacement  of  the  tibia  backward.  The  posterior  crucial  ligament  blends  with 
the  posterior  capsule  and  in  resecting  the  knee  care  should  be  taken  in  dividing  this 
ligament  that  the  popliteal  artery  is  not  wounded.  A  ligamentous  band  runs  from  the 
posterior  crucial  ligament  to  the  external  semilunar  cartilage ;  it  is  called  the  ligaineni 
of  Wrisberg.  The  knee-joint  in  some  of  the  lower  animals  is  composed  of  two  sepa- 
rate joints,  one  for  each  condyle,  and  the  crucial  ligaments  of  man  are  simply  the 
remains  of  lateral  ligaments  when  separate  joints  exist.     They  check  inward  rotation. 


Fig. 


548. — ^The  crucial  ligaments  exposed  by  sawing  off 
the  inner  surfaces  of  the  femur  and  tibia. 


S3? 


APPLIED    ANATOMY. 


Semihinar  Cartilages,  Coronary  and  Transverse  Ligaments. — The  semilunar 
cartilages  are  used  to  deepen  the  joint  in  the  same  manner  as  the  cotyloid  of  the  hip 
and  glenoid  of  the  shoulder.  It  is  their  method  of  attachment  that  is  important.  The 
external  is  nearly  circular,  the  internal  is  semi-elliptical.  The  ends  are  fibrous  and 
are  attached  in  front  of  and  behind  the  spine  of  the  tibia.  The  transverse  ligament 
is  a  band  passing  across  the  front  from  one  semilunar  cartilage  to  the  other  (Fig. 
549)  As  Macalister  has  pointed  out,  there  is  no  true  coronary  ligament.  It  is 
the  part  of  the  capsular  ligament  running  from  the  semilunar  cartilages  to  the  tibia. 

The  semilunar  cartilages  are  attached  by  their  outer  edges  to  the  capsular  liga- 
ment. This  attachment  is  less  in  extent  in  the  case  of  the  external,  because  its 
outer  surface  is  obliquely  grooved  by  the  tendon  of  the  popliteus  muscle,  but  it  has 
an  additional  attachment  in  the  ligament  of  Wrisberg,  as  stated  under  the  posterior 

crucial  ligament.     Humphry  ("Hu- 
man Skeleton, ' '  546)  has  pointed  out 
/  %i  that  the  semilunar  cartilages  in  flexion 

/'  ^  and  extension  move  with  the  tibia,  but 

in  pronation  and  supination  (rotation) 
move  with  the  femur. 

Ligamenta  Alaria  and  M71C0- 
sjini. — Below  the  patella  is  a  pad  of 
fat  extending  under  the  upper  portion 
of  the  tendo  patellae ;  a  bursa  is  under 
the  lower  portion.  Passing  up  from 
this  pad  to  the  intercondyloid  notch 
and  crucial  ligaments  is  the  ligamen- 
tum  mucosum;  below,  it  is  continu- 
ous with  the  synovial  fringes  at  each 
side  of  the  lower  edge  of  the  patella 
which  form  the  ligamenta  alaria. 
We  would  suggest  that  it  is  possible 
that  these  ligaments  perform  for  the 
knee-joint  what  AUis  has  suggested 
the  ligamentum  teres  does  for  the  hip, 
viz. :  act  as  a  swab  to  distribute  the 
synovia  over  the  articular  surfaces. 

Bursae  of  the  Knee. — There 
are  a  number  of  bursae  about  the 
knee-joint,  but  they  are  not  all  of  im- 
portance. Anteriorly  there  are  the 
prepatellar,  suprapatellar,  and  deep 
and  superficial  infrapatellar. 

The  prepatellar  hnrsdi  lies  in  the 
subcutaneous  tissue  between  the  skin 
and  patella.  It  is  often  enlarged,  con- 
stituting "housemaid's  knee"  (Fig. 
550).  The  bursa  is  almost  always 
present,  but  often  irregular  in  shape  and  character.  Injuries  frequently  cause  it  to 
inflame,  as  do  also  rheumatoid  affections.  Sometimes  the  tendon  of  the  quadriceps 
over  the  patella  is  ossified  clear  to  the  surface,  which  is  often  irregular  and  rough, 
and  is  felt  immediately  beneath  the  skin  with  apparently  no  subcutaneous  tissue 
intervening.  In  these  cases  the  bursa  may  be  very  irregular  or  loculated  in  shape, 
or  there  may  be  more  than  one.  The  sac  of  the  bursa  is  usually  very  thin,  but  be- 
comes thick  and  distinct  as  the  result  of  irritation.  Excision  is  usually  the  quickest 
way  of  curing  housemaid's  knee,  but  often  the  easier  way  of  simple  incision  and 
drainage  with  a  wick  of  gauze  is  sufificient. 

The  suprapatellar  or  subfemoral  bursa  extends  from  5  to  7.5  cm.  (2  to  3  in. ) 
above  the  patella  beneath  the  crureus  muscle.  It  is  liable  to  be  injured  by  stabs  or 
punctures,  and  thereby  infect  the  joint  with  which  it  communicates  in  8  out  of  10 
cases.      It  becomes  distended  in  intra-articular  efiusions. 


Subfemoral 

'  bursa 


Ridge  on 

Iiatella 


Ligamentum 
alaria 

Ligamentum 
mucosum 
Transverse 
ligament 
Internal  semi- 
lunar cartilage 
External  semi- 
lunar cartilage 
Anterior  cru- 
cial ligament 

Posterior  cru- 
cial ligament 

-Popliteus 


Head  of  fibula 


Semimem- 
branosus 


Fig.  S49- — View   of  the  interior  of  the  knee-joint,  looking 
forward. 


REGION   OF   THE    KNEE.  539 

The  infrapatellar  bitrscs  are  one  between  the  skin  and  tibial  tubercle  and  the 
other  between  the  under  surface  of  the  tendo  patellae  and  the  upper  end  of  the  tibia — 
they  are  unconnected  with  the  joint  and  are  not  often  diseased. 

Posteriorly.  — On  the  oictcr  side  of  the  joint  there  may  be  present  ( i )  a  bursa 
beneath  the  external  head  of  the  gastrocnemius  which  may  communicate  with  the 
bursa  between  the  popliteus  tendon  and  external  lateral  ligament.  (2)  One  be- 
tween the  biceps  tendon  and  external  lateral  ligament,  (3)  another  between  the  pop- 
liteus tendon  and  external  lateral  ligament,  and  (4)  one  beneath  the  popliteus, 
usually  an  extension  of  the  synovial  membrane  of  the  joint.  On  the  inner  side  : 
(i)  one  beneath  the  internal  head  of  the  gastrocnemius,  which  usually  commu- 
nicates with  the  joint  and  sends  a  prolongation  between  the  gastrocnemius  and  the 
semimembranosus.  This  is  the  most  important  posterior  bursa.  (2)  There  is  one 
beneath  the  tendons  of  the  sartorius,  gracilis,  and  semitendinosus  muscles.  (3)  One 
beneath  the  tendon  of  the  semimembranosus,  between  it  and  the  tibia;  it  rarely 
communicates  with  the  knee-joint.  (4)  One  between  the  tendons  of  the  semimem- 
branosus and  the  semitendinosus. 

Ganglion. — Sometimes  a  rounded  tumor  that  is  called  a  ganglion  appears  in  the 
popliteal  space.  When  the  knee  is  flexed  it  is  felt  as  a  round,  movable  tumor  which 
is  hard  and  cystic.  If  the  knee  is  extended  it  slides  inward  to  the  edge  of  the  inner 
condyle  and  becomes  hard  and  fixed.  It  usually  originates  from  the  bursa  beneath 
the  inner  head  of  the  gastrocnemius, 
is  prolonged  between  it  and  the  semi- 
membranosus, and,  when  the  knee  is 
flexed,  it  either  disappears  entirely  by 
its  contents  going  into  the  joint  or  it 
can  still  be  felt  in  the  popliteal  space. 
It  may  be  a  difificult  matter  to  excise 
these  cysts  on  account  of  their  ramifi- 
cations, and  when  this  is  impossible  it 
is  better  to  open  them  up,  clean  them 
out,  and  then  sew  the  wound  shut 
in  order  to  avoid  infecting  the  joint. 
Care  should  be  taken  not  to  mistake 
them  for  solid  tumors  or  enlarged 
lymph-nodes,  both  of  which  are  less 
common  than  ganglion. 

Fracture    of  the    Patella. — 

<T«t-  i.   11  u      r        4-         J    •       i-  Fig.  550. — Housemaid's  knee  or  enlargement  of  the  prepatel- 

The  patella  may  be  fractured  m  two  ^^  lar  bursa. 

ways,  producing  different  lesions  and 

requiring  different  treatment.      Fracture  is  produced  either  by  muscular  contraction 

or  by  direct  violence  ;  the  former  is  the  more  common. 

Fradicre  by  Indirect  Violence. — As  pointed  out  by  Humphry,  when  the  knee 
is  fully  flexed  only  the  upper  third  or  fourth  of  the  articular  surface  of  the  patella  is 
in  contact  with  the  condyles  of  the  femur — the  remaining  two-thirds  or  three-fourths 
of  the  projecting  portion  of  the  bone  resting  on  the  pad  of  fat.  When  semi-flexed 
the  greater  part  of  its  surface  is  in  contact  with  the  condyles,  or  at  least  the  whole  of 
its  middle  third.  In  full  extension  only  the  lower  third  or  fourth  or  even  less  remains 
in  contact. 

When  semi-flexed  the  patella  is  subjected  to  the  greatest  leverage  strain;  hence 
it  is  that  fractures  most  often  occur  in  this  position  and  that  the  fracture  occurs  so 
frequently  at  the  junction  of  the  lower  and  middle  portions.  When  the  bone  is  frac- 
tured by  indirect  force  (muscular)  the  line  of  fracture  traverses  its  whole  thickness 
and  consequently  the  joint  is  always  involved.  Usually  there  are  but  two  fragments. 
The  extent  of  separation  depends  on  the  amount  of  laceration  of  the  capsule  on  each 
side  of  the  line  of  fracture  (Fig.  551). 

On  each  side  of  the  patella  the  fibrous  expansion  of  the  quadriceps  tendon,  fascia 
lata,  and  joint  capsule,  if  intact,  will  prevent  separation  of  the  fragments.  If  it  is  rup- 
tured widely  it  will  permit  a  separation  of  about  2.5  cm.  (i  in.).  It  is  rare  that  the 
primary  injury  produces  a  wider  separation,  and  those  cases  in  which  the  fragments 


540 


APPLIED    ANATOMY. 


are  wider  apart  are  usually  those  in  which  the  upper  fragment  has  been  subsequently 

pulled  up  by  the  contraction  of  the  quadriceps.      A  fracture  which  when  recent  may 

have  had  only  i   cm.  separation  may  subsequently  show  7.5  to  10  cm.  (3  104  in.). 

When  the  union  is  fibrous  subsequent  stretching  may  occur,  also  refracture  increases 

the  tendency  to  wide  separation. 

Fracture  by  direct  violeyice  is  due  to  the  direct  impact  of  a  blow  or  a  crushing  of 

the  patella  between  the  femur  and  some  foreign  body.      In  this  case  the  capsule  on 

the  sides  is  but  little  torn  and  although  there  may  be  several  fragments  they  do  not 

become  widely  separated. 

Macevven  has  pointed  out  that  the  torn  fibrous  portion  of  the  quadriceps  over 

the  patella  may  hang  down  between  the  fragments  and  hinder  union. 

T?-eatmcnt. — The  method  of  treatment  to  be  employed  varies  according  to  the 

character   of  the  injury.       When   the  fracture  is  from  indirect  force,    means  must 

be  employed  not  only  to  hold  the  fragments  to- 
gether, but  also  to  repair  the  rent  in  the  capsule. 
Obviously  the  limb  is  to  be  kept  in  the  extended 
position  to  relax  the  quadriceps.  The  rectus,  on  ac- 
count of  taking  its  origin  from  the  pelvis,  is  also  to  be 
relaxed  by  elevating  the  limb.  A  common  method 
of  treatment  is  by  open  operation.  First  a  flap  is 
raised,  exposing  the  fracture,  then  the  fragments 
are  approximated  with  wire  or  other  sutures  and 
the  rent  in  the  capsule  closed  with  chromic  catgut 
or  silk. 

In  fractures  by  direct  violence,  when  separa- 
tion is  not  marked,  the  lateral  fascial  expansion  re- 
mains untorn  and  no  open  operation  is  necessary  ; 
in  others,  when   separation   is  more  marked,  and 

\<//  ''^    ■!  especially  if  the  fracture  is  compound,  a  flap  may 

0/  ^B    mi  be  turned  back  and  the  patella  surrounded  with  a 

f  ^^B  wM  strong  suture  of  chromic  gut  or  silk  and  the  frag- 

j^^/^^  ments  thereby  drawn  together;  the  suture  may  also 

be  introduced  subcutaneously. 

By  open  operation  the  blood  and  clots  which 
usually  fill  the  joint  can  be  removed  as  well  as  any 
fibrous  tissue  from  the  tendon  of  the  quadriceps 
which  may  lie  between  the  fragments. 

Dislocation  of  the  Patella. — The  articular 
surface  of  the  patella  is  divided  by  a  longitudinal 
ridge  into  an  outer  and  inner  part,  which  articulate 
with  the  corresponding  condyles  of  the  femur. 
The  outer  surface  for  the  external  condyle  is  much 
the  larger.  The  outer  condyle  is  also  much  higher  than  the  inner  and  thus  tends 
to  prevent  luxations.  The  lateral  fibrous  expansions  on  each  side  of  the  patella  also 
help  to  hold  it  in  place. 

Favoring  dislocation  is  the  inclination  inward  of  the  knee  and  the  oblique  pull 
of  the  quadriceps.  When  a  person  is  standing  upright  with  the  feet  together  the 
femurs  diverge  from  the  knee  as  they  approach  the  hip,  the  knees  forming  an  angle 
of  165  degrees  with  its  apex  in.  When  the  quadriceps  muscle  contracts  it  tends 
to  straighten  this  angle  and  so  pull  the  patella  out.  If  the  ligaments  are  normal 
and  the  pull  not  too  violent,  luxation  does  not  occur.  When,  however,  from  long 
disuse  or  disease  the  ligaments  become  relaxed,  then  a  sudden  and  perhaps  unusual 
contraction  of  the  quadriceps  will  dislocate  the  patella.  This  also  occurs  if  the  outer 
condyle  is  abnormally  flat  or  if  the  muscular  contraction  lifts  the  patella  off  or  above 
the  condyles,  as  occurs  when  the  tendo  patellae  is  too  long.  In  these,  as  in  almost  all 
other  cases,  the  patella  is  dislocated  outward  (Fig.  552).  Inward  dislocation  is  almost 
unknown.  Direct  injury  also  produces  dislocations,  practically  always  outward.  The 
most  common  form  is  for  the  articular  surface  of  the  patella  to  rest  on  the  outer  sur- 
face of  the  external  condyle.     Other  forms,  which  are  more  rare,  are  for  the  inner 


Fig.   SSI. — Fracture  of   patella,   showing 
lateral  tear  of  capsule. 


REGION    OF   THE    KNEE. 


541 


Fig.  552. — Dislocation  of  patella  outward. 


edge  of  the  patella  to  rest  against  the  outer  surface  of  the  condyle;  for  the  inner  edge 
to  be  jammed  into  the  upper  portion  of  the  intercondyloid  notch  with  its  outer  edge 
sticking  up;  for  the  patella  to  be  reversed  with  its  articular  surface  forward  and  its 
anterior  surface  resting  on  the  condyles. 

For  treating  the  affection  in  slight  cases  an  elastic  knee-cap  may  be  of  service, 
but  a  cure  is  probably  best  achieved  by  the  operation  of  Goldthwait  {^Boston  Med. 
andSiirg.  Joiirn.,  Feb.  13,  1904).  In  this  the  tendo  patellae  is  split  longitudinally 
and  its  outer  half  detached  from  the 
tibial  tubercle,  passed  under  the  remain- 
ing half,  and  sewed  fast  to  the  perios- 
teum and  expansion  of  the  sartorius  at 
the  inner  side  of  the  anterior  surface  of 
the  tibia.  This  shifts  the  pull  of  the 
quadriceps  more  inward  and  the  short- 
ening of  the  tendon  holds  the  outer 
edges  of  the  patella  more  firmly  against 
the  edge  of  the  external  condyle.  Simple 
folding  of  the  inner  part  of  the  capsule 
has  been  unsuccessful. 

Dislocation  of  the  Knee. — The 
knee  is  rarely  luxated  and  then  only  by 
such  extreme  trauma  as  sometimes  to 
rupture  the  popliteal  vessels  and  require 
amputation.  It  is  frequently  compound. 
The  tibia  may  be  luxated  anteriorly  (the 
most  frequent),  posteriorly,  to  either 
side,  or  it  may  be  rotated  on  the  femur. 
These  displacements  are  usually  due 
to  hyperextension  and  rotation.  The  laceration  of  the  surrounding  tissues  is  so  ex- 
tensive that  replacement  is  usually  easy  by  direct  traction  and  manipulation.  As  a 
result  of  weakening  of  the  ligaments  by  disease  the  hamstring  tendons  frequently  pull 
the  tibia  backward,  producing  a  subluxation  often  difficult  to  replace  (Fig.  553). 

Dislocation  of  the  Semilunar  Cartilages. — The  semilunar  cartilages  do  not 
become  displaced  in  their  entirety,  but  a  portion  of  one  of  them  is  torn  partly  or  com- 
pletely loose  and  in  moving  about  gets  caught  between  the  bones  and  produces  the 
characteristic  symptoms.     The  joint  becomes  useless  at  once  and  the  patient  may 

fall.  The  detachment  of  the  cartilage, 
which  is  usually  the  internal  one,  is 
caused  by  either  a  direct  blow  on  the 
part  or  by  a  twisting  of  the  partly  flexed 
limb.  Use  of  the  limb  cannot  be  re- 
sumed until  the  caught  cartilage  is  re- 
leased. This  is  most  readily  achieved 
by  extending  the  leg  and  then  sharply 
flexing  it.  Sometimes  the  loosened  car- 
tilage instead  of  remaining  attached  at 
one  end  is  free  in  the  joint  and  may 
make  its  appearance  alongside  of  the 
patella.  In  one  of  my  cases  one  end  of 
the  semilunar  cartilage  was  attached  to  the  crucial  ligament  while  the  other  was 
attached  to  the  capsular  ligament,  thus  allowing  the  part  between  to  stretch  across 
the  surface  of  the  condyle  and  be  compressed  in  walking.  These  floating  cartilages 
form  the  '''' gelenkniaiis^^  of  the  Germans.  These  two  conditions  were  first  described 
by  Hey  under  the  name  of  internal  derangements  of  the  knee-joint.  Synovial  disease 
may  also  produce  symptoms  closely  resembling  those  of  detached  cartilage. 

Epiphyseal  Separations. — The  epiphyseal  line  marking  the  lower  epiphysis 
of  the  femur  starts  at  the  adductor  tubercle,  at  the  upper  edge  of  the  internal  condyle, 
and  passes  across  transversely  just  above  the  edge  of  the  articular  surface.  It  joins 
with  the  shaft  between  the  twentieth  and  the  twenty-second  year,  sometimes  as  late  as 


Fig.  553. — Subluxa: 
disease,    showing   the   reiaiion    ui 
original  sketch  by  the  author.) 


■'.berculous 
(From  an 


542 


APPLIED    ANATOMY. 


the  twenty-fourth.  The  epiphysis  of  the  tibia  runs  transversely  across  the  tibia  about 
1.5  cm.  (^  in.)  below  the  articular  surface  and  anteriorly  passes  down  to  embrace 
the  tubercle  (Fig.  554). 

These  epiphyseal  separations  are  produced  either  by  direct  violence,  by  force 
applied  laterally,  or  by  twisting — a  common  way  is  for  the  leg  to  be  twisted  by  being 
caught  between  the  spokes  of  a  revolving  wheel.  They  nevei  occur  later  than  the 
age  of  twenty  years  and  usually  occur  several  years  before  that  age  has  been  reached. 

Often  the  displacement  is  not  serious 
and  is  corrected  before  the  patient  is 
seen  by  the  surgeon.  Occasionally, 
especially  when  the  lower  epiphysis  of 
the  femur  is  affected,  displacement  is 
marked,  and  the  fractured  surface  of 
the  fragment  may  lie  on  the  anterior 
surface  of  the  shaft  of  the  femur. 
Sometimes  the  injury  is  compound 
and  the  vessels  so  injured  that  ampu- 
tation is  required. 

In  spite  of  the  fact  that  the  greater 
part  of  the  growth  of  the  lower  ex- 
tremity occurs  from  the  bones  adja- 
cent to  the  knee-joint  epiphyseal  sep- 
arations almost  never  interfere  with  it. 
This  is  so  true  that  epiphysiolysis  or 
the  deliberate  separation  of  the  lower 
epiphysis  of  the  femur  by  bending  the 
knee  laterally  over  the  hard  edge  of 
a  table  is  the  preferred  operation  with 
some  surgeons  for  the  correction  of 
lateral  deformities  of  the  knee,  espe- 
cially knock-knee.  The  injury  is 
usually  treated  as  a  simple  fracture 
and  heals  without  incident. 

Resection  of  the  Knee. — In 
making  the  skin  incision  care  should 
be  taken  to  carry  it  back  sufficiently 
far  to  allow  of  division  of  the  lateral 
ligaments;  in  so  doing,  however,  one 
should  not  divide  the  long  saphenous 
vein  and  nerve  at  the  posterior  edge 
of  the  internal  condyle.  It  is  essen- 
tial to  recognize  the  joint-line;  it  is 
just  below  the  lower  edge  of  the  patella 
and  thence  extends  laterally  about  a 
finger-breadth  above  the  head  of  the 
fibula.  It  is  customary  to  carry  the 
incision  from  near  the  posterior  edge 
of  the  femur  on  the  inner  side  to  the 
posterior  edge  on  the  outer  side  at 
the  joint-line,  passing  over  the  middle  of  the  tendo  patellae  so  as  to  allow  this  latter 
to  be  readily  sutured  later  if  desired. 

Care  is  to  be  taken  to  avoid  wounding  the  popliteal  artery.  This  lies  close  to 
the  posterior  part  of  the  capsule;  hence  the  latter  is  not  to  be  divided  transversely 
but  is  to  be  separated  by  keeping  the  knife  close  to  the  bone.  Finally,  inasmuch  as 
the  bulk  of  the  growth  of  the  lower  extremity  occurs  in  the  upper  end  of  the  tibia 
and  lower  end  of  the  femur,  it  is  essential  to  avoid  removing  the  entire  epiphyseal 
cartilages.  For  this  reason  formal  resections  have  been  abandoned  in  young  children, 
and  in  adolescents  as  little  tissue  as  possible  is  removed.  The  epiphyseal  line  in  the 
femur  runs  transversely  on  a  line  with  the  adductor  tubercle  and  passes  close  to  the 


Line  of  epiphysis 


External  condyle 

Patella 

Internal  tuberosity 

External  tuberosity 


Head  of  fibula 
Line  of  epiphysis 


Tibial  tubercle 


Pig.  SS4. 


-Antero-extemal  view  of  the  bones  of  the  knee, 
showing  the  lines  of  the  epiphyses. 


REGION   OF  THE   KNEE. 


543 


upper  edge  of  the  articular  surface.  The  epiphyseal  line  in  the  tibia  lies  rather  close 
to  the  articular  surface,  being  1.5  cm.  (^  in.)  below  in  adults  and  less  in  children; 
it  slopes  down  in  front  to  embrace  the  tibial  tubercle  (see  Fig.  554).  When 
the  disease  encroaches  on  the  epiphyseal  line,  rather  than  remove  it  the  affected 
parts  are  to  be  curetted  away  and  the  remainder  left.  In  those  cases  where  the 
knee  is  much  contracted,  either  enough  of  the  bone  must  be  removed  to  allow  of 
straightening  or  the  hamstring  tendons  must  be  cut;  if  this  latter  is  done  the  external 
popliteal  nerve  which  runs  on  the  inner  posterior  surface  of  the  biceps  tendon  must 
not  be  wounded. 

Tuberculous  Disease  of  the  Knee-joint. — The  disease  begins  usually 
in  the  epiphyses  adjacent  to  the  joint  and  involves  the  joint  secondarily.  The 
tibia  is  more  frequently  the  seat  than  the  femur.  The  swelling  and  hypertrophy  of 
the  synovial  membrane  and  involvement  of  the  adjacent  soft  parts  obliterate  the 
hollows  on  each  side  of  the  patella  and  cause  a  bulging  below  the  patella.  The 
knee  looks  round  and  swollen,  and  the  condition  was  formerly  called  white  swelling 
from  the  surface  being  white  in  color.  If  liquid  accumulates  in  the  joint  it  becomes 
distended  and  flexed,  assuming  an  angle  of  120  de- 
grees. The  patella  is  raised  from  the  condyles;  it 
' '  floats ' '  and  if  depressed  by  the  finger  can  be  felt 
striking  on  the  femur  beneath,  thus  demonstrating 
the  presence  of  liquid  in  the  joint.  The  swelling 
extends  above  the  patella  to  an  extent  depending 
on  whether  or  not  the  subfemoral  bursa  is  involved 
and  whether  or  not  it  communicates  with  the  joint. 

If  pus  forms  it  tends  to  find  an  exit  beneath  the 
lower  edge  of  the  posterior  ligament  or  on  either  side 
of  the  patella  at  the  upper  end  of  the  tibia.  As  the 
disease  progresses  the  ligaments  become  weakened. 
The  joint,  being  already  flexed  at  approximately  1 20 
degrees,  is  flexed  still  more  by  the  hamstring  muscles, 
and  the  head  of  the  tibia  in  old  cases  becomes  drawn 
backward  in  a  position  of  subluxation  (see  Fig.  553, 
page  541).  The  pull  of  the  biceps  tendon  while  the 
leg  is  flexed  rotates  the  leg  outward  and  this  position 
may  persist:  a  condition  of  knock-knee  is  also  some- 
times marked. 

The  disease  is  treated  conservatively  by  appa- 
ratus, but  in  exceptional  cases  the  lesser  operation 
of  erasion  or  the  greater  of  resection  (see  above) 
is  done. 

Knock-knee  and  Bow-legs. — These  condi- 
tions most  frequently  result  from  rachitis  or  paralysis. 
Bowing  inward  of  the  knee  is  called  knock-knee  or 
genu  valgum.  Bowing  outward  is  called  bow-legs  or  in  some  instances,  when 
the  deformity  is  in  the  joint,  as  when  the  condyles  are  unequal  in  length,  genu 
varum. 

Knock-knee  {Genu  Valgum).  This  condition  has  its  point  of  bending  most 
marked  at  the  knee-joint.  When  caused  by  rickets  the  joint  surfaces  are  often  not 
much  altered  and  the  deformity  is  produced  by  a  bending  of  the  tibia  or  femur 
close  to  the  joint;  hence  when  an  osteotomy  is  performed  just  above  the  condyles 
of  the  femur  the  joint  is  again  brought  level  and  resumes  its  functions  normally 

(Fig-  555)- 

When  deformities  of  the  foot  or  the  malpositions  due  to  paralyses  produce 
knock-knee,  then  often  a  certain  amount  of  flexion  and  external  rotation  of  the  leg 
coexist  with  perhaps  lengthening  of  the  internal  condyle.  In  these  cases  osteotomy 
of  the  femur  must  often  be  supplemented  or  substituted  by  suitable  apparatus,  opera- 
tions on  the  foot,  etc. 

Bow-legs. — This  is  almost  always  caused  by  softening  of  the  bones,  as  in  rickets. 
The  bending  occurs  in  the  bones  of  both  the  leg  and  thigh,  and  the  location  of  the 


Fio.   SSS- — Knock-knee  or  genu  valgum. 


APPLIED   ANATOMY. 


point  of  greatest  bending  is  sometimes  low  down  toward  the  ankles  or  close" 

the  knee-joint,  or  the  whole  diaphysis  of  the  bones  may  be  curved.      They  are  often 

curved  anteroposteriorly  as  well  as  laterally  (Fig.  556). 

When  the  point  of  greatest  bending  is  close  to  the  knee-joint  it  has  been  called  . 
genu  varum,  but  the  condyles  remain  of  equal  length  and  the  epiphyseal  line  still 
remains  parallel  with  the  joint  line. 

As  knock-knees  and  bow-legs  so  commonly  occur  in  the  actively  growing  period, 
from  the  second  to  the  fifth  year,  apparatus  is  often  of  benefit,  but  frequently  forcible 
straightening  by  means  of  an  osteoclast  or  by  the  hand  or  epiphysiolysis  (see  page 
542)  or  osteotomy  is  resorted  to  for  their  correction. 

Osteotomy. — In  osteotomy  of  the  femur  the  bone  is  to  be  divided,  as  advised 
by  Macewen,  a  finger-breadth,  at  least,  above  the  adductor  tubercle  and  1.25  cm. 
{}4  in.)  in  front  of  the  adductor  magnus  tendon.      In  knock-knee  many  surgeons 

prefer  dividing  the  bone  from  the  outside  of 
the  limb  instead  of  the  inside  as  advised  by 
Macewen.  This  incision  avoids  the  epiphyseal 
line,  which  is  opposite  the  adductor  tubercle, 
and  also  the  anastomotica  magna  and  superior 
articular  arteries.  The  popliteal  vessels  are 
also  to  be  avoided  by  knowing  their  position 
and  not  directing  the  osteotome  toward  them. 
In  performing  osteotomy  of  the  bones  of  the 
leg  the  tibia  is  to  be  divided  by  the  aid  of 
the  chisel,  and  the  fibula  is  to  be  broken  by 
manual  force.  Wedge-shaped  resections  of 
bone  are  commonly  not  to  be  advised.  They 
are  difficult  to  do,  liable  to  complications,  and, 
under  the  most  favorable  circumstances,  are 
very  long  in  healing  and  do  not  give  any  better 
results  than  simple  osteotomy  or  osteoclasis. 
Ligation  of  the  Popliteal  Artery. — 
In  the  viiddle  of  its  course  the  popliteal  artery 
lies  deep  between  the  condyles  of  the  femur 
and  on  the  posterior  capsule  and  gives  of? 
the  articular  arteries.  For  these  reasons  liga- 
tion in  this  part  of  its  course  is  not  performed. 
To  ligate  it  in  the  tipper  part  of  its  course  an 
incision  is  to  be  made  along  the  outer  edge 
of   the   semimembranosus    muscle    near   the 

i_..™„. middle  of  the  upper  part  of  the  popliteal  space. 

Fig.  ss 6. —Bow-legs.  The  muscle  being  drawn  inward  the  internal 

popliteal  nerve  is  first  seen  and  drawn  outward, 
then  the  vein  beneath  is  also  drawn  outward  and  the  artery  found  beneath  and  a 
little  to  the  inner  side.  Don't  mistake  the  semitendinosus  for  the  semimembranosus. 
The  former  is  a  round  tendon,  the  latter  is  muscular.  Another  method  consists 
in  making  the  incision  immediately  behind  the  adductor  magnus  tendon.  The 
semimembranosus  and  semitendinosus  are  then  to  be  drawn  backward  and  the  artery 
located  by  its  pulsation  and  the  aneurism  needle  passed  from  within  out.  The  nerve 
and  vein,  being  more  to  the  outer  side,  are  not  disturbed  (Fig.  557). 

To  ligate  the  popliteal  artery  in  its  lower  third,  make  an  incision  in  the  midline 
between  the  heads  of  the  gastrocnemius  muscle,  avoiding  the  short  saphenous  vein 
and  nerve.  Open  the  deep  fascia,  draw  the  internal  popliteal  nerve  to  the  inner  side, 
the  popliteal  vein  to  the  outer  side,  and  pass  the  needle  from  without  in.  Flexing 
the  knee  will  relax  the  gastrocnemius  and  enable  the  artery  to  be  more  readily 
exposed. 

Amputation  through  the  Knee-joint. — Disarticulation  at  the  knee-joint  is 
usually  done  either  with  a  long  anterior  and  short  posterior  or  two  lateral  flaps. 
This  amputation  difJers  from  others  in  the  fact  that  a  large  rounded  mass  of  bone — 
the  condyles — with  no  muscles  is  to  be  covered  by  the  flap.     Therefore  the  flaps 


THE   LEG. 


545 


must  be  ample  and  if  they  are  not  a  piece  of  the  femur  must  be  resected.  The 
internal  condyle  is  larger  and  projects  more  than  the  external.  The  cicatrix  is  drawn 
posteriorly  by  the  hamstring  muscles  and  the  resultant  stump  is  good  for  pressure 
bearing. 

If  possible  the  semilunar  cartilages  should  be  left  on  the  femur,  the  incision  for 
disarticulation  being  made  between  them  and  the  tibia.  The  object  of  so  doing  is  to 
prevent  the  retraction  of  the  soft  parts  and  the  resultant  protrusion  of  the  bone.     The 


Semimembranosus  - 
Semitendinosus  - 


Internal  (long) 
saphenous  vein 

Internal  Hong) 
saphenous  nerve 


Internal  head  of 
gastrocnemius 


Short  saphenous  vein 


Popliteal  vein 
Popliteal  artery 


Plantaris 

Internal  popliteal 
(tibial)  nerve 

External  popliteal 
(fibular)  nerve 

Biceps 

Extemat  head  of 
gastrocnemius 


Peroneus  longus 


Communicans  fibularis 


Fig.  557. — The  popliteal  space. 


extremities  of  the  incision  should  be  well  back,  so  that  the  lateral  ligaments  can  be 
readily  divided,  and  should  not  extend  higher  than  the  edge  of  the  tibia.  If  infection 
follows,  pus  may  collect  in  the  suprapatellar  (subfemoral)  bursa. 


THE   LEG. 


The  leg  having  to  support  the  weight  of  the  body  has  its  bones  strongly 
made.  The  tibia  bears  nearly  all  the  weight  because  it  articulates  with  the  femur 
above  and  astragalus  below  and  transmits  the  pressure  directly  from  one  to  the 
other.  The  fibula  is  slight  compared  to  the  tibia  and  lies  posterior  to  it  and  to  the 
outer  side. 

The  leg  bones  receive  the  insertion  of  the  thigh  muscles  above  and  give  attach- 
ment to  the  muscles  which  move  the  foot.      The  leg  therefore  is  capable  of  being 
influenced  by  the  movements  of  the  foot  below  and  the  thigh  above. 
35 


APPLIED  ANATOMY. 


SURFACE  ANATOMY. 

At  the  upper  end  of  the  leg  can  be  feh  the  two  tuberosities  of  the  tibia.  The 
lower  edge  of  the  tuberosities  is  on  a  line  with  the  upper  edge  of  the  tubercle- 
The  head  of  the  fibula  is  almost  level  with  (a  little  above)  the  tubercle  of  the  tibia 
and  is  situated  far  posteriorly.  Attached  to  the  head  of  the  fibula  above  is  the 
biceps  tendon  accompanied  by  the  external  popliteal  (fibular)  nerve  and  the  long 
external  lateral  ligament.  The  tendo  patellae  is  attached  to  the  tibial  tubercle.  The 
tibia  is  triangular  in  shape,  with  a  sharp  edge — the  crest  or  shin — forward,  thus  form- 
ing two  surfaces,  an  internal  and  an  external.  The  posterior  surface  is  covered  by 
muscles  and  is  inaccessible.  The  internal  surface  is  subcutaneous  and  leads  down  to 
the  internal  malleolus.  The  external  surface  has  the  extensor  muscles  between  it 
and  the  fibula.     The  fibula  a  short  distance  below  its  head  becomes  covered  by  the 


/ 


Tendo  patelhi' 
External  tuberosity  of  tibia  - 
Head  of  fibula  - 
Tubercle  of  tibia  - 


Swell  of  anterior  tibial  muscle  - 

Intermuscular  space  - 

Swell  of  extensor  longus  digitorum  - 

Swell  of  peroneus  longus  and  brevis  - 

Crest  of  the  tibia - 


Fig.  ss8. — Surface  anatomy  of  the  leg. 


peronei  muscles  and  only  becomes  subcutaneous  in  its  lower  anterior  fourth.  The 
upper  portion  of  the  leg  is  largely  muscular,  but  at  its  lower  portion  it  is  mainly 
tendinous.  By  placing  a  finger  over  the  muscles  while  the  foot  is  moved  one  is 
enabled  to  determine  whether  or  not  they  are  paralyzed  (Fig.  558). 


MUSCLES   OF   THE   LEG. 


They 


The  muscles  of  the  leg  are  composed  of  four  distinct  groups  of  three  each, 
are  extensors^  flexors,  abductors,  and  muscles  of  the  calf. 

The  extensor  group  comprises  the  tibialis   anterior,  extensor  longus   digi- 
torum, and  extensor  longus  hallucis. 

The  flexor  group  comprises  the  tibialis  posterior,  flexo7~  longus  digitorum,  and 
flexor  longus  hallucis. 

The   abductor  group   comprises  the  peroneus  longus,  peroneus  brevis,  and 
t)€ro7ieus  tertius. 

The  calf  muscles  comprise  the  gastrocnemitis,  soleus,  and  plantaris. 


THE    LEG. 


547 


It  will  thus  be  seen  that  the  extensor  and  flexor  groups  are  composed  of  pre- 
cisely similar  muscles  only  on  opposite  sides  of  the  leg.  They  tend  to  move  the  foot 
and  toes  forward  and  backward  and  balance  each  other.     The  abductors  form  a  group 


Anterior  tibial 

Extensor  longus 
hallucis 
Extensor  longus 
digitorum 
Peroneus  tertius 
Peroneus  brevis 
Peroneus  longus 


Peroneus  tertius 
Peroneus  brevis 
Peroneus  longus 


■  Plantaris 

Inner  and  outer 
,  heads  of 
gastrocnemius 


Popliteus 


Soleus 


Gastrocnemius 


Flexor  longus 
■  digitorum 
Posterior  tibial 

Flexor  longus 
hallucis 

Tendo  calcaneus 
(Achillis) 


Fig.  559. — Extensor  and  abductor  muscles  of  the  leg.  Fig.  560. — Flexors  and  muscles  of  the  calf  of  the  leg. 


around  the  fibula  on  the  outer  side  of  the  leg  and  they  abduct  the  foot.  They  tend 
to  pronate  it.  The  most  active  agents  in  adduction  are  the  tibiaHs  anterior  and 
tibialis  posterior.     The  muscles  of  the  calf  form  a  separate  posterior  group  designed 


54? 


APPLIED    ANATOMY. 


for  use  in  walking  and  to  compensate  for  the  greater  length  of  the  foot  anterior  to  the 
centre  of  motion  at  the  ankle  and  its  shortness  posteriorly. 

The  extensor  group  lies  between  the  tibia  and  fibula  anterior  to  the  interosseous 
membrane.  The  abductor  group  forms  a  mass  over  the  fibula,  and  the  flexor  group 
lies  between  the  tibia  and  fibula  on  the  posterior  surface  of  the  interosseous  mem- 
brane. The  muscles  of  the  calf  constitute  a  superficial  layer  of  muscles  which  end 
below  in  the  tendo  calcaneus  (Achillis).  The  soleus,  with  the  two  heads  of  the  gas- 
trocnemius, is  known  as  the  triceps  surae  muscle.  It  is  absolutely  essential  to  under- 
stand the  grouping  of  these  muscles  of  the  leg  because  thereby  its  construction  is 
rendered  evident  and  their  influence  on  distortions  of  the  foot  can  be  appreciated. 

FASCIA   OF   THE   LEG. 

The  deep  fascia  of  the  leg  is  attached  above  to  the  tubercle  of  the  tibia,  the 
tuberosities  of  the  tibia,  and  the  head  of  the  fibula.  It  gives  off  two  septa  from  its 
under  surface,  one  in  front  separating  the  abductor  or  peroneal  group  from  the  exten- 
sor group,  and  another  posterior  which  separates  the  abductor  group  from  the  soleus 
posteriorly.  This  latter  covers  the  deep  flexors  and  separates  them  from  the  muscles 
of  the  calf  and  is  continued  across  to  be  attached  to  the  medial  (internal)  edge  of  the 
tibia.  The  deep  fascia  of  the  leg  blends  with  the  periosteum  over  the  medial  (inter- 
nal) surface  of  the  tibia  and  also  with  that  of  the  lateral  (external)  surface  of  the 
fibula  in  its  lower  fourth.  At  the  ankle  the  deep  fascia  is  continued  on  through 
the  annular  ligaments. 

The  muscles  of  the  leg  take  their  origin  partly  from  these  fasciae,  and  subsidiary 
septa  pass  between  the  muscles. 


Tibialis  anterior 
Anterior  tibial  artery- 
Anterior  tibial  nerve 
Extensor  longus  digitorum 


ARTERIES   OF   THE   LEG. 

The  leg  has  three  main  arteries,  the  anterior  tibial,  posterior  tibial,  and  per- 
oneal.    The  popliteal  artery  divides  into  the  anterior  and  posterior  tibial  at  the  lower 

border  of  the  popliteus  muscle  just  below 
the  lower  edge  of  the  tibial  tubercle. 

Two  and  a  half  cm.  (i  in. ),  or  a  little 
/  more,    below   the   edge   of   the   popliteus 

muscle  the  peroneal  artery  is  given  off  from 
the  posterior  tibial. 

The  Anterior  Tibial  Artery. — Li- 
gation.— The  line  of  the  anterior  tibial 
artery  may  be  taken  as  from  just  internal 
tp  the  head  of  the  fibula  to  a  point  on  the 
front  of  the  ankle  midway  between  the 
malleoli.  The  anterior  tibial  artery  pierces 
the  interosseous  membrane,  but  the  anterior 
tibial  nerve  winds  around  the  head  of  the 
fibula  and  joins  the  artery  5  to  7  cm.  (2  to 
3  in. )  or  more  lower  down  on  its  outer 
side. 

In  the  Upper  Third. — The  artery  lies 
between  the  tibialis  anterior  and  the  exten- 
sor longus  digitorum  muscles.  This  inter- 
space is  better  recognized  by  touch  than  by 
sight,  though  a  yellowish  line  of  fat  or  the 
presence  of  some  small  vessels  may  indi- 
cate its  position.  The  tendency  is  to  make 
the  incision  too  close  to  the  tibia.  This 
mistake  will  be  avoided  if  the  line  of  the  artery  has  been  marked  and  the  incision 
made  in  it.  After  separating  the  muscles,  the  outer  edge  of  the  tibia  can  be 
felt  and  on  the  membrane  close  to  it  is  the  artery  with  venae  comites  to  each  side  and 
the  nerve  farther  out.     The  needle  is  passed  from  without  inward,  and  the  veins  may 


Extensor  longus  hallucis 

Anterior  tibial  artery 

Tibialis  anterior 

Anterior  tibial  nerve 

Extensor  longus  digitorum 


Fig.   56 1. — Ligation  of  the  anterior  tibial  artery  in  its 
upper  and  lower  thirds. 


THE   LEG. 


549 


Line  for  posterior 
bial  artery 


Gastrocnemius 


be  included  because  they  are  so  firmly  bound  to  the  artery  and  membrane  as  to  be 
separated  only  with  difficulty  (Fig.  561). 

In  the  Middle  Third. — The  incision  having  been  made  in  the  line  of  the  artery, 
the  septum  between  the  tibialis  anterior  and  extensor  longus  digitorum  is  usually  vis- 
ible as  a  depressed  line.  Flex  the  foot  to  relax  the  tendons,  and  on  drawing  the 
extensor  digitorum  outward  the  upper  part  of  the  extensor  longus  hallucis  is  seen,  it 
also  is  drawn  outward  and  the  artery  is  found  lying  on  the  membrane  with  the  nerve 
in  front  of  it. 

hi  the  Lower  Third.  —  Here,  above  the  flexure  of  the  ankle,  the  artery  lies 
on  the  tibia  between  the 
tibialis  anterior  and  the 
extensor  longus  hallucis. 
The  nerve  is  to  its  outer 
or  inner  side  or  in  front 
of  the  artery.  Flexing  the 
foot  allows  the  tendons  to 
be  more  readily  separated, 
and  movement  of  the  foot 
and  big  toe  will  assist  in 
identifying  the  muscles. 

Posterior  Tibial 
hx\.&xy  .—Ligation.— T\iQ. 
line  of  the  posterior  tibial 
artery  is  from  the  middle 
of  the  popliteal  space  to 
the  middle  of  the  line  join- 
ing the  internal  malleolus 
and  internal  tuberosity  of 
the  calcaneum;  at  this  lat- 
ter point  it  divides  into 
the  internal  and  external 
plantar  arteries  (Fig.  562). 

hi  the  Middle  of  the 
Leg.  —The  incision  should 
be  made  2  cm.  (^  in.) 
behind  the  edge  of  the 
tibia,  avoiding  the  long 
saphenous  vein.  If  the 
edge  of  the  gastrocnemius 
comes  into  view  draw  it 
outward,  incise  the  soleus 
muscle  through  its  entire 
thickness,  dividing  the 
tendinous  fibres  in  the 
body  of  the  muscle.  Sep- 
arate the  edges  of  the 
incision  and  seek  for  the 
artery  on  the  obliquely 
running  fibres  of  the  flexor 
longus  digitorum  muscle. 
The  nerve  is  to  its  outer 
side.  The  artery  lies  di- 
rectly over  the  outer  edge  of  the  tibia,  which  can  be  felt  with  the  finger.  It  is  covered 
with  a  thin  fascia.      The  ligature  is  passed  from  without  inward. 

Low  Doivn  in  the  Leg. — The  incision  may  be  made  midway  between  the  inner 
edge  of  the  tibia  and  the  edge  of  the  tendo  calcaneus  (Achillis).  The  artery  lies 
beneath  the  deep  fascia  on  the  flexor  longus  digitorum  muscle  with  the  nerve  to  the 
outer  side.  The  muscle  has  fibres  as  low  down  as  the  malleolus  and  the  artery  is  to 
the  outer  side  of  its  tendon.      If  the  artery  is  sought  behind  the  ankle  then  it  has  the 


Soleus 


Posterior  tibial  artery 
Posterior  tibial  nerve 


Soleus 


Posterior  tibial  tendon 
Flexor  longus  digitorum 

Posterior  tibial  artery 
Posterior  tibial  nerve 


Internal  tuberosity  of  os  calcis 

Fig.  562. — Ligation  of  the  posterior  tibial  artery. 


5  so 


APPLIED   ANATOMY. 


tendons  of  the  tibialis  posterior  and  flexor  longus  digitorum  in  front  of  it.  Care  should 
be  taken  that  the  main  trunk  is  Hgated  and  not  one  of  its  plantar  branches  in  case  of 
a  high  division. 

Peroneal  Artery. — The  peroneal  artery  is  given  off  from  the  posterior  tibial 
2.5  cm.  (i  in.)  below  the  lower  edge  of  popliteus  muscle.  It  follows  the  inner  edge 
of  the  fibula  beneath  or  in  the  fibres  of  origin  of  the  flexor  longus  hallucis.  If  it  is 
desired  to  ligate  it,  the  incision  is  to  be  made  over  the  inner  edge  of  the  fibula,  the 
edge  of  the  soleus  is  drawn  inward,  the  fibres  of  the  flexor  longus  hallucis  divided, 
and  the  artery  found  at  the  junction  of  the  inner  edge  of  the  fibula  and  interosseous 
membrane.  At  the  lower  extremity  of  the  interosseous  membrane  the  artery  pierces 
it  to  be  distributed  to  the  outer  anterior  portion  of  the  tarsus  and  ankle. 


VEINS   OF   THE   LEG. 

The  deep  veins  of  the  lower  extremity  accompany  the  arteries.  The  femoral 
and  popliteal  veins  are  single,  but  the  arteries  below  have  venae  comites.     These  deep 

veins  all  have  valves  and  there  are  fre- 
quent communications  with  the  super- 
ficial veins. 

On  the  dorsum  of  the  foot  is  a 
venous  arch  which  unites  with  the  inner 
dorsal  digital  vein  to  form  the  commence- 
ment of  the  internal  or  long  saphenous 
vein.  The  outer  extremity  unites  with 
the  outer  dorsal  digital  \'ein  to  form  the 
commencement  of  the  external  or  short 
saphenous  vein. 

The  internal  or  long  saphenous 
vein  begins  just  in  front  of  the  inter- 
nal malleolus,  ascends  on  the  inner  sur- 
face of  the  tibia,  passes  along  the  poste- 
rior border  of  the  internal  condyle  and 
thence  up  to  the  saphenous  opening. 
In  the  leg  it  communicates  with  the  deep 
anterior  and  posterior  tibial  and  external 
saphenous  veins  and  in  the  thigh  with 
the  femoral.  At  or  near  the  saphenous 
opening  it  receives  the  external  super- 
ficial femoral  vein  from  the  outer  ante- 
rior surface  of  the  thigh  and  the  internal 
superficial  femoral  vein  from  the  inner 
posterior  portion  of  the  thigh.  Not  infre- 
quently one  of  these  lateral  branches  may 
be  almost  as  large  as  the  internal  saphe- 
nous itself  and  may  be  mistaken  for  it. 
From  the  knee  down  the  internal  saphenous  vein  is  accompanied  by  the  internal 
saphenous  nerve. 

The  external  or  short  saphenous  vein  begins  behind  the  external  malleolus, 
ascends  alongside  the  tendo  calcaneus  (Achillis),  thence  over  the  gastrocnemius  to 
empty  into  the  popliteal  vein.  Its  branches  anastomose  with  those  of  the  internal 
saphenous  on  the  inner  side  of  the  leg  and  it  communicates  through  the  deep  fascia 
with  the  deep  veins.      It  is  accompanied  by  the  external  saphenous  nerve. 

Varicose  Veins  of  the  Leg. — A  varicose  condition  of  the  veins  of  the  leg  is 
very  common.  Often  the  cause  cannot  be  ascertained,  but  not  infrequently  pelvic 
tumors,  and  especially  pregnancy,  produce  the  condition  by  obstructing  the  blood- 
current.  The  veins  become  distended  and  the  valves,  of  which  there  are  many, 
become  insufficient.  This  destroys  the  valvular  support  of  the  blood  column  and  the 
veins  become  tortuous  and  inflamed,  the  walls  thicken  and  may  become  adherent  to 
the  skin.    The  walls  in  places  give  way,  causing  hemorrhages.    They  may  become  thin 


Fig.  563. — Varicose  veins,  affecting  especially  the  inter- 
nal or  long  saphenous  vein. 


THE    LEG. 


551 


and  sacculated  and  thrombi  may  form  and  suppurate.  The  treatment  consists  in  ligat- 
ing  and  excising  as  many  of  the  affected  veins  as  possible.  The  internal  saphenous  is 
especially  to  be  excised,  beginning  a  short  distance  below  the  saphenous  opening  and 
extending  for  the  greater  portion  of  its  length  (Fig.  563). 

The  operation  of  Max  Schede,  of  circular  incision  around  the  leg  just  below  the 
knee,  dividing  everything  down  to  the  deep  fascia,  is  usually  effective,  but  we  have  seen 
recurrences  even  after  it,  due  to  regurgitation  from  the  deep  veins.  In  fat  people  the  in- 
ternal saphenous  may  lie  imbedded  in  the  superficial  fat  some  distance  beneath  the  skin. 

A  varicose  condition  of  the  veins  of  the  leg  is  a  causative  factor  in  chronic  leg 
ulcer;  hence,  in  order  to  cure  it,  the  necessity  of  elevating  the  limb  in  its  treatment, 
or  excising  the  veins. 

LYMPHATICS   OF   THE   LEG. 

Sometimes  there  are  one  or  two  lymphatic  nodes  at  the  upper  extremity  of  the 
anterior  tibial  artery  but  usually  the  first  to  be  encountered  are  around  the  popliteal 
vessels, — below  that  point  are  only 
lymphatic  radicles  or  vessels. 

FRACTURES   OF  THE  LEG. 

Fractures  of  the  bones  of  the  leg 
are  most  often  due  to  direct  violence, 
but  sometimes  to  indirect.  The  tibia 
is  rarely  broken  alone,  but  either  it 
or  the  fibula  may  be  fractured  by  a 
direct  blow.  On  account  of  the  tibia 
being  subcutaneous  these  fractures 
are  frequently  compound.  The  shafts 
of  the  bones,  being  of  compact  tissue, 
are  usually  broken  obliquely.  When 
the  fibula  is  broken  above  its  lower 
fourth  there  is  usually  little  displace- 
ment because  the  attached  muscles 
hold  it  in  place. 

Fractures  of  the  tibia  whether 
accompanied  or  not  by  fracture  of  the 
fibula  most  often  occur  at  the  junction 
of  the  middle  and  the  lower  thirds. 
The  line  of  fracture  is  downward,  for- 
ward, and  inward.  The  displacement 
of  the  lower  fragment  is  backward, 
upward  and  slightly  outward.  It  is 
produced  mainly  by  the  muscles  of 
the  calf  pulling  on  the  tendo  calcaneus 
(Achillis).  The  upper  fragment  is 
pulled  forward  by  the  quadriceps  fem- 
oris  (Fig.  564). 

The  difficulty  usually  encountered 
in  treatment  is  a  persistent  projecting 
forward  of  the  upper  fragment  with 
a  drawing  up  and  turning  outward  of 
the  lower  fragment  and  foot.  The 
displacing  action  of  the  tendo  cal- 
caneus (Achillis)  is  more  powerful 
than  that  of  the  quadriceps.  On  this 
account  the  first  attempt  at  correc- 
tion should  be  to  place  the  leg  in  the 
"  Pott's  position."  This  consists  in  flexing  the  knee  to  a  right  angle  and  placing  the 
leg  on  its  outer  side.     This  relaxes  the  gastrocnemius  and  plantaris  and  is  sufficient 


Plantaris 

Tendo  calcaneus  (Achillis) 

Posterior  tibial 

Flexor  longus  digitorum 

Flexor  longus  hallucis 


Fig.  564. — Fracture  of  the  tibia  with  displacement  ot 
the  upper  fragment  forward  and  lower  fragment  backward 
and  upward. 


552 


APPLIED    ANATOMY. 


in  some  cases  to  allow  of  the  displacement  being  remedied.  If  this  fails  extension 
may  be  tried  or  tenotomy  of  the  tendo  calcaneus  should  be  done  and  the  fragments 
will  at  once  come  into  good  position. 

Woolsey  has  pointed  out  that  the  weight  of  the  foot  tends  to  its  outward  dis- 
placement but  another  reason  is  that  the  insertion  of  the  tendo  calcaneus  is  not 
beneath  the  middle  of  the  ankle-joint  but  more  towards  its  outer  side,  so  that  when 
it  contracts  it  carries  the  foot  outward.  The  flexor  and  extensor  muscles  of  the  leg 
balance  each  other,  but  the  peronei  muscles  on  the  outer  side  have  no  additional 
corresponding  opponents  on  the  inner  side;  hence  another  reason  for  displacement 
of  the  foot  and  lower  fragment  outward. 

AMPUTATION   OF  THE   LEG. 

Amputation  of  the  leg  is  best  performed  at  the  place  of  election,  a  hand's 
breadth  below  the  knee-joint.     This  site  is  preferred  because  it  gives  a  sufficient 


N 


Extensor  longus  digitorum 


Anterior  tibial  nerve 

Anterior  tibial  artery 

Peroneus  longus  and 
peroneus  brevis 

Musculocutaneous  nerve 


Peroneal  artery 


Soleus 


Gastrocnem  i  us 


Tibialis  anterior 


Interosseous  membrane 


Tibialis  posterior 
Flexor  longus  digitorum 
Flexor  longus  hallucis 


Posterior  tibial  artery 
Posterior  tibial  nerve 


Fig.  565. — Amputation  of  the  upper  third  of  the  leg. 


length  to  the  stump  below  the  knee  and  allows  sufificient  space  below  for  the  instrument 
maker  to  place  the  mechanism  of  the  artificial  leg  which  operates  the  foot.  The 
sharp  projecting  edge  of  the  crest  of  the  tibia  tends  to  produce  ulceration  of  the  tissues 
or  skin  in  front  of  it,  therefore  it  is  to  be  cut  off  obliquely. 

The  fibula,  if  divided  at  the  same  level  as  the  tibia  and  especially  if  antero- 
posterior flaps  are  used,  tends  to  project  too  prominendy  on  the  outer  side,  hence  it 
is  preferable  to  divide  it  at  a  higher  level  than  the  tibia. 

The  anterior  tibial  artery  is  to  be  sought  for  on  the  interosseous  membrane  close 
lo  the  tibia  with  its  nerve  to  the  outer  side. 

The  posterior  tibial  and  peroneal  are  at  the  same  level  on  the  tibialis  posterior 
muscle  wich  the  posterior  tibial  nerve  lying  superficial  to  the  posterior  tibial  artery 
(Fig.  565). 


REGION    OF  THE    ANKLE. 


553 


REGION  OF  THE  ANKLE. 

The  ankle-joint  is  composed  of  the  tibia  and  fibula  above  and  the  astragalus  below. 

Surface  Anatomy. — A  knowledge  of  the  contour  of  the  ankle  aids  considera- 
bly in  determining  the  character  of  its  diseases  and  injuries.  The  malleoli  form  prom- 
inences with  distinct  hollows  above  and  below  them.  The  sharp  anterior  edge  of  the 
tibia  if  followed  down  leads  to  the  tibialis  anterior  tendon.  On  the  medial  (inner)  side 
the  malleolus  is  large  and  flat.      It  is  subcutaneous  and  can  be  readily  palpated.      At 


k 


Subcutaneous  portion  of  fibula  — ^ 


External  malleolus 


Peroneal  tubercle 


External  tubercle  of  os  calcis 


Internal  cuneiform 
Middle  cuneiform 

External  cuneiform 


Tubercle  of  fifth  metatarsal 
Fig.  566. — Surface  anatomy  of  the  outer  side  of  the  ankle. 

its  anterior  edge  is  the  commencement  of  the  internal  saphenous  vein  which  runs  up 
and  slightly  back  to  reach  the  posterior  edge  of  the  tibia  5  to  6  cm.  (2  to  2  >^  in. ) 
above  the  tip  of  the  malleolus.  About  4  cm.  (i}4  in. )  below  and  in  front  of  the  inter- 
nal  malleolus  is  the  prominent  tubercle  of  the  scaphoid. 

The  external  malleolus  is  small  and  somewhat  pointed,  and  is  placed  a  finger- 
breadth  below  and  behind  the  level  of  the  internal  malleolus.  For  a  distance  of 
about  7.5  cm.  (3  in.)  above  its  tip  the  fibula  is  subcutaneous  and  readily  palpated. 
It  is  here  that  it  is  most  often  fractured.  The  transverse  line  of  the  joint  is  level  with 
the  upper  hmit  of  the  swell  of  the  internal  malleolus — about  2.5  cm.  (i  in.)  above 


Ankle-joint 


'  Internal  malleolus 


Subastragaloid  joint 
Sustentaculum  tali 


-Os  calcis 


Internal  tubercle  of  the 
OS  calcis 


Tubercle  of  the  scaphoid 
Fig.  s67. — Surface  anatomy  of  the  inner  side  of  the  ankle. 

the  tip  of  the  external  malleolus.  The  ankle  is  covered  in  front  and  behind  by  ten- 
dons, most  of  which,  especially  in  thin  people,  can  be  felt  and  seen  when  they  are 
put  on  the  stretch.  Anteriorly  the  innermost  tendon  is  the  tibialis  anterior,  next  the 
extensor  longus  hallucis,  and  then  the  extensor  longus  digitorum.  Sometimes  close 
to  the  outer  side  of  the  extensor  of  the  little  (fifth)  toe  the  contraction  of  the  pero- 
neus  tertius  tendon  can  be  felt  as  it  goes  to  be  inserted  into  the  fifth  metatarsal  bone 
near  its  base.  Running  directly  downward  along  the  posterior  edge  of  the  external 
malleolus  and  fibula  are  the  peroneus  longus  and  brevis  tendons,  the  former  being 
the  more  superficial.  About  2.5  cm.  (i  in.)  below  and  a  little  in  front  of  the  exter- 
nal malleolus  is  the  peroneal  tubercle  of  the  calcaneum;  the  peroneus  brevis  passes  in 


APPLIED    ANATOMY. 

front  of  it  to  be  inserted  into  the  prominent  tuberosity  of  the  fifth  metatarsal  bone. 
The  long  tendon  passes  behind  the  tubercle,  winds  around  the  cuboid,  and  crosses 
the  sole  to  insert  into  the  internal  cuneiform  and  base  of  the  first  metatarsal  bone. 

Posteriorly  the  tendo  calcaneus  (Achillis)  is  large  and  prominent — along  the 
anterior  edge  of  its  lateral  (external)  side  run  the  external  (short)  saphenous  vein 
and  nerve.  Running  upward  from  the  posterior  border  of  the  internal  malleolus  the 
tibialis  posterior  tendon  can  sometimes  be  seen  and  felt.  Posterior  to  it  runs  the 
flexor  longus  digitorum  muscle,  then  the  posterior  tibial  artery,  accompanied  by 
venae  comites,  then  the  posterior  tibial  nerve,  and  lastly  the  flexor  longus  hallucis. 
The  artery  can  be  felt  pulsating  midway  between  the  tendo  calcaneus  and  the 
internal  tuberosity  of  the  calcaneum.  The  anterior  tibial  artery  can  be  felt  pulsat- 
ing to  the  lateral  (outer)  side  of  the  flexor  longus  hallucis. 


THE   ANKLE-JOINT. 

Ligaments  and  Movements. — The  ankle-joint  is  a  pure  hinge-joint  and  its 
motion  is  anteroposterior  except  in  complete  extension,  when  a  small  amount  of 

lateral  movement  is  possible.  The  range  of  move- 
ment is  80  degrees;  20  degrees  flexion,  and  60  de- 
grees extension. 

The  tibia  and  fibula  above  articulate  with  the 
surface  of  the  body  of  the  astragalus  below.  The 
articular  facet  for  the  fibula  is  about  twice  as  long 
from  above  downward  as  is  that  for  the  internal 
malleolus.  The  hollow  below  the  internal  malleolus 
is  filled  by  the  internal  lateral  ligament  and  the  ten- 
don of  the  tibialis  posterior.  The  inferior  tibio- 
fibular joint  is  sometimes  practically  lacking,  there 
being  almost  no  continuation  of  the  ankle-joint  up 
between  the  tibia  and  fibula.  The  junction  of  these 
two  bones  is  very  strong,  the  ligaments  being  an 
anterior,  posterior,  interosseous,  and  a  transverse 
inferior  tibiofibular  ligament  which  passes  across  the 
back  of  the  ankle-joint  reinforcing  the  posterior  por- 
tion of  the  capsular  ligament.  The  upper  surface 
of  the  astragalus  is  one-fourth  wider  in  front  than 
behind,  so  that  in  extension  it  is  not  so  firmly  locked 
between  the  malleoli  as  in  flexion  (Fig.  568).  Its 
upper  surface  is  slightly  concave.  Flexion  and 
extension  take  place  on  a  transverse  axis  passing 
through  the  body  of  the  astragalus  at  the  tip  of  the 
external  malleolus.  This  axis  is  not  exactly  trans- 
verse but  is  slightly  oblique,  so  that  on  extension 
the  foot  is  pointed  slightly  outward.  The  ankle 
has  a  capsular  ligament  which  is  very  thin  in  front 
and  behind  the  joint.  Posteriorly  it  is  reinforced 
above  by  the  transverse  inferior  tibiofibular  liga- 
ment. The  flexor  longus  hallucis  also  supports  it 
posteriorly.  The  internal  and  external  lateral  liga- 
ments are  strong,  the  internal  being  the  stronger. 
The  internal  lateral  or  ligamentum  deltoideum 
runs  from  the  malleolus  above  to  the  scaphoid,  astragalus,  and  calcaneum  below. 
It  is  crossed  on  its  surface  by  the  tendons  of  the  tibialis  posterior  and  flexor  longus 
digitorum  muscles  (Fig.  569). 

The  external  lateral  ligament  has  three  fasciculi:  an  anterior  one  to  the  astrag- 
alus; a  middle  one  to  the  side  of  the  calcaneum,  and  a  posterior  one  to  the  posterior 
part  of  the  astragalus  (Fig.  570).  In  both  extreme  flexion  and  extension  the  edges 
of  the  tibia  come  in  contact  with  the  astragalus  and  hence  limit  further  movement. 
The  ligaments  also  aid  in  restricting  motion. 


Fig.  508. — The  upper  articular  sur- 
face of  the  astragalus,  showing  it  to  be 
slightly  concave  and  one  fourth  wider  in 
front  than  behind. 


REGION   OF   THE   ANKLE. 


555 


Distention  of  the  Joint. — Fluid  tends  to  find  exit  from  the  joint  first  ante- 
riorly under  the  extensor  tendons,  next  it  tends  to  exude  posteriorly  and  makes  its 
appearance  as  a  swelling  on  each  side  of  the  tendo  calcaneus  ( Achillis).  The  ankle- 
joint  is  a  comparatively  tight  one  and  in  acute  inflammations  holds  but  little  effusion. 
When  injected  it  assumes  the  position  of  a  right  angle  and  flexion  does  not  occur  as 


I  i 


Groove  for  flexor  longus 

hallucis^,_  ( 


Sustentaculum  tali' 


^Internal  lateral  ligament 
Anterior  tibial  tendon 


^:^ 


Posterior  tibial 
Groove  for  posterior 
tibial  tendon  on  the 
inferior  calcaneo- 
scaphoid  ligament 
Groove  for  flexor  longus  digito'rum 

Fig.   569. — View  of  inner  side  of  ankle-joint,  showing  the  internal  lateral  ligament. 

in  other  joints  (Fig.  571).  The  rounded  appearance  of  the  ankle  in  tuberculous 
and  other  affections  is  not  due  so  much  to  effusion  within  the  joint  as  to  inflam- 
matory and  tuberculous  exudate  in  the  tissues  around  the  joint. 

Tuberculosis  of  the  Ankle. — This  most  often  affects  the  body  of  the  astrag- 
alus.     Sometimes  the  disease  is  located  in  the  lower  end  of  the  tibia.      In  the  former 


Anterior  fasciculus  of  external 
lateral  ligament 

Astragalocalcaneal  ligament 


Interosseous  ligament 
Fig.  570. — Ligaments  of  the  outer  side  of  the  ankle. 


Anterior  tibiofibular 
ligament 

Posterior  (transverse)  tibio- 
fibular ligament 

Posterior  fasciculus  of 
external  lateral  ligament 
Middle  fasciculus  of 
external  lateral  ligament 


case  other  of  the  tarsal  bones  are  also  frequently  involved.  In  the  latter  an  extra- 
articular operation  on  the  tibia  above  the  internal  malleolus  may  cure  the  disease, 
but  the  motion  in  the  joint  often  remains  impaired. 

Excision  of  the  Ankle. — Formal  resections  of  the  ankle  are  rarely  performed. 
The  joint  is  difficult  to  expose  without  extensive  division  of  the  tendons  and  other 


5S6 


APPLIED    ANATOMY. 


tissues.      It  is  considered  best  to  enlarge  any  existing  sinuses  and  curette  tne 
eased  bone  away. 

If  it  is  desired  to  excise  the  joint  it  can  be  done  by  Konig's  incisions,  one  along  the 
anterior  edge  of  the  internal  malleolus  and  the  other  along  the  anterior  edge  of  the  ex- 
ternal malleolus.  Through  these  incisions  all  that  is  necessary  can  usually  be  done. 
Sprain  of  the  Ankle. — In  what  is  usually  called  a  sprain  of  the  ankle  the 
injury  is  not  always  confined  to  the  ankle-joint  and  its  ligaments.  It  has  been  shown 
that  in  many  cases  there  is  a  tearing  off  of  small  fragments  of  bone,  hence  the  name 
fracture-sprain  (Callender).  The  ankle-joint  has  an  anteroposterior  motion,  but  the 
lateral  motion  of  the  foot  takes  place  mainly  in  the  subastragaloid  joint  with  some 

additional  movement  allowed  by  the  other 
tarsal  joints.  Inasmuch  as  sprains  are 
j  usually  the  consequence  of  a  lateral  dis- 

placement, the  resultant  injury  is  frequently 
in  the  subastragaloid  and  sometimes  in  the 
adjacent  tarsal  joints.  This  condition  can 
be  suspected  when  the  pain  and  swelling 
is  located  below  and  in  front  of  the  ankle 
rather  than  around  the  ankle  itself.  The 
sprain  is  more  often  the  result  of  inversion 
than  of  eversion  of  the  foot.  In  eversion 
the  plantar  ligaments  are  so  strong  that  the 
foot  moves  as  a  whole  and  the  force  is  trans- 
mitted directly  to  the  ankle  and  leg  bones, 
and  most  likely  results  in  the  production  of 
a  Pott's  fracture  of  the  fibula  with  or  with- 
out a  tearing  off  of  the  internal  malleolus 
V  _^  ^'^  rupture  of  the  ligamentum  deltoideum 

^P^T^.,,      _       V  .y  _.^---.-  (internal  lateral). 

-^^^"        '^^  *" '^^^^^^'^j^  Treatment. — The    principle  of   treat- 

ment in  sprains  is  to  prevent  the  ruptured 
ligaments  and  strained  tissues  being  again 
irritated  and  kept  from  healing  by  subse- 
quent movements  of  the  injured  parts. 
A  small  degree  of  movement  is  usually 
painless  and  unharmful,  but  a  more  extensive,  and  often  accidental,  movement  causes 
the  pain  and  disability  to  persist.  The  failure  to  apply  an  efificient  dressing  which 
properly  limits  motion  until  the  primary  effect  of  the  injury  has  passed  is  the  reason 
of  these  disabilities  becoming  chronic.  Sometimes  fixed  dressings  like  plaster  of 
Paris  or  silicate  of  soda  are  applied  for  two  weeks.  Fixation  by  adhesive  plaster  has 
been  found  very  efificient.  Gibney  demonstrated  this.  Inasmuch  as  the  injury  is 
usually  produced  by  inversion,  the  plaster  is  applied  especially  to  prevent  inversion 
and  likewise  to  give  general  support.  Gibney' s  method  consisted  in  applying  alter- 
nate narrow  strips  of  adhesive  plaster,  one  set  beginning  on  the  inner  side  of  the  foot 
and  going  well  up  on  the  outer  side  of  the  leg,  and  the  other  running  parallel  with 
the  sole  of  the  foot  from  the  heel  to  the  dorsum. 

Another  method  consists  in  taking  a  long  strip  of  plaster  7.5  cm.  (3  in.)  wide, 
and  beginning  high  up  the  leg  on  the  inner  side,  carrying  it  down  under  the  sole 
and  drawing  it  firmly  up  and  fastening  on  the  outer  side  of  the  leg  almost  to  the 
knee.     This  is  reinforced  by  encircling  strips  around  the  ankle  and  instep. 


Fig.  571. — Ankle-joint  distended  with  wax,  show- 
ing that  its  capsule  is  weak  anteriorly  and  posteriorly 
and  strong  laterally. 


DISLOCATIONS   OF   THE   ANKLE. 

The  foot  may  be  dislocated  from  the  leg  in  nine  different  manners. 

1.  The  foot  as  a  whole  may  be  carried  outward.  This  is  almost  always  asso- 
ciated with  fracture  of  the  fibula,  and  sometimes  of  the  internal  malleolus,  constituting 
Pott's  fracture  (see  page  557). 

2.  The  foot  may  be  carried  direcdy  inward.  This  likewise  is  associated  with 
fracture  of  the  internal  malleolus. 


REGION   OF   THE  ANKLE. 


557 


3.  The  foot  may  be  rotated  out  on  its  own  anteroposterior  horizontal  axis  (paral- 
lel with  the  sole). 

4.  It  may  be  rotated  in  on  its  anteroposterior  horizontal  axis.      Both  these  may 
be  accompanied  by  fractures. 

5.  The  foot  may  be  rotated  inward  on  a  vertical  axis  longitudinally  through 
the  leg. 

6.  It  may  be  rotated  outward  on  a  vertical  axis. 

7.  The   foot    may   be   luxated    backward,    the    tibia    coming   forward    on    the 
astragalus  (Fig.  572). 

8.  It  may  be  luxated  forward. 

9.  The  astragalus  may  be  pushed  up  between  the  bones  of  the  leg. 

In  Numbers  i  and  2  inward  and  outward  displacement  the  foot  is  not  immedi- 
ately beneath  the  leg,   but  is  to  one  side  of  the  leg.     The  outward  luxation  when 
accompanied  with  laceration  of  the  inferior  tibiofibular  ligaments  or  tearing  off  of  a 
small   portion  of  the  tibia  and  fracture  of  the 
internal  malleolus  and  fibula  constitutes  Dupuy- 
tren's  or  Pott's  fracture.      In  Numbers  3  and  4 
the  foot  remains  beneath  the  leg  bones  and  is 
not  displaced  much  laterally.    Numbers  i  and  3  | 

are  usually  grouped  together  as  outward  luxa-  I  \ 

tions,  and  2  and  4  as  inward  luxations.     Num-  ' 

bers  5  and  6  are  very  rare.  The  foot  is  rotated 
so  that  one  side  looks  forward  and  the  other 
backward. 

jN'umber  7  backward  luxation  is  the  most 
common,  with  the  exception  of  Number  i. 
When  associated  with  Pott's  fracture,  backward 
luxation  is  produced  by  hyperextension  followed 
by  a  thrust  and  is  often  compound.  The  leg  is 
bent  backward  until  the  anterior  and  lateral  lig- 
aments rupture,  and  then  the  thrust  sends  the 
tibia  forward  on  the  instep.  The  articular  sur- 
face of  the  astragalus  being  wider  in  front  op- 
poses the  luxation,  and  fracture  of  one  or  both 
malleoli  may  result. 

Numbers  8  and  9  forward  and  upward  lux- 
ations are  extremely  rare,  the  former  on  account 
of  the  difficulty  in  the  application  of  the  dislo- 
cating force, — the  flexion  and  thrust, — and  the 
latter  on  account  of  the  extreme  strength  of  the 
inferior  tibiofibular  ligaments. 

Treabneyit.  —  In  attempting  reduction  of 
these  luxations  the  principal  thing  is  to  relax  the  tendo  calcaneus  (Achillis)  by  flexing 
the  knee.  If  this  is  not  sufficient,  tenotomy  should  be  practiced.  Simple  extension 
with  slight  rotation  and  manipulation  will  then  accomplish  reposition. 


Fig.   572. — Backward  lujcation  of  the  foot  at 
the  ankle-joint. 


FRACTURES   OF  THE  ANKLE. 

Fractures  of  the  ankle  are  usually  the  result  of  a  force  applied  laterally,  though 
sometimes  a  turning  of  the  foot  on  the  vertical  axis  of  the  leg  may  assist.  The  force 
applied  causes  fracture  by  inversion  or  eversion  of  the  foot. 

Pott's  Fracture  or  Fracture  by  Eversion. — This  is  named  after  Sir  Perci- 
val  Pott,  Surgeon  to  St.  Bartholomew's  Hospital,  London,  who  described  the  injury, 
and  was  himself  a  victim  of  it.  The  French  call  it  Dupuytren's  fracture.  It  is  pro- 
duced by  forcing  the  foot  outward,  or  by  having  the  foot  firmly  fixed  and  then 
bending  the  Hmb  outward,  thus  breaking  it  at  the  ankle.  The  fibula  is  broken  4  to 
7.5  cm.  (i^  to  3  in. )  above  its  lower  end  and  the  ligamentum  deltoideum  (internal 
lateral)  is  either  ruptured  or  the  internal  malleolus  is  torn  of^.  Rarely  the  outer 
portion  of  the  articular  surface  of  the  tibia  may  be  torn  of?  and  displaced  outward 


558 


APPLIED    ANATOMY. 


with  the  lower  fibular  fragment.  It  is  to  be  noted  that  in  this  fracture  the  foot,  with 
the  small  fragments  of  tibia  and  fibula,  is  practically  loosened  from  the  bones  of  the 
leg,  and  the  muscles  of  the  calf  being  unopposed  pull  the  foot  backward  and  upward. 
Therefore  the  displacement  of  the  foot  is  not  only  outward,  but  also  backward  and 
upward  (Fig.  573.) 

Fracture  by  Inversion. — This  is  practically  the  opposite  of  the  former  and  is 
not  so  frequent.  The  fibula  is  fractured  by  the  traction  of  the  external  lateral  liga- 
ments which  remain  intact;  it  may  break  either  above  or  below  the  strong  inferior 
tibiofibular  ligaments.  The  internal  malleolus  may  also  be  torn  off.  The  displace- 
ment is  toward  the  inner  side  and  upward  and  backward  (Fig.  574). 

Treatment.  —  In  these  fractures  of  the  ankle  replacement  is  often  difficult  and 
resultant  deformities  frequently  cause  considerable  subsequent  disability.      For  this 

reason  especial  efforts  are  to  be  made  to  reduce 
the  displacement  and  maintain  the  fragments  in 
proper  position. 

There  are  two  main  points  of  difficulty.    The 

fractured  ends  of  the  fibula  become  displaced  an- 

.  I  teroposteriorly  and  also  in  the  fracture  by  ev^er- 

/ :  sion  (Pott's)  become  pushed  inward  toward  the 


Fig.  5  73. — Pott's  fracture  of  tlie  fibula,  showing  eversion  of  the 
foot,  point  of  fracture  of  the  fibula,  and  tearing  off  of  the  point  of  the 
internal  malleolus. 


Fig.    574. — Illustrating  fracture  of  the 
fibula  by  inversion  of  the  foot. 


tibia.  The  deep  fascia  of  the  leg  is  attached  to  the  fibula  and  its  sharp  broken  ends 
may  get  so  fastened  or  caught  in  this  fascia  as  to  require  an  op^n  incision  before 
they  can  be  freed  sufficiently  to  allow  of  their  proper  replacement.  Another  difficulty 
is  in  the  reduction  of  both  the  lateral  and  posterior  displacement.  Here  it  is  neces- 
sary first  to  relax  the  muscles  of  the  calf  by  flexing  the  leg  on  the  thigh,  then  by 
pulling  and  direct  pressure  the  foot  can  often  be  replaced.  If  this  fails  tenotomy  of 
the  tendo  calcaneus  (Achillis)  is  to  be  done,  which  relaxes  the  parts  still  more  by 
leleasing  the  pull  of  the  soleus,  the  gastrocnemius  and  plantaris  being  already  re- 
laxed by  flexion  of  the  knee.     This  is  sometimes  necessary  to  prevent  the  persistent 


REGION   OF   THE   ANKLE. 


559 


tendency  of  the  foot  to  be  drawn  backward.  After  reduction  not  infrequently  there  is 
no  further  tendency  to  displacement,  and  the  fracture  box  or  any  other  simple  means 
of  retention  is  sufficient. 

In  other  cases  it  is  better  to  place  the  leg  in  the  Pott's  position,  viz.,  lying  on 
its  outer  side  with  the  knee  flexed.  For  similar  injuries,  Dupuytren  advised  placing 
the  leg  on  a  straight  internal  lateral  splint  on  a  pad  which  extended  from  near  the 
knee  down  to  the  seat  of  fracture.  The  leg  was  fastened  near  the  knee  to  the  upper 
part  of  the  splint,  and  the  foot  which  projected  beyond  the  pad  was  drawn  by 
bandages  toward  the  lower  part  of  the  splint. 

AMPUTATIONS   AT   THE   ANKLE. 

When  amputation  is  performed  at  the  ankle  it  is  usually  either  by  the  method 
of  Syme  or  that  of  Pirogoff. 

Syme's  Amputation. — "A  transverse  incision  should  be  carried  across  the 
sole  of  the  foot  from  the  tip  of  the  external  malleolus  or  a  little  posterior  to  it  (rather 


Extensor  longus  hallucis 

Tibialis  anterior"" 
Anterior  tibial  artery 


Tibia— f- 


Tibialis  posterior 
Flexor  longus  digitorum 

Plantar  arteries  and  nerves 


Extensor  longus  digitorum 


Fibula 


Peroneus  longus 
Peroneus  brevis 

Flexor  longus  hallucis 


Pocket  left  by  enucleating 
the  OS  calcis 


Flu.  575. — Syme's  amputation  of  the  ankle. 


nearer  the  posterior  than  the  anterior  edge  of  the  bone)  to  the  opposite  point  on  the 
inner  side,  which  will  be  rather  below  the  tip  of  the  internal  malleolus."  The  extrem- 
ities of  this  incision  are  connected  by  another  directly  across  the  front  of  the  ankle- 
joint.  The  anterior  capsule  is  then  divided  and  the  lateral  ligaments  divided  from 
within  outward.  The  foot  being  bent  down,  the  tendo  calcaneus  is  cut  close  to  the 
bone  and  the  calcaneum  dissected  out.  The  malleoli  are  then  to  be  cleared  and  sawn 
off  with  a  thin  slip  of  the  articular  surface  of  the  tibia  (Fig.  575). 

Remarks:    The  incision    across  the   sole    must    not   go    too  far  back  on  the 
inner  side,   as    the  internal    calcanean    branch    of   the  external    plantar   artery  will 


56o 


APPLIED    ANATOMY. 


be  divided  and  the  integrity  of  the  flap  threatened.  In  clearing  the  calcaneum  it  is 
rather  an  advantage,  especially  in  young  people,  to  take  off  a  thin  slice  of  bone  with 
the  tendo  calcaneus.  In  removing  the  slice  from  the  tibia  as  little  as  possible  (in 
growing  patients)  should  be  removed,  to  avoid  injuring  the  epiphyseal  cartilage. 
In  dissecting  back  the  flap  of  the  heel,  the  point  of  the  knife  is  to  be  kept  close  to 
the  bone  to  avoid  cutting  the  vessels  in  the  flap  itself. 

Pirogoff's  Amputation. — The  sole  incision  is  carried  across  from  just  in  front 
of  the  external  malleolus  to  just  in  front  of  the  internal.  The  anterior  incision  is 
made  across  the  front  of  the  joint  and  the  foot  disarticulated  by  dividing  the  cap- 
sular and  lateral  ligaments.      The  foot  is  then  bent  down  and  the  calcaneum  sawn 


Extensor  longus  digitorum 


Fibula  _. 


Peroneus  longus 


Peroneus  brevis 


Sawn  surface  of  os  calcis 


Extensor  longus  hallucis 
Tibialis  anterior 


Tibia 

Tibialis  posterior 
Flexor  longus  digitorum 
Flexor  longus  hallucis 

Plantar  vessels  and  nerves 


Fig.  576. — Pirogoff's  amputation  of  the  ankle. 


through  the  line  of  the  sole  incision.  A  slice  is  to  be  removed  from  the  tibia  and 
fibula  and  the  sawn  surface  of  the  calcaneum  brought  up  and  sutured  with  chromic 
catgut  (or  other)  sutures  to  the  sawn  surface  of  the  tibia  (Fig.  576). 

In  bringing  up  the  calcaneum  to  the  tibia  it  may  be  found  difficult  to  approxi- 
mate them  without  undue  tension  on  the  tendo  Achillis.  To  provide  against  this 
common  difficulty  it  is  customary  to  place  the  saw  on  the  upper  surface  of  the  calca- 
neum well  behind  (a  finger-breadth)  the  joint.  Also  to  dissect  back  the  heel-flap 
.50  to  I  cm.  (^  to  ^  in.)  so  that  more  of  the  calcaneum  can  be  removed.  A 
larger  slice  is  also  taken  from  the  tibia  than  in  Syme's  amputation.  If  the  tension 
remains  too  great  on  the  tendo  calcaneus  it  is  to  be  divided. 


THE  FOOT. 


S6i 


THE  FOOT. 

The  foot  is  intended  for  support  and  locomotion.  The  locomotion  takes  place  in 
the  upright  position  and,  in  moving,  the  weight  is  shifted  from  one  foot  to  the  other. 
Hence  we  see  that  if  the  foot  is  to  fulfil  its  function  of  support  it  must  have  strength, 
because  on  it  rests  the  weight  of  almost  the  whole  of  the  body.  If  a  person  is  at  rest 
in  a  standing  position  the  foot  is  subject  to  a  continuous  static  pressure  which,  if  any 
part  of  the  foot  is  abnormal,  whether  from  congenital  or  acquired  qualities,  will  event- 
ually result  in  distortion  and  impairment  of  function.  If  a  person  is  moving  about, 
the  foot  is  subjected  to  a  pressure  which  is  dynamic  (movable)  in  character,  and  is 
much  greater  in  amount  than  is  the  static  pressure  of  the  body  at  rest. 

The  movements  of  the  foot  in  locomotion  are  not  always  slow,  sometimes  they 
are  exceedingly  rapid.  A  person  treads  on  an  uneven  or  unstable  surface  and  the 
foot  must  adapt  itself  instantly  or  injuries  will  result;  failure  to  do  so  results  in  sprains, 
fractures,  and  luxations.  In  running  rapidly  the  changes  in  position  of  the  com- 
ponent parts  of  the  foot  are  instantaneous,  otherwise  rapid  running  is  impossible.  In 
jumping  especially  the  dynamic  pressure  plus  the  inertia  causes  an  enormous  strain 
on  the  foot.  The  mobility  demanded  of  the  foot  is  not  so  great,  however,  as  that  of 
the  hand  because  the  movements  are  neither  so  intricate  nor  so  numerous.  A  con- 
sideration of  these  facts  enables  one  to  understand:  first,  the  method  of  construction 
of  the  foot;  second,  its  injuries,  diseases  and  deformities;  third,  the  means  necessary 
to  employ  m  preventing  and  curing 
them  and  m  obviating  to  as  great 
extent  as  possible  their  consequences. 

The  Construction  of  the 
Foot. — The  foot  is  constructed  with 
a  view  of  possessing  strength  and 
mobility.  Strength  is  obtained  by 
the  bones  being  short  and  solid,  well 
compacted  together  in  the  form  of  a 
double  arch,  joined  by  strong  liga- 
ments, and  supported  by  powerful 
muscles.  The  double  arch  forms  the 
hollow  of  the  sole  of  the  foot.  As 
pointed  out  by  Ellis  ( ' '  The  Human 
Foot ' '  )  when  the  two  feet  are  placed 
together  there  is  formed  a  "  dome-shaped  space  "  arching  anteroposteriorly  from  the 
internal  tuberosity  of  the  calcaneum  to  the  head  of  the  first  metatarsal  bone,  and 
laterally  from  the  inner  to  the  outer  edge  (Fig.  577).  Mobility  is  obtained  by  the 
bones  and  joints  being  numerous  and  the  muscles  highly  specialized. 

Diseases  and  Injuries  of  the  Foot. — Disease  weakens  the  foot — sometimes, 
as  in  adolescents,  the  foot  is  weakened  without  any  apparent  disease.  In  other  cases 
the  bones  and  ligaments  become  affected,  as  in  rickets,  rheumatism,  gout,  and  tuber- 
culous disease.  In  still  other^;  the  muscles  become  affected,  either  contracted,  as  in 
spastic  diseases,  or  relaxed,  as  in  infantile  paralysis.  When  the  bones  and  ligaments 
are  involved  they  fail  to  bear  the  body  weight,  the  arch  is  crushed  and  flat-foot  and 
eversion  results.  Hence  valgus  is  almost  always  a  disease  of  weakness.  If  muscles 
become  affected  by  spasm  or  paralysis  all  kinds  of  deformities  are  produced.  There 
are  many  muscles  controlling  the  foot  and  frequently  only  one  or  a  few  are  paralyzed ;. 
this  leaves  the  balancing  muscles  unopposed  and  they  drag  the  part  toward  the 
healthy  side.  Anything  that  disturbs  the  equilibrium  or  balance  of  the  various 
muscles  results  in  distortions  and  deformities.  Injuries  impair  the  efficacy  of  the 
mechanism  of  the  foot.  A  crush  of  the  head  of  the  first  metacarpal  bone  destroys 
the  anterior  support  of  the  arch  and  the  resultant  weakness  is  marked. 

Traumatism  produces  flat-foot,  also  sprains,  which,  while  not  so  deforming,  are 
often  disabling.     Fractures  and  luxations  occur  and  may  impair  the  foot  permanently. 

Finally,  many  children  have  congenitally  deformed  feet  which  require  treatment 
before  they  can  fulfil  their  functions. 
36 


Inferior  calcaneo-scaphoid  ligament. 
Fig.  577. — Section  of  toot,  showing  the  longitudinal  arch. 


5< 


APPLIED    ANATOMY. 


The  Treatment  of  Affections  of  the  Feet. — The  foot  is  exceptionally 
accessible  both  for  diagnosis  and  treatment.  The  bones  and  joints  are  accessible 
often  to  both  sight  and  touch,  and  one  should  know  where  to  look  and  feel  for  them. 
Exploratory  operations  in  this  portion  of  the  body  are  out  of  place.  An  accurate 
knowledge  of  the  structures  of  the  foot  is  absolutely  essential  to  intelligent  treatment. 
The  deformities  are  dependent  on  muscular  action,  and  one  should  know  the  position 
of  the  tendons  and  the  influence  of  the  muscles.  In  amputating,  a  knowledge  of  the 
joints  is  essential.  The  problems  presented  are  largely  of  a  mechanical  nature,  to  be 
solved  by  a  thorough  knowledge  of  the  structures  and  the  application  of  mechanical 
principles  to  living  tissues. 


Astragalus 


Os  calcis 


Cuboid 


Tuberosity  of 
/  ~^      fifth  metatarsal 


BONES    OF   THE   FOOT. 

A  knowledge  of  the  bony  structure  of  the  foot  is  the  key  which  unlocks  its 
pathology.      The  bones  of  the  foot  are  numerous,  so  as  to  give  it  mobility  and  to 

lessen  shocks.    If  the  bones  become 
/""^  ankylosed  the  footing  becomes  in- 

secure, balancing  is  difficult,  the 
gait  is  altered,  and  great  care  is 
necessary  in  locomotion  to  avoid 
straining  and  injury. 

The  foot  is  triangular  in  shape, 
being  broad  across  the  toes  and 
narrow  at  the  heel.  Its  bones  com- 
pose the  tarsals,  metatarsus,  and 
phalanges.  Of  these  the  first  two 
are  essential,  but  the  third  is  less 
so.  Phalanges  are  more  or  less 
for  prehensile  uses,  and  as  man,  as 
we  see  him,  encases  his  foot  in 
shoes  he  makes  but  little  use  of  the 
toes,  hence  they  are  the  least  im- 
portant part  of  the  foot.  They  are 
used  somewhat  in  walking,  and  to  a 
greater  degree  in  balancing,  climb- 
ing, running,  etc.  They  add  to  the 
efficiency  of  the  foot,  but  their  loss 
does  not  impair  it  to  a  great  extent. 
Intricate  and  delicate  movements 
may  be  interfered  with,  but  the 
more  deliberate  firmer  movements, 
as  in  walking,  may  remain  almost 
normal.  The  big  toe  has  only  two 
phalanges  and  this  increases  its 
strength  at  the  cost  of  mobility. 
The  remaining  portion  of  the  foot 
is  composed  of  the  metatarsus  and 
tarsus — five  bones  of  the  former 
and  seven  of  the  latter. 

The  foot  bones  are  divided 
longitudinally  into  two  sets,  an  in- 
ternal and  external.  The  main 
weight  of  the  body  is  transmitted  through  the  internal  set,  which  is  in  relation  with  the 
tibia.  It  consists  of  the  astragalus  {talus),  scaphoid  {navicular) ,  the  three  czineiform, 
and  the  inner  three  metatarsal  bones  with  their  corresponding  phalanges  (Fig.  578). 
The  external  set  is  in  relation  with  the  fibula,  and  is  composed  of  the  os  ccilcis, 
cuboid,  and  outer  two  metatarsals  with  their  corresponding  phalanges. 

As  has  been  pointed  out  by  Quenu  and  Kuss  {Revue  de  Chirurgie,  Jan.,  1909, 
p.  i),  while  the  main  function  of  the  internal  portion  of  the  foot  is  support,  that  of 


Fig. 


578. — Anterior  view  of  the   bones  of  the  foot  showing 
their  division  into  internal  and  external  sets. 


THE  FOOT. 


563 


the  external  portion  is  balance.  They  suggest  that  from  a  functional  standpoint  the 
foot  may  be  divided  into  an  internal  portion  composed  of  all  the  tarsal  bones  and 
the  first  metatarsal  bone  with  its  phalanges,  and  an  external  portion  consisting  of 
the  outer  four  metatarsal  bones  and 

Astragalus 

External,  middle,  and  internal 

cuneiform  bones 


Metatarsal 


Os  calcis 

Inferior  calcaneo- 

scaphoid  ligament 


Scaphoid  (tubercle) 
:g. — The  inner  arch  of  the  foot. 


phalanges.  They  show  that  in  dis- 
location of  the  metatarsus  the  line 
of  division  passes  between  the  first 
and  second  metatarsal  bones;  the 
first  metatarsal  is  usually  displaced 
inwardly,  while  the  second,  third, 
fourth,  and  fifth  metatarsal  bones 

are    practicall)'    always    displaced        os  caicis     /       \     Highest  point  of  arch 
outwardly,   there  being  a  consid- 
erable separation  between  the  met- 
atarsal bone  of  the  big  toe  and  the  fig. 
second  metatarsal   bone  adjacent. 

When  there  is  congenital  absence  of  the  tibia  the  foot  bones  related  to  it  are 
also  lacking,  and  when  the  fibula  is  lacking  there  are  no  bones  of  the  external  set. 
In  man  both  sets  contribute  to  support,  but  the  tibial  or  inner  set  is  the  more  impor- 
tant, the  fibular  or  outer 
Os  calcis  set  being  in  a  condition 
of  regression. 

As  has  been  stated 
above,  the  foot  is  dome- 
shaped,  being  arched 
anteroposteriorly  and 
transversely.  The  an- 
teroposterior arching 
has  been  divided  into 
an  inner  and  outer  arch. 
The  inner  arch  is  com- 
posed of  the  OS  calcis, 
astragalus,  scaphoid, 
three  cuneiform  and  inner  three  metatarsal  bones.  The  highest  point  of  this  arch  is  the 
midtarsal  joint  between  the  astragalus  and  scaphoid  (Fig.  579).  The  outer  arch  is 
composed  of  the  os  calcis,  cuboid,  and  outer  two  metatarsal  bones.  It  is  much  lower 
than  the  inner  arch.  The  highest  point 
is  between  the  cuboid  and  os  calcis,  and 
when  weight  is  borne  on  the  foot  this  outer 
arch  becomes  obliterated  and  comes  in  con- 
tact with  the  ground. 

The  transverse  arch  has  its  outer  end 
supported  by  the  outer  edge  of  the  foot, 
which  through  the  medium  of  the  soft  parts 
is  in  contact  with  the  ground.  Its  inner  end 
is  supported  by  the  inner  edge  of  the  foot 
which  is  some  distance  above  the  ground. 
Thus  it  is  seen  that  the  weight  of  the 
body  is  transmitted  from  the  body  of  the 
astragalus  in  three  directions,  viz. ,  back- 
ward to  the  tuberosities  of  the  os  calcis,  for- 
ward to  the  heads  of  the  metatarsal  bones, 
and  laterally  toward  the  base  of  the  fifth 
metatarsal  bone.  The  posterior  pillar  of  the  anteroposterior  arch  is  short,  thick,  and 
composed  of  only  two  bones,  the  astragalus  and  os  calcis.  It  is  stifl  and  strong,  but 
having  only  two  parts  is  comparatively  immovable.  The  anterior  pillar  of  the  arch 
is  longer  and  has  more  bones  and,  while  it  is  not  so  strong  against  static  pressure  as 
the  posterior  pillar,  is,  on  account  of  its  elasticity  and  mobility,  far  more  eflfective 
against  dynamic  (active)  pressure.     Thus  it  is  that  when  a  person  jumps  from  a 


Fourth  Fifth      Cuboid 

metatarsal   metatarsal 

Fig.  580. — The  outer  arch  of  the  foot. 


581. — Transverse  arch  of  foot. 


APPLIED   anatomy: 

height  and  aHghts  on  the  sole  of  the  foot  the  astragalus  or  os  calcis  of  the  posterior 
pillar  is  fractured  while  the  bones  of  the  anterior  pillar  escape.  The  internal  part 
of  the  foot  is  more  liable  to  give  way  than  the  external  part  because  the  external  part  is 
practically  in  contact  with  the  ground  while  the  internal  part  has  as  its  support  ligaments 
and  muscles,  and  when  these  latter  give  way  it  is  the  inner  side  of  the  foot  which  sinks. 
This  is  still  more  favored  by  the  position  of  the  tuberosities  of  the  os  calcis  with  refer- 
ence to  the  ankle-joint;  they  are  not  directly  beneath  it,  but  somewhat  to  its  outer  side. 


THE  JOINTS   AND   LIGAMENTS   OF   THE   FOOT. 

The  amount  of  movement  that  takes  place  between  the  bones  of  the  foot  is  not 
as  great  as  would  be  expected  from  their  number.  It  is  only  in  the  subastragaloid 
joint  that  any  considerable  motion  takes  place,  while  a  less  amount  occurs  at  the 


Tendo  calcaneus  (AchilHs). 


Peroneus  longus  and  brevis 


Posterior  articular  surface 
on  OS  calcis 


Anterior  articular  surface 
on  OS  calcis 


Plantar  vessels  and  nerves 

Flexor  longus  hallucis 

Flexor  longus  digitorum 

Interosseous  astragalo- 
calcaneal  ligament 

Inferior  calcaneo-scaphoid 

ligament 

Posterior  tibial  tendon 
Scaphoid 

Anterior  tibial  tendon 

Extensor  longus  hallucis 
Anterior  tibial  vessels 


I 


Fio.  582. — The  subastragaloid  joint;  lower  surface.     The  astragalus  has  been  removed. 

midtarsal  joint.  The  contiguous  tarsal  bones  are  joined  by  numerous  band-like, 
capsular,  and  interosseous  ligaments  which  allow  a  limited  amount  of  movement 
between  them.  In  the  aggregate  these  movements  are  considerable  and  make  the 
foot  as  a  whole  quite  flexible. 

The  Subastragaloid  Joint  (Articulatio  talo-calcaneo-navicularis). — This 
is  a  horizontal  joint  formed  by  the  astragalus  above  and  the  os  calcis  and  navicular 
(scaphoid)  below  and  in  front.  It  runs  obliquely  forward  and  inward.  The  astrag- 
alus is  not  wedged  in  between  the  os  calcis  and  scaphoid  like  the  keystone  of  an 
arch,  but  the  foot  moves  freely  beneath  it.  It  has  an  inward  motion  of  adduction 
around  an  anteroposterior  or  longitudinal  axis  with  internal  rotation  around  a  vertical 
axis,  and  an  outward  motion  of  abduction  with  external  rotation.  The  abduction 
and  adduction  movements  cannot  occur  independently  of  rotation,  they  are  com- 
bined.    The  astragalus  is  joined  to  the  os  calcis  below  and  scaphoid  below  and  in 


THE  FOOT. 


565 


front  by  short  fibrous  bands  which  help  to  form  the  capsule.  The  under  surface  of  the  sub- 
astragaloid  joint  is  formed  first  by  the  surface  of  the  scaphoid,  next  by  the  inferior  calca- 
neoscaphoid  ligament,  then  by  the  upper  surface  of  the  sustentaculum  tali,  then  by  the 
interosseous  ligament,  and  finally  by  the  posterior  surface  of  the  os  calcis.  The  infe- 
rior calcaneoscaphoid  ligament  is  the  most  important  one  in  maintaining  the  integrity  of 


Groove  for  flexor  longus 
ballucis 


Sustentaculum  tal 


Posterior  tibia]  tendon 
Groove  for  posterior 
tibial  tendon  on  the 
inferior  calcaneo- 
scaphoid ligament 
Groove  for  fiexor  longus  digitorum 


Fig.  583. — View  of  inner  side  of  ankle-joint,  showing  the  internal  lateral  ligament. 

the  arch  (Fig.  582).     In  addition,  in  order  to  provide  against  luxation,  which  is  favored 
by  the  superincumbent  body  weight,  the  joint  is  strengthened  by  three  ligaments,  viz. : 

1.  The  interosseous  astragalo-calcaneal  ligament,  which  runs  obliquely  forward 
and  outward  between  the  os  calcis  and  astragalus  and  divides  the  subastragaloid  joint 
into  an  anterior  and  posterior  portion.     It  is  very  strong  (Fig.  582). 

2.  The  internal  lateral  (^deltoid)  ligatnent  of  the  ankle,  which  sends  fibres  by- 


Anterior  fasciculus  of  external 
lateral  ligament 

Astragalocalcaneal  ligament 


Anterior  tibiofibular 
ligament 

Posterior  (transverse)  tibio- 
fibular ligament 

Posterior  fasciculus  of 
•external  lateral  ligament 
Middle  fasciculus  of 
xtemal  lateral  ligament 

A 


Interosseous  ligament 
Fig.  584. — Ligaments  of  the  outer  side  of  the  ankle. 


its  deep  part  from  the  tibia  above  to  the  side  of  the  astragalus  below  and  likewise  to 
the  scaphoid  in  front,  and  by  its  superficial  part  to  the  sustentaculum  tali  (Fig.  583). 
3.  The  external  lateral  ligameyit  of  the  ankle,  the  anterior  and  posterior  fascic- 
uli of  which  are  both  attached  to  the  astragalus  and  the  middle  fasciculus  of  which 
goes  to  the  os  calcis  below  (Fig.  584). 


566 


APPLIED    ANATOMY. 


When  the  weight  of  the  body  is  transmitted  to  the  foot  it  tends  to  flatten  the 
anteroposterior  arch.  If  the  arch  descends  it  can  only  do  so  either  by  pushing 
the  astragalus  up — luxating  it — or  by  the  ligaments  of  the  arch  stretching  or  ruptur- 
ing and  allowing  the  two  pillars  of  the  arch  to  separate.  In  disease  the  ligaments 
elongate  and  by  violence  they  may  be  ruptured,  the  arch  in  each  case  falls.  If 
the  ligaments  supporting  the  astragalus  remain  intact  then  excessive  lateral  move- 
ment ruptures  those  on  the  side  and  a  sprain  of  the  subastragaloid  joint  is  produced 
which  is  often  called  a  sprain  of  the  ankle. 

The  Midtarsal  Joint  (Chopart's  Joint)!^ — This  is  composed  anteriorly  of 
the  scaphoid  and  cuboid  bones  and  posteriorly  by  the  astragalus  and  os  calcis.  The 
movements  are  not  extensive  and  consist  of  flexion  with  inward  rotation  of  the  sole, 
and  extension  with  outward  rotation  of  the  sole.  The  joint  is  separated  into  an  inner 
and  outer  portion  by  an  interosseous  ligament  where  the  cuboid,  astragalus,  and  os 
calcis  meet. 

The  Ligamentous  Support  of  the  Arch  of  the  Foot.— The  bony  con- 
struction of  the  arch  or  dome  of  the  foot  has  already  been  explained  (page  563).  The 


Long  plantar  ligament 

Short  plantar  ligament 

Peroneus  longus 
Peroneus  brevis 


Groove  for  flexor  longus  hallucis 


Groove  for  posterior  tibial  and  flexor 
communis  digitorum 


Inferior  calcaneoscaphoid  ligament 
Posterior  tibial  tendon 


Fig.  585. — Ligaments  and  tendons  of  the  sole  of  the  foot. 


various  bones  composing  it  are  bound  together  not  only  by  the  short  ligaments  pass- 
ing between  contiguous  bones,  but  the  arch  is  strengthened  by  three  special  ligamen- 
tous structures.  They  are  the  inferior  calcaneoscaphoid  ligament,  the  plantar  liga- 
ments, long  and  short,  and  the  plantar  fascia. 

The  inferior  calcaneoscaphoid  ligament  {Jigamentum  calcaneonaviciclare pianiare) 
runs  from  the  lower  inner  portion  of  the  scaphoid,  posterior  to  its  tubercle,  to  the  sus- 
tentaculum tali.  It  is  an  extremely  strong  fibrocartilaginous  band.  Anteriorly  and 
above  it  blends  with  the  internal  lateral  ligament  (deltoid)  of  the  ankle.  Together 
with  the  posterior  surface  of  the  scaphoid  it  forms  a  socket  for  the  head  of  the 
astragalus.  This  ligament  fills  the  long  gap  left  in  the  inner  arch  of  the  foot  between 
the  scaphoid  and  os  calcis.  Running  under  and  supporting  it  is  the  tendon  of  the 
tibialis  posterior  (Fig.  585). 

The  long  plantar  or  long  calcaneocuboid  ligament  {ligametitum  plantare 
longuni)  is  attached  to  the  under  surface  of  the  os  calcis  in  front  of  its  tubercles 
and  thence  runs  to  the  peroneal  ridge  on  the  cuboid  bone  and  continues  onward  to 


THE  FOOT. 


567 


the  bases  of  the  second,  third,  fourth,  and  fifth  metatarsal  bones.     It  makes  a  canal 
for  the  peroneus  longus  tendon,  which  runs  beneath  it. 

The  short  playitar  or  short  calcaneocuboid  }igamc7it  {^ligame^itiim  calcaneo- 
cuboidcuni  plantare)  lies  beneath  the  long  ligament  and  is  separated  from  it  by  a 
small  amount  of  fatty  tissue.  It  runs  obliquely  forward  and  inward  from  the  under 
surface  of  the  calcaneum  to  the  posterior  portion  of  the  cuboid. 

The  Plantar  Fascia  (aponeurosis  plantaris). — The  middle  portion  of  the  plantar 
fascia  runs  anteriorly  from  the  inner  tubercle  of  the  os  calcis  to  be  attached  to  the 
sides  of  the  metatarsophalangeal  articulations  and  bases  of  the  proximal  phalanges. 


Outer  iMjrtion  of  plantar  fascia 


Plantar  arteries  and  nerves 


Digital  arteries  and  nerves 


Middle  portion  of  plantar  fascia 


/^  ■ —    Inner  portion  of  plantar  fascia 


Digital  arteries  and  nerves 


Fig.  580. — The  plantar  fascia. 

It  is  a  thick,  strong  triangular  band.  The  outer  portion  is  a  strong  band  running 
from  the  external  tubercle  to  the  tuberosity  of  the  fifth  metatarsal  bone.  The  inner 
portion  is  thin  and  weak  (Fig.  586). 

These  three  ligamentous  structures,  the  calcaneoscaphoid  ligament,  plantar  liga- 
ments, and  plantar  fascia  are  all  large,  strong,  fibrous  structures.  They  join  the 
anterior  and  posterior  pillars  of  the  arches  like  the  string  of  a  bow  and  prevent  them 
from  separating.  When  a  person  is  standing  at  rest  these  are  the  main  ligaments 
which  bear  the  weight  of  the  body.  The  static  weight  is  borne  by  the  ligaments  but 
the  dynamic  weight  (movements)  is  borne  by  the  muscles. 


568  ^^^^H       APPLIED   ANATOMY.  ^^^^^^^H 

THE   MUSCLES    OF   THE   FOOT.  ■HH| 

The  foot  is  acted  upon  by  long  muscles  which  come  down  from  the  leg  and 
short  muscles  which  arise  in  the  foot  itself.  Of  these  the  long  muscles  are  the  more 
important  because  they  influence  the  position  of  the  foot  itself,  whereas  the  short 
muscles  act  on  the  toes  ;  as  stated  the  movements  of  the  toes  are  of  secondary  impor- 
tance (page  562).  The  functions  of  the  muscles  are  active  or  dynamic  in  character. 
They  bear  the  weight  of  the  body  when  in  motion  and  direct  the  movements  of  the 
foot  in  locomotion.  Their  function  and  structure  are  to  be  studied  together,  as  one 
explains  the  other,  and  a  knowledge  of  them  explains  many  deformities  and  indicates 
their  treatment. 

The  long  muscles  have  three  distinct  actions  on  the  foot :  ( i )  they  support  the 
arch  of  the  foot;  (2)  they  flex  and  extend  the  foot;  (3)  they  abduct  and  adduct  the 
foot — this  latter  being  associated  with  a  certain  amount  of  rotation. 

The  action  01  the  individual  muscles  is  not  a  simple  one.  They  act  on  two 
joints,  the  ankle  and  subastragaloid.  If  the  former  is  stationary  they  abduct  and 
adduct,  if  the  latter  is  stationary  they  flex  and  extend,  but  if  both  move  then  a  com- 
bined action  of  the  muscles  is  necessary. 

For  our  purposes  we  may  divide  the  muscles  into  four  groups  of  three  each 
(page  546).  They  are  (i)  extensors,  (2)  flexors,  (3)  abductors,  (4)  muscles  of 
the  calf. 

1.  Extensor  group:  tibialis  anterior ,  exte7isor  lo7igus  halljccis,  extensor  Ion gtis 
digitorum. 

2.  Flexor  group:  tibialis  posterior,  fiexor  longus  digitornm,  flexor  loiigus 
hallucis. 

3.  Abductor  group :  peroneiis  longus,  peroneus  brevis,  pero7ieus  tertius. 

4.  Muscles  of  the  calf:  gastrocnemius,  soleus,  piantaris. 

The  Action  of  the  Muscles  in  Supporting  the  Tarsal  Arch. 

Tibialis  Anterior. — The  tendon  of  the  anterior  tibial  descends  along  the  anterior 
edge  of  the  internal  malleolus  and  inserts  into  the  lower  inner  surface  of  the  internal 
cuneiform  bone  and  base  of  the  first  metatarsal  bone. 

Tibialis  Posterior. — Its  tendon  passes  down  close  behind  the  posterior  edge  of 
the  internal  malleolus,  crosses  the  internal  lateral  ligament  of  the  ankle,  passes 
under  the  inferior  calcaneonavicular  (scaphoid)  ligament  and  in  front  of  the  susten- 
taculum tali  to  insert  into  the  tubercle  of  the  navicular  (scaphoid).  From  the  tuber- 
cle its  tendon  sends  slips  to  all  the  tarsal  bones  except  the  talus  (astragalus)  and  to 
the  bases  of  the  second,  third,  fourth,  and  sometimes  fifth  metatarsal  bones. 

Flexor  Longus  Digitorum. — Its  tendon  passes  behind  the  internal  malleolus 
immediately  posterior  to  the  tibialis  posterior  and  then  curves  around  the  susten- 
taculum tali  to  enter  the  foot,  passing  forward  to  insert  into  the  base  of  the  terminal 
phalanges  of  the  outer  four  toes. 

Flexor  Longus  Hallucis. — This  tendon  descends  across  the  middle  of  the  pos- 
terior part  of  the  ankle-joint  and  curves  forward  under  the  sustentaculum  tali.  It  is 
the  most  posterior  of  the  structures  running  behind  the  internal  malleolus.  It  lies 
deeper  than  the  tendon  of  the  flexor  longus  digitorum,  and  as  it  crosses  it  gives  to  it 
a  small  slip.      It  then  inserts  into  the  base  of  the  terminal  phalanx  of  the  big  toe. 

Peroneus  Loyigus. — This  tendon  overlies  the  tendon  of  the  peroneus  brevis  as 
it  passes  down  immediately  behind  the  external  malleolus.  It  then  winds  around 
the  outer  surface  of  the  os  calcis  behind  the  peroneal  tubercle  to  pass  obliquely 
inward  and  forward  across  the  sole  of  the  foot,  in  a  canal  formed  by  the  long  plantar 
ligament  and  a  groove  in  the  cuboid  bone,  to  insert  into  the  base  of  the  first  meta- 
tarsal bone  and  internal  cuneiform. 

Peroneus  Brevis.  — This  tendon  passes  down  behind  the  external  malleolus 
beneath  and  a  little  anterior  to  the  tendon  of  the  peroneus  longus.  It  passes  in  front 
of  the  peroneal  tubercle  and  then  goes  forward  to  insert  into  the  tuberosity  of  the 
fifth  metatarsal  bone. 


THE  FOOT. 


569 


Peroneus  Terthis. — This  tendon  descends  in  front  of  the  external  malleolus  and 
inserts  into  the  upper  surface  of  the  fifth  metatarsal  bone  near  its  base. 

The  other  muscles  of  the  leg  do  not  support  the  tarsal  arch.      In  considering- 
the  insertions  of  these  tendons  it  will  be  seen  that  the  tibialis  anterior,  peroneus 
tertius,  and  peroneus  brevis  are  practically  inserted  into  the  convexity  of   the  tarsal 
arch  and  tend  to  support  it  by  pulling 
it  upward.      The  flexor  longus  hallucis 
and  flexor  longus  digitorum  run  longitu- 
dmally  beneath  the  arch  and  so  directly 
support  it.     The  tibialis  posterior  and 
peroneus  longus,  one  from  the  inner  and 
the  other  from  the  outer  side,  meet  and 
cross  on  the  sole  of  the  foot,  thus  form- 
ing a  double  sling  immediately  beneath 
the  arch  on  which  it  rests  when  those 
muscles  contract. 

If  these  muscles,  on  which  the  arch 
directly  relies  for  its  support  when  sub- 
jected to  the  strain  of  locomotion,  are 
unable  to  meet  the  demands  made  upon 
them  then  the  strain  falls  on  the  liga- 
ments, and  as  »these  are  intended  for 
static  and  not  dynamic  purposes  they 
weaken  and  give  way  and  the  arch  de- 
scends. To  cure  such  a  condition  over 
use  must  be  avoided  and  the  strength  of 
the  muscles  is  to  be  restored  by  exercise, 
massage,  electricity,  etc. 


The  Action  of  the  Muscles  as 
Flexors  and  Extensors. 


Posterior  tibial 


Anterior  tibial 

Extensor  longus 
hallucis 

Extensor  longus 
digitorum 
Peroneus  brevis 


Peroneus  longus 
Peroneus  tertius 


Flexor  brevis 
digitorum 


The  peroneus  group  of  muscles 
exert  so  little  influence  on  flexion  and 
extension  that  in  many  cases  they  may 
be  ignored.  The  peroneus  tertius  flexes 
the  ankle,  while  the  longus  and  brevis 
extend  it.  The  common  movements  of 
the  foot  when  great  strength  is  not  re- 
quired are  performed  by  the  flexor  and 
extensor  groups  of  muscles;  the  muscles 
of  the  calf  are  not  so  much  for  adding 
to  the  kind  of  movements  as  to  the 
amount.  The  powerful  calf  muscles 
have  the  function  of  aiding  the  body  in 
maintaining  the  upright  posture  and 
especially  in  lifting  and  propelling  it 
forward  in  locomotion.  When  most  of 
the  flexors  and  extensors  are  paralyzed 
the  foot  hangs  loose  from  the  leg,  the 
so-called  flail-foot.  Weakness  of  the 
flexor  group  (tibialis  posterior,  flexor 
longus  digitorum,  and  flexor  longus  hallucis)  tends  to  favor  a  descent  of  the  arch 
with  consequent  pronation  or  eversion.  Weakness  of  the  extensors  causes  toe-drop 
and  inversion  or  supination. 

Paralysis  of  the  calf  muscles  deprives  the  posterior  pillar  of  the  arch  of  its  support 
and  the  action  of  the  flexors  and  extensors  elevates  the  arch  while  the  heel  descends, 
so  that  a  condition  of  hollow  foot  is  produced. 


Fig.  587. — The  foot  in  an  adducted  or  supinated  position. 


570 


APPLIED   ANATOMY. 


Paralysis  of  the  calf  muscles  is  not  rare,  while  that  of  the  deep  flexors  is  less 
common.  The  question  of  paralysis  must  be  studied  with  reference  to  each  individ- 
ual case,  because  the  affected  muscles  are  not  always  completely  paralyzed,  neither 
are  all  the  muscles  of  a  group. 


The  Action  of  the  Muscles  as  Abductors  and  Adductors. 


Lateral 


movements  of  the  foot  are  comparatively  weak  when  compared  with 

those  of  flexion  and  extension.  They  are 
intended  largely  to  maintain  the  balance 
or  equilibrium  and  to  adapt  the  position  of 
the  foot  to  uneven  surfaces,  etc.  Three 
muscles  act  very  distinctly  as  abductors  ; 
they  are  the  peroneus  longus,  brevis,  and 
tertius.  Two  act  as  distinct  adductors, 
viz. :  the  tibialis  anterior  and  the  tibialis 
posterior. 

The  muscles  of  the  calf  act  more  as 
abductors  than  adductors,  because  the  in- 
sertion of  the  tendo  calcaneus  (Achillis) 
is  not  directly  behind  the  ankle-joint  but 
more  to  its  outer  side. 

When  the  foot  is  deformed  in  the 
position  of  inversion,  as  in  club-foot,  the 
tibialis  anterior  and  posterior  are  usually 
contracted,  but  when  in  the  position  of 
eversion,  as  in  flat-foot,  then  spasm  of  the 
peronei  or  calf  muscles  is  frequent. 

Plantar  flexion  of  the  foot  is  a  far 
more  powerful  movement  than  extension — 
flexion  is  associated  with  adduction  or  in- 
version and  extension  with  abduction  or 
eversion ;  hence  it  is  that  inversion  is  the 
position  of  strength  and  eversion  of  weak- 
ness. Feats  of  strength  and  agility  cannot 
be  performed  by  those  who  have  markedly 
everted  feet. 


Tibialis  anterior 

Extensor  longus 
hallucis 

Extensor  longus 
digitorum 

Peroneus  tertius 

Peroneus  brevis 

Peroneus longus 


Extensor 

brevis 

digitorum 


SURFACE  ANATOMY  OF   THE 
FOOT. 


For  the  clinician  and  operator  an  exact 
knowledge  of  surface  anatomy  is  absolutely 
essential.  It  can  readily  be  acquired  be- 
cause the  various  bony  points  and  tendons 
are  usually  evident  both  to  touch  and  sight. 
Bony  Landmarks. — There  are  five 
prominent  bony  points  :  they  are  the  in- 
ternal and  external  malleoli^  the  tubercles 
of  the  OS  calcis  and  7iavictdar  (^scaphoid) 
and  the  ttiberosity  of  the  fifth  metatarsal 
bone. 

The  internal  malleolus  is  large  and  flat 
and  has  a  somewhat  rounded  lower  edge. 
It  is  above  and  anterior  to  the  external  malleolus.  Immediately  in  front  of  its  anterior 
edge  runs  the  commencement  of  the  long  saphenous  vein.  Around  its  lower  pos- 
terior border  runs  the  tendon  of  the  tibialis  posterior  muscle  on  its  way  to  the  tubercle 
of  the  scaphoid. 


Fig.   588. — The  foot  in   an   abducted  or  pronated 
position. 


THE  FOOT. 


571 


The  external  malleolus  is  more  prominent  than  the  internal,  smaller,  and  more 
pointed.  The  fibula  above  for  its  lower  fourth  is  subcutaneous.  The  tip  of  the 
external  malleolus  is  2  cm.  ( ^  in. )  below  and  behind  the  internal.  Around  its 
posterior  and  lower  edge  run  the  peroneus  longus  and  brevis  tendons. 

The  tubercles  of  the  os  calcis  can  be  felt  posteriorly  and  at  the  sides.  The 
external  surface  can  be  followed  forward,  but  the  internal  is  buried  beneath  the 
soft  tissues.  Of  the  two  tubercles  on  its  under  surface  the  internal  can  be  felt  by 
firm  pressure. 

The  tubercle  of  the  scaphoid  {navicular)  lies  on  the  plantar  rather  than  on  the 
lateral  aspect  of  the  bone.      It  can  be  felt  4  cm.  (i^  in.)  below  and  in  front  of  the 


Ankle-joint 


Internal  malleolus 


Subastragaloid  joint 
Sustentaculum  tali 


Os  calcis 


Internal  tubercle  of  the 
OS  calcis 


Tubercle  of  the  scaphoid 
Fig.   589. — Surface  anatomy  of  the  inner  side  of  the  ankle. 

internal  malleolus.  It  is  the  landmark  for  the  tarsal  joints  on  the  inner  side  of  the 
foot.  The  tibialis  posterior  muscle  runs  from  it  to  the  posterior  edge  of  the  internal 
malleolus. 

The  sustentaculum  tali  can  be  found  by  feeling  2.5  cm.  (i  in.)  below  the  inter- 
nal malleolus.      It  is  not  very  distinct. 

The  tuberosity  of  the  fifth  metatarsal  bone  is  the  large  bony  prominence  6  cm. 
{2Y2  in.)  below  and  in  front  of  the  external  malleolus.     It  is  the  guide  to  the  tarsal 


Subcutaneous  portion  of  fibula 


External  malleolu;. 

Peroneal  tubercle 

External  tubercle  of  os  calcis 


'Ankle-joint 
Astragalus 
Scaphoid 
Os  calcis 


Internal  cuneiform 
Middle  cuneiform 

External  cuneiform 

•Cuboid 


Tubercle  of  fifth  metatarsal 
Fig.   590. — Surface  anatomy  of  the  outer  side  of  the  ankle. 

joints  on  the  outside  of  the  foot.  The  tendon  of  the  peroneus  brevis  runs  from  it 
to  the  posterior  edge  of  the  external  malleolus. 

The  peroneal  spiiie  (tubercle)  can  be  felt  indistinctly  as  a  small  bony  prominence 
2.5  cm.  (i  in.)  below  and  a  little  in  front  of  the  external  malleolus.  In  front  of  it 
runs  the  peroneus  brevis  and  behind  it  the  peroneus  longus. 

The  Tendons. — It  is  difficult  to  identify  the  position  of  the  tendons,  espe- 
cially if  one  does  not  know  where  to  look  for  them. 

The  tendo  calcaneus  (Achillis)  is  usually  easily  recognized,  as  it  can  be  made 
tense,  even  in  fat,  chubby  children,  by  dorsally  flexing  the  foot. 


572  ^^^^^       APPLIED    ANATOMY. 

The  flexor  lo7igiis  digitorum  and  flexor  longiis  halliicis  lie  too  c 
the  internal  malleolus  to  be  recognized;  the  latter  is  the  more  posterior. 

The  tibialis  posterior,  on  strongly  abducting  the  foot,  can  often  be  seen  and  felt 
along  the  posterior  border  of  the  internal  malleolus  and  between  the  latter  and  the 
tubercle  of  the  scaphoid,  into  which  it  inserts. 

The  tibialis  anterior  is  the  tendon  nearest  the  anterior  edge  of  the  internal 
malleolus.  It  runs  down  to  the  internal  cuneiform  bone  about  2.5  cm.  (i  in.)  in 
front  of  the  tubercle  of  the  scaphoid. 

The  extensor  longiis  hallucis  lies  just  to  the  outside  of  the  tibialis  anterior  and 
can  often  be  made  prominent  by  flexing  the  big  toe. 

The  extensor  longiis  digitorum  tendons  at  the  ankle  lie  close  together  just  out- 
side of  the  extensor  longus  hallucis.  The  peroneus  tertius  runs  from  them  to  the 
dorsum  of  the  fifth  metatarsal  bone  a  little  in  front  of  its  base. 

T\iQ.  peroneal  tendons  can  usually  be  made  visible  by  sharply  adducting  the  foot. 
The  brevis  is  then  seen  running  back  to  the  peroneal  spine  2.5  cm.  (i  in. )  below  and 
a  little  in  front  of  the  external  malleolus  and  from  this  point  up  to  behind  the  malle- 
olus; in  thin  people  both  the  brevis  and  longus  can  be  seen  and  followed  up  the 
lower  part  of  the  fibula. 

The  soft  rounded  prominence  about  5  cm.  (2  in.)  in  front  of  the  external  malleo- 
lus is  the  extensor  brevis  digitorum  muscle. 

The  Joints. — The  ankle-joint  lies  1.25  cm.  (^  in.)  above  the  tip  of  the  inter- 
nal malleolus. 

The  midtarsal  (Chopart's)  joint  is  best  found  on  the  inner  side  of  the  foot;  here  it 
passes  immediately  behind  the  tubercle  of  the  scaphoid.  On  the  outer  side  it  is  ap- 
proximately at  the  middle  of  a  line  joining  the  external  malleolus  and  tuberosity  of 
the  fifth  metatarsal  bone.  At  this  point  there  is  frequently  a  bony  prominence 
formed  by  the  anterior  edge  of  the  os  calcis. 

The  tarsometatarsal  (Lisfranc's)  joint  is  best  found  on  the  outer  side  of  the 
foot.  It  lies  immediately  behind  the  tuberosity  of  the  fifth  metatarsal  bone,  between 
it  and  the  cuboid. 

Its  inner  extremity  can  be  found  either  by  following  up  the  first  metatarsal  bone 
from  its  head  for  about  5  cm.  (2  in.)  when  a  ridge  of  bone  will  be  felt  on  its  base,  the 
joint  being  immediately  behind  it;  or  by  identifying  the  tubercle  of  the  scaphoid  and 
allowing  2.5  cm.  (i  in.)  from  its  anterior  edge  for  the  internal  cuneiform  bone.  Its 
exact  location  is  to  be  recognized  by  pressing  with  the  edge  of  the  thumb  at  the  sus- 
pected spot  and  moving  the  metatarsal  bone  with  the  opposite  hand. 

THE   ARTERIES   OF   THE    FOOT. 

The  dorsalis  pedis  artery  runs  from  the  middle  of  the  front  of  the  ankle 
to  the  base  of  the  first  metatarsal  interspace.  The  extensor  longus  hallucis  tendon 
is  on  the  medial  side  and  the  extensor  longus  digitorum  on  the  lateral.  An  in- 
cision made  midway  between  these  tendons  exposes  the  muscular  fibres  of  the  ex- 
tensor brevis  digitorum;  this  is  pulled  to  the  outer  side  and  the  artery  will  be  found 
lying  on  the  bone  beneath.  The  extensor  brevis  digitorum  crosses  it  near  its  termi- 
nation. 

This  artery  is  rarely  the  subject  of  ligation,  but  one  frequently  endeavors  to  feel 
its  pulsation  in  order  to  determine  whether  the  artery  above  is  intact. 

The  Plantar  Arteries. — The  tibialis  posterior  divides  into  the  internal  and 
external  plantar  arteries  at  a  point  midway  on  a  line  joining  the  internal  malleolus 
and  internal  tubercle  of  the  os  calcis.  From  this  point  the  internal  plantar  artery 
runs  forward  along  the  medial  side  of  the  flexor  longus  hallucis  in  the  groove  between 
the  abductor  hallucis  and  flexor  brevis  digitorum.  It  is  much  the  smaller  of  the  two 
plantar  arteries  (Fig.  591). 

The  external  plantar  artery  runs  from  the  same  point  as  the  internal  to  the 
inner  side  of  the  base  of  the  fifth  metatarsal  bone.  To  this  point  it  lies  beneath  the 
flexor  brevis  digitorum  and  above  the  accessorius.  It  then  dips  deeper,  lying  on  the 
interossei,  and  curves  inward  to  end  in  the  communicating  artery  which  pierces 
the  base  of  the  first  metatarsal  space  to  anastomose  with  the  dorsalis  pedis. 


THE   FOOT. 


573 


It  can  be  ligated  by  making  an  incision  at  the  medial  side  of  the  base  of 
the  fifth  metatarsal  bone  between  the  flexor  brevis  digitorum  and  the  flexor  brevis 
minimi  digiti. 

Formal  ligation  of  the  plantar  arteries  is  not  often  required.  If  wounded  the 
bleeding  can  be  stopped  by  packing  the  wound,  applying  pressure,  and  elevating  the 
foot  as  high  as  possible.      Care  is  to  be  exercised  in  making  incisions  in  the  sole  of 


Princeps  hallucis  artery 

Flexor  accessorius  and 
long  flexor  tendons 

Plantar  arch 

Tendon  of  peroneus  longus 
Flexor  brevis  hallucis 
Flexor  longus  hallucis 
Internal  plantar  nerve 

Internal  plantar  artery 
Abductor  hallucis 

Internal  malleolus 

Posterior  tibial  tendon 

Flexor  longus  digitorum  ,{" 

Posterior  tibial  artery 

Posterior  tibial  nerve 


Flexor  brevis  digitorum 


Flexor  brevis 
minimi  digiti 


.\bductor  minimi  digiti 


Adductor  hallucis 

Accessorius 

— External  plantar  nerve 

—  3xtemal  plantar  artery 

Tendon  of  flexor  brevis 
r~  ligitorum 


Internal  calcaneal! 
branch  ot  posterior 
tibial 


Flexor  longus  hallucis 


Fig    591. — Plantar  arteries  and  nerves. 

the  foot  in  the  grooves  to  the  inner  and  outer  side  of  the  flexor  brevis  digitorum  for 
fear  of  wounding  the  plantar  arteries.  The  external  plantar  is,  however,  not  liable 
to  be  wounded  if  the  incision  is  made  back  toward  the  tubercle  of  the  os  calcis. 

The  plantar  arteries  usually  escape  division  in  operating  subcutaneously  on  the 
plantar  fascia  because  the  plantar  fascia  is  above  the  flexor  brevis  while  the  arteries 
are  below.  It  is  so  difflcult  to  ligate  bleeding  arteries  in  the  foot  that  it  is  usually 
better  to  pack  the  wound  with  an  antiseptic  gauze  and  elevate  the  limb. 


574 


APPLIED    ANATOMY. 


AMPUTATIONS   OF   THE    FOOT. 

The  foot  may  be  amputated  through  the  midtarsal  or  tarsometatarsal  joints. 
Ordinarily  they  give  unsatisfactory  stumps  owing  to  the  heel  being  pulled  up  by  the 
tendo  calcaneus  (Achillis),  and  the  shape  of  the  inner  part  of  the  tarsal  arch.  This 
causes  the  patient  to  walk  on  the  end  of  the  stump,  which  soon  becomes  painful. 

To  perform  these  operations  skilfully  it  is  essential  that  one  be  familiar  with  the 
lines  of  the  joints.  Plantar  flaps  are  used  because  the  skin  of  the  sole  is  tougher 
than  that  of  the  dorsum  and  the  cicatrix  is  out  of  the  line  of  pressure. 

Midtarsal  (Chopart's)  Amputation. — This  is  made  through  the  midtarsal 
joint.     The  guides  to  the  joint  are  the  tubercle  of  the  scaphoid  (navicular)  on  the 


Fig.  S92- — Chopart's  li.ivjict 
of  the  foot. 


amputation 


Plantar 
flap 


Fig.  5y,s- — i-imiaiica  larsometatarsal  amputation 
of  the  foot. 


inside  and  the  ridge  on  the  anterior  end  of  the  os  calcis,  midway  between  the  external 
malleolus  and  the  fifth  metatarsal  bone,  on  the  outer  side.  A  short  dorsal  and  a  long 
plantar  flap  are  cut.  The  plantar  flap  is  longer  on  its  inner  side  to  allow  for  the 
greater  thickness  of  the  foot  on  that  side.  It  is  easier  to  begin  the  disarticulation 
on  the  inside,  going  in  just  behind  the  tubercle  of  the  scaphoid  (navicular).  This 
part  of  the  joint  is  convex  forward.  On  reaching  the  outer  edge  of  the  astragalus 
(talus)  care  should  be  taken  not  to  slip  posteriorly  between  the  astragalus  and  os 
calcis,  but  to  continue  laterally.  The  extensor  tendons  are  to  be  sutured  to  the  end 
of  the  stump  and  frequently  the  tendo  calcaneus  (Achillis)  is  cut  in  an  attempt  to 
prevent  subsequent  elevation  of  the  heel.      (Fig.  592). 

Carelessness  may  result  in  opening  the   joint  in  front   instead  of  behind  the 
scaphoid  (navicular). 


THE  FOOT. 


575 


Tarsometatarsal  (Lisfranc's)  Amputation.  —  The  guide  to  this  joint  is 
the  tuberosity  of  the  fifth  metatarsal  bone  on  the  outer  side  and  the  ridge  on  the  base 
of  the  first  metatarsal  on  the  inner  side.  This  latter  is  about  4  cm.  (i^  in. )  in  front 
of  the  highest  point  of  the  tubercle  of  the  scaphoid. 

The  joint  is  best  entered  from  the  outer  side.  The  knife  is  to  be  passed  first 
forward  and  then  carried  inward.  Trouble  is  usually  experienced  when  the  base  of 
the  second  metatarsal  is  to  be  disarticulated.  It  lies  behind  the  others  and  some 
surgeons  advise  skipping  it  and  opening  the  first  metatarsal  joint  and  then  com- 
pleting the  disarticulation  by  opening  the  second  last.  The  sawing  off  of  the  pro- 
jecting internal  cuneiform  bone  as  proposed  by  Hey  is  objected  to  on  account  of 
weakening  the  attachment  of  the  tibialis  anterior  tendon.  The  same  precaution  is 
to  be  taken  of  making  the  plantar  flap  longer  on  its  inner  side,  as  was  advised  in 
Chopart's  amputation,  on  account  of  the  greater  depth  of  the  foot  on  this  side.  The 
line  of  the  joint  is  best  understood  by  reference  to  the  position  of  the  bones  (Fig. 
578).  Tenotomy  of  the  tendo  calcaneus  ( Achillis)  is  not  so  often  resorted  to  in  this 
amputation  as  in  that  through  the  midtarsal  joint  (Fig.  593). 


PLANTAR   ABSCESS. 

Abscesses  of  the  sole  of  the  foot  are  usually  caused  by  infected  punctured 
wounds,  or  by  the  extension  of  infection  from  wounds  of  the  toes,  etc. 

The  plantar  fascia  lies  on  the  flexor  brevis  digitorum  while  the  long  flexor 
tendons  lie  beneath  it.  A  punctured 
wound  may  perforate  the  plantar  fascia 
and  penetrate  the  flexor  brevis  which 
arises  from  its  under  surface,  yet  if  this 
muscle  is  not  entirely  traversed  by  the 
wound  the  tendons  of  the  long  flexors 
beneath  escape  infection  and  the  pus 
accumulates  beneath  the  plantar  fascia. 

Superficial  Plantar  Abscess. — 
In  the  superficial  form  of  plantar  abscess 
the  pus  tends  to  point  in  four  directions: 
(i)  it  may  come  directly  up  through  gaps 
between  the  fibres  of  the  plantar  fascia 
and  make  an  hour-glass  abscess,  a  small 
amount  of  pus  being  above  the  plantar 
fascia,  between  it  and  the  skin,  while  a 
larger  collection  is  beneath  the  fascia  in 
the  substance  of  the  muscle;  (2)  it  may 
burrow  its  way  forward  showing  between 
the  tendons  in  the  direction  of  the  webs 
of  the  toes;  (3)  it  may  appear  in  the 
groove  on  the  outer  side  of  the  foot  be- 
tween the  flexor  brevis  and  abductor 
minimi  digiti;  (4)  it  may  appear  on  the 
inner  side  of  the  foot  between  the  abduc- 
tor hallucis  and  flexor  brevis  (Fig.  594). 

Deep  Plantar  Abscess. — In  deep 
infection  the  pus  accumulates  around  the 
deep  flexor  tendons  and  beneath  the 
flexor  brevis  muscle.  Its  greatest  ten- 
dency is  to  extend  up  the  leg  by  following 
the  flexor  tendons  behind  the  internal  malleolus.  It  may  also  show  itself  in  the  grooves 
on  either  side  of  the  flexor  brevis,  or  between  the  tendons  at  the  webs  of  the  toes. 

Incision  of  Plantar  Abscess. — The  safest  way  to  open  these  abscesses  is 
by  the  method  of  Hilton,  The  skin  is  first  incised  and  the  abscess  opened  by  insert- 
ing a  pointed  haemostatic  forceps  and  opening  its  blades,  or  using  some  similar  blunt 
instrument.     This  is  done  to  avoid  wounding  the  arteries.      If  necessary  the  whole 


Following  the  flexor 
tendons  up  behind  the 
internal  malleolus 

Between  the  flexor 

brevis  and  abductor 

hallucis 

Between  flexor  brevis 

and  abductor  minimi 

digiti 

Coming  through  gaps 
in  the  fascia 


Anteriorly  between 
the  tendons  at  the 
webs  of  the  toes 


Fig.  594.- 


-Diagram  showing  the  points  of  exit  of  suppu- 
ration beneath  the  plantar  fascia. 


APPLIED    ANATOMY. 

thickness  of  the  foot  may  be  traversed  by  this  means  and  a  drainage-tube  passed 
through  from  one  side  to  the  other. 

Incisions  should  not  be  made  over  bony  points  where  they  would  be  subjected 
to  pressure.  Hence  the  heads  of  the  metatarsal  bones  and  the  prominent  outer  edge 
of  the  foot  are  avoided.  Incisions  in  the  hollow  of  the  foot  and  between  the  forward 
ends  of  the  metatarsal  bones  are  to  be  preferred.  In  opening  a  subcutaneous  col- 
lection one  should  not  be  satisfied  with  simply  incising  the  skin,  but  the  fascia  should 
be  widely  split  to  guard  against  a  larger  collection  of  pus  beneath. 

Collections  which  present  to  the  outer  side  of  the  flexor  brevis  are  to  be  opened 
a  little  distance  behind  the  base  of  the  fifth  metatarsal  bone  because  the  external 
plantar  artery  becomes  somewhat  superficial  at  its  inner  side. 


DEFORMITIES    OF   THE    FOOT. 

The  common  deformities  of  the  foot  are  those  in  which  the  parts  affected  are 
deformed  or  turned  to  an  abnormal  degree  in  the  direction  of  their  normal  move- 
ments. Thus  in  talipes  varus  the  foot  is  turned  inward,  hyperadducted;  talipes 
valgus  and  flat-foot,  turned  out,  hyperabducted ;  talipes  eqiiinus  ox  hyperextended, 
talipes  calcanetis  or  hyperflexed,  and  talipes  earns  or  increase  of  the  arch  of  the  foot. 
These  deformities  may  be  either  congenital  or  acquired,  and  it  is  not  always 
easy  to  separate  the  two.  A  deformity  may  be  thought  by  the  parents  to  have 
existed  from  birth,  when  it  may  have  been  caused  by  an  infantile  paralysis  occurring 
before  the  period  of  walking. 

Foot  deformities  likewise  possess  two  characteristics  which  are  marked,  they 
are  those  of  paralysis  or  weakness  and  contraction  or  strength.      They  are  usually 

associated  but  sometimes  separate. 
There  can  be  a  paralysis  without  con- 
traction, but  inasmuch  as  the  mus- 
cular system  is  built  on  the  principle 
of  balance  it  is  obvious  that  if  one 
muscle  or  set  of  muscles  is  paralyzed 
it  is  only  a  question  of  time  until  the 
opposing  muscles  become  contracted. 
In  a  similar  manner  if  contraction 
exists  as  the  most  prominent  element 
and  perhaps,  the  primary  one,  it  will 
usually  be  found  that  the  opposing 
muscles  and  ligaments  are  stretched 
and  weakened. 

These  conditions  furnish  the  indi- 
cations for  treatment.  Where  weak- 
ness is  the  predominant  feature  then 
support  is  to  be  given  and  contraction 
of  the  relaxed  tissue  favored.  Where 
strength  and  contraction  is  predominant  then  operations  and  forcible  measures  are 
necessary  to  overcome  them.  Also,  when  in  a  contracted  case  the  contracted  tissues 
have  been  overcome,  there  still  remains  the  weakness  of  the  opposing  tissues  to  be 
remedied.  It  may  be  possible  to  bring  the  foot  to  a  perfectly  normal  position,  but 
until  the  previously  weakened  and  overstretched  tissues  have  regained  their  tone 
normal  function  will  not  be  possible. 

While  the  deformities  may  be  simple  they  are  usually  compound  ;  thus  an 
equinus  may  be  associated  with  a  varus  or  valgus,  and  is  then  called  an  equino- 
varus  or  equinovalgus.  Cavus  or  hollow-foot  and  calcaneous  or  lowering  of  the  heel 
are  often  associated,  so  that  it  is  difficult  to  draw  a  line  separating  them. 

Talipes  Varus. — Talipes  varus  in  its  most  common  form  is  congenital  and  is 
often  associated  with  equinus  or  a  drawing  up  of  the  heel.  The  prevailing  deformity 
is  one  of  adduction,  with  a  certain  amount  of  inward  rotation  (Fig.  595).  The  mus- 
cles favoring  it  are  the  tibialis  anterior  and  tibialis  posterior ;  therefore  the  tendons 
of  these  muscles  are  sometimes  cut  to  prevent  their  drawing  the  foot  upward  and 


Pifi-   595- — Talipes  equinovarus. 


THE  FOOT.  577 

inward.  Division  of  the  plantar  fascia  is  also  often  necessary.  The  main  principles 
of  treatment  are  to  stretch  the  contracted  tissues  forcibly,  either  by  manual  or  instru- 
mental force,  and  then  maintain  the  foot  in  its  corrected  position,  often  at  first  by 
plaster  of  Paris  and  later  by  apparatus,  until  the  weakened  opposing  muscles  have 
resumed  their  functions.  This  often  takes  so  long  that  transplanting  of  tendons  has 
been  resorted  to;  thus  the  tendon  of  the  tibialis  anterior  has  been  detached  from  its 
insertion  on  the  inner  side  of  the  foot  and  transplanted  to  the  outer  side,  so  that  the 
contracting  force  on  the  inner  side  of  the  foot  is  weakened,  while  the  correcting  force 
of  the  abducting  muscles  has  been  increased. 

If  equinus  is  present  either  tenotomy  of  the  tendo  calcaneus  ( Achillis)  or  forcible 
stretching  of  it  allows  the  heel  to  descend. 

Talipes  Valgus. — In  talipes  valgus  the  foot  is  abducted  or  everted.  It  is 
sometimes  associated  with  equinus  and  sometimes  with  calcaneus.  It  is  more  usually 
an  acquired  than  a  congenital  deformity.  It  is  a  deformity  that  has  weakness  as  its 
primary  cause  and  most  marked  characteristic.  This  weakness  is  either  a  more  or 
less  general  one  affecting  the  ligaments  and  muscles,  as  shown  by  its  occurring  in 
adolescents,  or  else  primarily  a  muscular  one  caused  by  spinal  infantile  paralysis 
(anterior  poliomyelitis)  (Fig.  596). 

From  what  has  been  said  of  the  normal  movements  of  the  joints  (page  569  and 
ante)  it  is  evident  that  a  weakness  of  either  the  muscles  or  ligaments  shows  itself  first 


Fig.  596. — Paralytic  talipes  valgus.  Fig.  597. — Flat-foot. 

by  an  eversion  of  the  foot  called  the  pronatcd  foot  which  is  followed  by  a  descent  of 
the  tarsal  arch  or  flat-foot  and  later  by  a  more  complete  eversion  or  pes  valgus. 
They  are  the  three  stages  of  the  same  process. 

When  a  young  person  with  apparently  normal  feet  is  subjected  to  excessive 
strain,  as  by  long  standing,  etc.,  the  muscles  and  ligaments  are  unable  to  bear  the 
burden.  The  muscles  give  way  first  and  the  foot  everts,  mainly  at  the  subastragaloid 
joint,  thus  is  produced  the  pronated  foot.  The  patient,  unable  to  support  the  body 
weight  sufficiently  on  the  weakened  muscles,  relaxes  them  and  allows  the  body 
weight  to  be  borne  on  the  ligaments.  This  excess  of  weight  on  the  ligaments  sup- 
porting the  arch  causes  them  to  give  way  and  the  arch  descends  and  flat-foot  results. 
The  process  often  stops  here  in  the  adolescent  form  or  even  if  rheumatism  is  the 
weakening  element  (Fig.  597). 

When  paralysis — usually  of  the  extensors  and  tibialis  posterior — is  the  cause, 
then  the  ligaments  not  being  so  much  affected  may  maintain  the  arch  intact,  but  the 
whole  foot  is  drawn  outward  by  the  peroneal  and  flexor  muscles,  aided  also  by  the 
centre  of  gravity  being  shifted  inward.  The  deformity  is  increased  by  walking  and 
a  true  valgus  results. 

In  the  pronated  foot  and  flat-foot  of  adolescents  pain  is  often  marked  so  that  the 
relaxation  of  the  inverting  muscles  is  often  accompanied  by  spasm  of  the  everting 
muscles  and  the  peronei  muscles  are  frequently  found  markedly  contracted.  In 
paralytic  valgus  the  eversion  of  the  foot  relaxes  the  peronei  and  they  gradually 
shorten.  It  should  be  noted  that  the  contraction  of  the  peroneal  muscles  in  one  case 
is  active,  in  the  other  passive. 
37 


578 


APPLIED  ANATOMY. 


Treatment. — In  painful  pronated  and  flat  feet  the  contracted  muscles  can  be 
relaxed  by  perfect  rest  in  bed.  Next  the  arch  can  be  supported  by  pads  or  plates 
beneath  the  instep  and  the  weakened  muscles  strengthened  by  massage,  electricity, 
or  appropriate  exercises  while  the  exciting  cause  of  overwork  is  removed.  In  para- 
lytic valgus,  the  foot  may  be  brought  straight  by  forcible  stretching  and  held  there 
by  appropriate  apparatus;  or  an  artificial  ankylosis  (arthrodesis)  of  the  subastragaloid 


598. —  Talipes  equinus. 


and  ankle-joints  may  be  made  to  hold  the  foot  in  position;  or  the  peroneal  or  othei 
tendons,  on  the  outer  side  of  the  foot,  may  be  transplanted  to  the  inner. 

Talipes  Equinus. — This  sometimes  exists  as  a  pure  form  but  it  often  accom- 
panies varus  and  sometimes  valgus.  It  is  caused  by  a  paralysis  of  the  extensor 
muscles.  The  tendo  calcaneus  is  contracted  and  the  patient  walks  on  the  toes.  By 
division  or  lengthening  of  the  tendo  calcaneus  and  forcible  flexion  of  the  foot  the 


Fig.  S99. — Talipes  calcaneus. 


Fig.  600. — Talipes  cavus. 


heel*  may  be  brought  down  but  the  foot  will  "  flop"  in  a  more  or  less  flail-like  con- 
dition from  the  leg.  To  remedy  this  either  an  apparatus  is  employed  or  some- 
times the  peroneal  muscles  or  some  of  the  flexor  tendons  are  brought  forward  and 
the  effort  made  to  have  them  fulfil  the  function  of  the  paralyzed  extensors,  which 
latter  may  also  be  shortened  (Fig.  598). 

Talipes  Calcaneus  and  Talipes  Cavus. — These  result  from  paralysis  of  the 
muscles  of  the  calf  or  of  most  of  the  flexor  and  extensor  muscles  (Figs.  599  and  600 "i 


THE  FOOT. 


579 


If  the  calf  muscles  are  paralyzed  the  contraction  of  the  tibialis  anterior  and  tib- 
ialis posterior  pull  up  the  arch  and  the  contraction  of  the  flexor  brevis  digitorum 
pulls  the  pillars  closer  together,   therefore  the 
heel  descends,  the  arch  ascends,  and  the  plantar 
ligaments  contract.     If  the  extensor  muscles  are 
also  paralyzed  the  toes  drop  and  the  anterior  de-  j 

formity  is  increased. 

The  treatment  of  this  condition  is  as  yet 
not  entirely  settled.  The  plantar  fascia  must 
be  divided  and  the  pillars  of  the  arch  separated 
and  the  arch  depressed  by  forcible  manual  or 
instrumental  means.  To  retain  the  foot  in  its 
corrected  position  the  tendo  calcaneus  is  some- 
times shortened.  Jones  makes  an  arthrodesis 
(ankylosis)  of  the  midtarsal  and  ankle-joints  ; 
Whitman  excises  the  astragalus,  pushes  the  foot 
back,  and  transplants  the  peroneal  and  posterior 
tibial  tendons  into  the  os  calcis.  The  writer 
makes  a  transverse  section  through  the  sub- 
astragaloid  joint,  pushes  the  foot  back,  and  if 
necessary  transplants  the  peroneal  and  poste- 
rior tibial  tendons  into  the  os  calcis. 

Hallux  valgus  is  a  subluxation  of  the  big 
toe  outward.  There  is  usually  a  deformity  of 
the  bone,  the  joint  surface  of  the  head  of  the 
first  metatarsal  being  inclined  obliquely  out.  As 
the  toe  becomes  displaced  outward  the  extensor 
hallucis  longus  by  its  contraction  tends  to  in- 
crease the  deformity.  On  the  side  of  the  head  / 
of  the  protruding  metatarsal  bone  a  bursa  de- 
velops and  becomes  painful,  forming  a  bunion. 
This  bursa  sometimes  suppurates  (Fig.  6oi). 

In  some  cases  hallux  valgus  is  due  ap- 
parently to  ill-shaped  shoes,  but  in  many  cases, 
and  these  the  worst,  a  rheumatic-gouty  condition 
is  the  main  factor.  In  treatment  the  articular 
surface  of  the  head  of  the  first  metatarsal  bone  is 
first  resected.  If  desired  a  fascial  flap  can  be  in- 
terposed. This  enables  the  toe  to  be  brought 
straight.  To  keep  it  straight  the  tendon  of  the  extensor  hallucis  is  displaced  inward 
and  sewed  in  position  with  catgut,  so  that  by  its  contraction  it  keeps  the  toe  from 
again  going  outward. 

THE  TOES. 

The  toes  are  shorter  than  the  fingers  and  are  not  so  often  injured.  When 
injured  or  diseased  healing  may  be  delayed  by  the  constant  motion  to  which  they 
are  subjected.  For  this  reason  rest  should  be  enforced  in  obstinate  cases  by  the 
application  of  bandages  or  splints. 

Ingrown  Nail. — This  usually  affects  the  big  toe.  It  is  caused  commonly  by 
the  irritation  and  pressure  of  badly-shaped  shoes.  To  cure  it  the  side  of  the  nail 
is  sometimes  removed.  In  so  doing  the  nail  should  be  removed  well  beyond  the 
skin  margin  at  the  matrix  otherwise  it  is  reproduced  in  a  distorted  form.  It  requires 
several  months  for  a  new  nail  to  grow  out  from  the  matrix.  Packing  cotton  soaked 
in  a  solution  of  nitrate  of  silver,  lo  grains  to  the  ounce,  beneath  the  edge  of  the  nail 
destroys  the  infection,  lessens  the  pressure,  and  usually  relieves  the  acute  trouble  in  a 
few  days. 

Hammer  Toe. — This  is  a  contraction  of  one  of  the  toes,  most  often  the  second. 
The  deformity  is  usually  consecutive  to  the  use  of  badly  fitting  shoes.  Walsham 
("  Deformities  of  the  Human  Foot"),  Shattock,  and  Anderson  believe  it  to  depend 


Fig.  6oi.- 


Hallux  valgus,  showing  the  position 
of  the  bones. 


58o 


APPLIED    ANATOMY. 


on  a  contraction  of  the  plantar  fibres  of  the  lateral  ligaments  and  glenoid  ligament  on 
the  under  side  of  the  joint.  Others  hold  it  to  be  a  contraction  of  the  tendons.  In 
treatment  both  conditions  ha\e  to  be  considered.  On  pulling  the  toes  the  extensor 
tendon  is  put  on  the  stretch,  it  should  be  divided,  the  remaining  contractures  are 
then  either  cut  or  broken  by  forcible  stretching  and  the  toe  kept  straight  by  band- 


FiG.  602. — Hammer-toe.     (From  author's  sketch.) 


aging  until  all  tendency  to  contraction  has  been  corrected.    As  a  last  resort  resection 
of  the  joint  is  performed  (Fig.  602). 

Luxation  of  the  Toes. — The  big  toe  may  become  dislocated  by  direct  vio- 
lence; the  lesion  is  often  compound.  The  displacement  is  most  often  backward  on 
the  dorsum  of  the  metatarsal  bone.  When  the  injury  is  not  compound  the  same  dif- 
ficulty may  be  experienced  in  reducing  it  as  occurs  in  dislocation  of  the  thumb.  The 
cause  is  the  same.  The  head  of  the  metatarsal  bone  becomes  caught  in  the  fibrous 
tissues  of  the  capsule  and  between  the  two 
heads  of  the  flexor  brevis  hallucis  muscle. 
These  each  contain  a  sesamoid  bone.  The 
detachment  of  one  of  these  heads  from  the 
base  of  the  first  phalanx  may  be  necessary 
before  replacement  can  be  effected. 

Dislocation  of  the  other  individual  toes 
is  not  nearly  so  rare  as  it  is  thought  to  be. 
It  results  from  jumping  from  a  height  and 
landing,  perhaps  on  an  uneven  surface,  with 
the  toes.  The  proximal  phalanx  may  be 
displaced  upon  the  metatarsal  bone  and  the 
resulting  pain  is  often  considered  to  be  merely 
a  sprain. 

The  head  of  the  affected  metatarsal  bone 
can  be  felt  projecting  in  the  sole,  the  toe  is 
shortened  and  the  space  between  it  and  the 
adjacent  one  usually  increased;  but  the  diag- 
nosis is  difficult  and  is  best  established  by 
means  of  a  skiagraph.  Reduction  is  difficult 
and  even  when  accomplished  is  not  apt  to  re- 
main (Fig.  603).    Resection  may  be  required. 

Metatarsalgia  or  Morton's  Disease. 
— This  is  a  painful  affection  of  one  of  the  meta- 
tarsophalangeal joints,  usually  the  fourth.  Its 
pathology  is  not  settled,  but  treatment  is  based 
on  the  supposition  that  the  heads  of  the  metatarsal  bones  become  pressed  together, 
usually  by  tight  shoes.  Relief  is  often  afforded  by  separating  the  toes  with  cotton; 
by  winding  adhesive  plaster — several  thicknesses — around  the  affected  toe;  by  sup- 
porting the  arch  by  pads  or  plates;  by  inserting  a  narrow  longitudinal  pad;  or  by 
resection  or  amputation. 

Resection  of  the  Metatarsophalangeal  Joint. — In  hallux  valgus  resection 
of  the  head  of  the  metatarsal  bone  may  give  rise  to  a  stiff  joint.  If  the  ankylosis  is 
in  a  somewhat  extended  position,  walking  may  not  be  impaired. 


Fio.  603. — Dorsal  luxation  of  the  proximal 
phalanx  of  the  second  toe.  Notice  the  shorten- 
ing of  the  toe,  its  separation  from  the  third  toe. 
and  the  fulness  over  the  head  of  the  metatarsal 
bone.      (From  a  sketch  by  the  author.) 


THE  FOOT. 


S8i 


Excision  of  these  joints  may,  and  often  does,  give  rise  to  a  flail-like  condition. 
The  affected  toe  is  deprived  of  its  support  and  becomes  displaced.  Sometimes  it 
gets  beneath  the  adjoining  toes  and  pain  is  caused  by  their  superincumbent  pressure. 
In  other  cases  the  toe  is  squeezed  up  above  the  level  of  the  adjoining  ones  and  is 
rubbed  by  the  shoe  above,  causing  painful  corns.  In  either  case  the  toe  affected  is  a 
source  of  misery  and  not  infrequently  may  require  to  be  amputated.  For  these 
reasons  excisions  are  seldom  resorted  to  except  in  cases  of  hallux  valgus. 

Amputation  of  the  Toes. — Amputation  of  the  phalanges  does  not  cause  serious 
disability,  but  the  loss  of  the  head  of  the  first  metatarsal  bone  seriously  weakens  the  foot. 


Fig. 


604. — Amputation   of   a   toe   at   the    metatarsophalangeal  joint,  with   lateral   flaps,   showing    method  of 

disarticulating. 


Amputation  of  the  outer  four  toes  at  the  metatarsophalangeal  joint  is  a  diffi- 
cult operation  because,  unless  one  is  well  informed,  it  will  be  hard  to  strike  the  joint. 
It  should  be  sought  about  i  cm.  (|  in.)  behind  the  web  on  the  dorsal  aspect,  and 
if  approached  on  the  plantar  aspect  especial  care  is  to  be  exercised  not  to  go  too 
far  back  and  search  for  it  on  the  neck  of  the  metatarsal  bone  (Fig.  604).  As  in  the 
hand  so  also  in  the  foot  when  the  proximal  phalanx  is  bent  the  prominence  (or 
knuckle)  is  formed  by  the  head  of  the  proximal  (metatarsal)  bone. 


FROZEN  SECTIONS. 


I 


FROZEN   SECTIONS. 


585 


Frontal  sinus 

Pituitary  body 
Sphenoidal  sinus 

Uvula 

Pharynx 

Hyoid  bone 

Thyroid  cartilage 

Cricoid  cartilage 

Trachea 

Thyroid  gland 

Left  innominate  vein 

Angle  of  sternum 

Aorta 

Right  ventricle 

Diaphragm 
Xiphosternal  articulation 
Ensiform  cartilage 
Liver 
Transverse  colon- 
Stomach 


Umbilicus- 


Bladder 

Symphysis  pubis 
Prostate  gland 


'Longitudinal  sinus 

-Lateral  ventricle 

Corpus  callosum 
Foramen  of  Monro 
Third  ventricle 

Fourth  ventricle 

Atlas 

Axis 

Seventh  cervical  vertebra 

CEsophagus 

Second  thoracic  vertebra 

Fifth  thoracic  vertebra 

Right  bronchus 
Pulmonary  artery 
-Left  auricle  (atrium) 

Cardiac  end  of  oesophagus 
Spigelian  lobe  of  liver 

Pancreas 

First  lumbar  vertebra 

Third  portion  of  duodenum 


Promontory  of  sacrum 


Rectum 


Tip  of  coccyx 


Fig.  60s. — Median  sagittal  section. 


586 


APPLIED   ANATOMY. 


Trapezius 
Supraspinatus 


Clavicle 

Subclavian  artery 
Subclavian  vein 

First  rib 


Gastrosplenic  omentum 

Spleen 


Pancreas 
Eleventh  rib 


Kidney 


Quadratus  lumborum 


Gluteus  medius, 


Gluteal  vessels. 


Gluteus  maximus. 


Stomach 

Fifth  rib 

~;t Transverse  mesocolon 

\"V^ — -Sixth  rib 

1,  ~~  Transverse  colon 
"-  Seventh  rib 


Iliacus 


Head  of  femur 


^i^'i'''' 


Fig.  606. — Sagittal  section  through  about  the  middle  of  the  left  clavicle. 


FROZEN   SECTIONS. 


587 


Cerebral  vein 
Longitudinal  sinus 


Medial  surface  of 
cerebral  hemisphere 


Septum  lucidum 

Rostrum 

Frontal  sinus 

Anterior  commissure 

Middle  commissure 

Optic  chiasm 

Pituitary  body 

Sphenoidal  sinus 

Basilar  artery 

Pharyngeal  tonsil 

Uvula 

Atlas 


Odontoid  process 
of  axis 


Hyoid  bone 

Epiglottis 

Thyroid  cartilage 

Cricoid  cartilage 


Pacchionian  bodies 


Choroid  plexus 


Foramen  of  Monro 

Thalamus 
Splenium 


I       Pineal  body 


V^ein  of  Galen 
Post,  commissure 
Corpora 
quadrigemina 
Aqueduct  of  Sylvius 
Straight  sinus 
Mammillary  body 

Cerebral  peduncle 

Torcular  herophili 

Fourth  ventricle 

Occipital 

protuberance 


Third  cervical 
vertebra 


Fourth  cervical 
vertebra 


Fifth  cervical 
vertebra 


Sixth  cervical 
vertebra 


Fig.  607. — Median  sagittal  section  of  the  head  and  neck. 


588 


APPLIED   ANATOMY. 


Anterior  jug- 
ular vein 


Thyroid 
cartilage 

Thyroid    gland 

Internal 

jugular  vein 

Common 

carotid  artery 

Vagus  nerve 

External 

jugular  vein 


Vertebral 
artery  and  vein 


Sternohyoid 
Sternomastoid 

Sternothyroid 
Thyrohyoid 

Crico-arytenoid 
Omohyoid 

Inferior 
constrictor 

CEsophagus 

Scalenus  anticus 

Scalenus  medius 

Scalenus  posticus 

Trachelomastoid 

Levator  scapulae 

Trapezius 

Complexus 

Splenius 

Semispinalis  and 
multifidus 


Fig.  608. — Transverse  section  through  the  intervertebral  cartilage  between  the  fifth  and  sixth  cer\'ical  vertebrae. 


FROZEN    SECTIONS. 


589 


Thyroid  gland 


Internal  jugular  vein 


Innominate 
artery 


Clavicle 


m  - 

Coracoid  process  -&^. 

Subclavian    ^ff  "^ 
artery  and  vein 


Subclavian  vein 

Coracoid 
process 

Subclavian 
artery 


Pulmonary  vein 
Left  lung 
Left  ventricle 


Tenth  rib 


First  lumbar 
vertebra 


Colon 


Second  lumbar 
vertebra 


Third  lumbar 
vertebra 


Pancreas 
Suprarenal  gland 
Ureter 
Renal  artery 
Renal  vein 

Psoas  muscle 


Fourth  lumbar  vertebra 

Fig.  609. — Coronal  section  through  the  thorax- 


590 


APPLIED   ANATOMY. 


Trapezius 

Supraspinatus 

Spine  of  scapula 

Deltoid 
Infraspinatus. 

Teres  minor. 

Teres  major- 
Latissimus  dorsi 


Clavicle 

Coracoid  process     • 

Deltoid 

Head  of  humerus 

Cephalic  vein 

Pectoralis  major 

Coracobrachialis  and 
short  head  of  triceps 

Circumflex  (axillary)  nerve 
Posterior  circumflex  artery 
Axillary  vein 
Cords  of  brachial  plexus 

Axillary  artery 


Fig.  6io. — Sagittal  section  through  the  left  shoulder. 


Brachialis  anticus 

Humerus 
Musculospiral  (radial)  nerve 

Profunda  artery 
Triceps 


Biceps 


Brachial  artery 

Median  nerve 

Internal  cutaneous  nerve 

Basilic  vein 

Ulnar  nerve 


4 


Fig.  6ii. — Transverse  section  through  the  middle  of  the  arm. 


FROZEN    SECTIONS. 


591 


Brachialis  anticus 

Musculospiral  (radial)  nerve 
Profunda  artery 

Plumerus 
Triceps  • 


•*►- 


Biceps 

Brachial  artery 
Median  nerve 
IJasilic  vein 

-Ulnar  nerve 


Fig.  612. — Transverse  section  through  the  lower  third  of  the  ; 


Median  cephalic  vei: 
Biceps 
Brachioradialis 
Extensor  carpi  radialis  longio 
Musculospiral  (radial)  nerve 


Humerus;  outer  condyle 


Anconeu 


Median  basilic  vein 
Brachial  artery 

Pronator  radii  teres 

Median  nerve 

Brachialis  anticus 


Flexor  carpi  ulnaris  and 
other  flexors 


Olecranon  process 


Fig.  613. — Transverse  section  through  the  olecranon  process. 


Median  basilic  vein 

Radial  artery 

Brachioradialis 

Ulnar  artery 

Biceps 

Extensor  carpi  radialis  longior 

Head  of  radius 


Supinator  (brevis) 

Extensor  carpi  ulnaris  and 
extensor  communis  digitorum 


Pronator  radii  teres 
Median  nerve 
■Flexor  carpi  radialis 
Flexor  sublimis  digitorum 
Brachialis  anticus 
Ulnar  nerve 
Flexor  carpi  ulnaris 

Ulna 


Anconeus 
Fig.  614. — Transverse  section  through  the  head  of  the  radius. 


592 


APPLIED   ANATOMY. 


Flexor  carpi  radialis 

Radial  artery 

Radial  nerve 

Brachioradialis 

Extensor  carpi  radialis  longior 

Pronator  radii  teres 

Extensor  carpi  radialis  brevior 

Radius 

Extensor  communis  digitorum 
Supinator  (brevis) 

Extensor  ossis  metacarpi  pollicis 


Palmaris  longus 
Flexor  sublimis  digitorum 
Median  nerve 
Flexor  carpi  ulnaris 
Ulnar  nerve 


Ulnar  artery 

Flexor  profundus  digitorum 
Anterior  interosseous 
nerve  and  artery 

Ulna 

Anconeus 

Extensor  carpi  ulnaris 


Fig.  6 is. — Transverse  section  through  the  upper  third  of  the  forearm. 


itJlnar  artery 


Palmaris  longus. 

Flexor  sublimis  digitorum 

Median  nerve 

Flexor  carpi  radialis 

Brachioradialis 

Radial  nerve 

Radial  artery 

Extensor  carpi  radialis  longior 

Extensor  carpi  radialis  brevior- 

Radius 
Extensor  ossis  metacarpi  pollicis 

Extensor  communis  digitorum 


Ul 


nar  nerve 


Flexor  carpi  ulnaris 
Flexor  profundus  digitorum 


Ulna 

Extensor  longus  pollicis 

Extensor  carpi  ulnaris 

Extensor  minimi  digiti 


Fig.  6i6. — Transverse  section  about  the  middle  of  the  forearm. 


Palmaris  longus 
Flexor  sublimis  digitorum 

Flexor  carpi  radialis' 
Radial  artery 

Brachioradialis 

Radial  nerve 

Extensor  carpi  radialis  longior 

Extensor  carpi  radialis  brevior 

Radius 

Extensor  ossis  metacarpi 
pollicis  and  extensor  brevis  pollicis 

Extensor  longus  pollicis 


Median  nerve 

Flexor  carpi  ulnaris 

Ulnar  artery  and  nerve 

Flexor  profundus  digitorum 
Pronator  quadratus 
Ulna 

Extensor  indicis 

Extensor  carpi  ulnaris 

Extensor  minimi  digiti 
Extensor  communis  digitorum 


Fig.  617. — Transverse  section  of  upper  part  of  lower  third  of  forearm, 


FROZEN   SECTIONS. 


593 


Plexor  sublimis  digitorum 


Palmaris  longus 


Median  nerve 
Flexor  carpi  radialis 


Superficial  volar  artery 

Radial  artery 

Extensor  ossis  netacarpi 

pollicis  and  extensor 

brevis  pollicis 

Styloid  process,  radius 
Extensor  carpi 
radialis  longior 
Extensor  carpi 
radialis  brevior 
Extensor  longus  pollicis  — 


Extensor  communis  digitorum 

Fig.  6i8. — ^Transverse  section  through  the  wrist-joint. 


ylJlnar  artery 
Ulnar  nerve 
Flexor  carpi  ulnaris 


Flexor  profundus 
"digitorum 

Semilunar 

Scaphoid 

.Extensor  carpi  ulnaris 

Extensor  minimi  digiti 


Transversalis 
Internal 
'oblique 


Fig.  619. — Horizontal  transverse  section  through  the  body  of  the  fourth  lumbar  vertebra. 


Psoas  muscle 
Spinal  cord 


Highest  part  of 
iliac  crest 

Quadratus 
lumborum 

Erector  spins 
(sacrolumbalis) 


38 


594 


APPLIED   ANATOMY. 


Femoral  artery 


Femoral  vein 


Anterior  crural  nerve 


Sartorius 

Iliacus 

Rectus  femoris 

Tensor  fasciie  femoris 

Gluteus  minimus 

Gluteus  medius 


\(lductor  longus 
Lymph-node  and  fat 
Gracilis 

Adductor  brevis 
Pectineus 

Obturator  externus 
I  schiocavernosu* 
Obturator  intemus 

Gluteus  maximus 

Sciatic  artery 
Small  sciatic  nerve 


^Sciatic  nerve 

Fio.  620. — Oblique  section  of  the  upper  part  cf  thigh  parallel  to  and  just  below  Poupart's  liijament. 


Internal  or  long  saphenous  vein 


Femoral  artery. 


Profunda  vessels 

Rectus 

Deep  external 
circumflex  art. 

Vastus  intemus 

Crureus. 

Vastus  externus. 

Femur, 


Sciatic  artery 


Gracilis 
Adductor  longus 

Adductor  brevis 
Femoral  vein 
Adductor  magnus 


\      ,  ^Semimembranosus 


4-Semitendinosus 


Biceps 
Sciatic  nerve 


Gluteus  n-.aximus 


Fig.  621. — Transverse  section  of  thigh  high  up  through  Scarpa's  triangle. 


FROZEN    SECTIONS. 


595 


Sartorius 


Anterior  ci-ural  nerve 

Rectus 
Vastus  internus 

Femur 

Crureus 

Vastus  externus 


Internal  or  long 
saphenous  vein 


Femoral  artery 

Gracilis 
Adductor  longus 

Adductor  magnus 
Semimembranosus 

Semitendinosus 
Sciatic  nerve 


Biceps 


Sartorius 

Vastus  internus 

Femoral  artery 

Femoral  vein 


Fig.  622. — Section  of  thigh  about  at  the  apex  of  Scarpa's  triangle. 


Internal  or  long  saphenous  vein 


Vastus  externus 


Gracilis 

Adductor  longus 
Adductor  magnus 
Semimembranosus 


— I—  Semitendinosus 

'f —  Sciatic  nerve 
Biceps 


Fig.  623. — Section  of  thigh  about  the  middle.  ' 


Vastus  internus 
and  crureus 


Rectus  femoris 


Femur 


Vastus  externus 
Crureus 


Internal  or  long 
saphenous  vein 


Sartorius 
Gracilis 

Femoral  artery 
Femoral  vein 


Semimembranosus 
Semitendinosus 
Sciatic  nerve 
Long  head  of  biceps 
Short  head  of  biceps 


Adductor  magnus 

Fig.  624. — Section  of  thigh  through  its  lower  third. 


596 


APPLIED    ANATOMY. 


Patella 


Knee-joint  cavity 


Knee-joint 

Inner  head  of 
gastrocnemius 

Sartorius 

Internal  or  long 

saphenous  vein 

Gracilis 

Semimembranosus 

Semitendinosus 


Bursa 


\ —  Femur 


Internal  popliteal  (tibial)  nerve 

Fig.  625. — Transverse  section  through  the  patella. 


Outer  head  of 
gastrocnemius 

Popliteal  artery 

Popliteal  vein 

Biceps 

External  popliteal 
(fibular)  nerve 


Tibia 


Tibialis  posterior. 

Long  or  internal 
saphenous  vein 

Extensor  longus  digitorum 
Posterior  tibial  artery 
Posterior  tibial  nerve 

Peroneal  artery 


Gastrocnemius 


Tibialis  anterior 

Extensor  longus  digitorum 
Peroneus  longus 

Anterior  tibial  artery 
Anterior  tibial  nerve 

Fibula 

Soleus 

Plantaris 


Fig.  626. — Section  through  upper  third  of  leg. 


FROZEN   SECTIONS. 


597 


Tibia 

Flexor  longus  digitorum 

Internal  saphenous  vein 
Posterior  tibial  artery 
Posterior  tibial  nerve 

Plantaris 
Gastrocnemius 


Tibialis  anterior 
Anterior  tibial  nerve 
Extensor  longus  digitorum 
Anterior  tibial  artery 
Peroneus  longus  and  brevis 
Extensor  longus  hallucis 
Tibialis  posterior 
Fibula 

Peroneal  artery 
Flexor  longus  hallucis 

Soleus 


Fig.  627. — Transverse  section  through  the  middle  of  the  leg. 


Tibialis  anterior 
Anterior  tibial  artery 

Tibia 


Tibialis  posterior 

Flexor  longus  digitorum 

Posterior  tibial  artery 

Posterior  tibial  nerve 

Flexor  longus  hallucis 


Extensor  Jongus  hallucis 
Extensor  longus  digitorum 

Peroneal  artery 

Fibula 

Peroneus  longus 
Peroneus  brevis 


Tendo  calcaneus  (Achillis) 
and  gastrocnemius 


Fig.  628. — Transverse  section  through  the  lower  third  of  the  leg. 


APPLIED   ANATOMY. 


Posterior  tibial  nervc' 

Posterior  tibial  veins. 

Posterior  tibial  artery 

Flexor  longus  digitorum 

Tibialis  posterior 


Tibia 


Extensor  longus  hallucis 
Tibialis  anterior 


Tendo  Achillis 

External  or  short 
saphenous  vein 
Flexor  longus  hallucis 

Peroneus  brevis 
Peroneus  longus 

Fibula 


Extensor  longtis 
digitorum 


Fig.  629. — Transverse  section  through  the  anklo 


FROZEN    SECTIONS. 


599 


Gastrocnemius 

Soleus 

■Tibialis  posterior 

Flexor  longus  hallucis 


Tendon  of  flexor  longus  hallucis 

Sustentaculum  tali 

Os  calcis 

Flexor  accessorius 

External  plantar  artery 
Flexor  brevis  digitorum 

External  plantar  nerve 

Flexor  longus  digitorum 

Internal  plantar  nerve 


Flexor  brevis  hallucis 


Fig.  630. — Anteroposterior  section  through  the  tibia  and  first  metatarsal  bone. 


6oo 


APPLIED  ANATOMY. 


Extensor  longus  digitorum 


Anterior  tibial 


Peroneus  longus 


Peroneus  brevis 


Extensor  longus  hallucis 


Tibialis  posterior- 


Astragalus 


Flexor  longus  digitorum 

Flexor  longus  hallucis 

Abductor  hallucis 

Accessorius- 

Flexor  brevis  digitorum 


-Os  calcis 


-Abductor  minimi  digiti 


INDEX. 


Abdomen,  370 

abdominal  incisions,  381 
abdominal  ring,  external,  377,  385 

internal,  386 
fascia  of,  superficial,  374 

transversalis,  399 
herniae  of  (see  Hernia) 
Hesselbach's  triangle,  387 
inguinal  canal,  385 
interior  of,  396 
lines  of,  371 

linea  alba,  371 
linese  albicantes,  372 
linese  semilunares,  372 
lineae  transversae,  372 
lumbar  region  of  (see  Lumbar) 
incisions,  395 

longitudinal,  395 
oblique,  396 
McBurney's  point,  374 
muscles  of,  375 
nerves  of,  380 
regions  of,  370 
surface  anatomy  of,  370 
vessels  of,  374 
viscera  of,  399 

position  of,  372,  399 
walls  of,  374 

lymphatics  of,  380 
nerves  of,  380 
vessels  of,  378 
arteries,  378 
veins,  380 
Abdominal  ring,  external,  377,  385 

external  pillar  of,  377,  385 
intercolumnar  fibres  of,  377,  386 
internal  pillar  of,  377,  385 
internal,  386 
Abdominoscrotal  opening,  375 

Abducens  nerve,  injury  to,  in  fractures  of  skull,  20 
Abscess  of  axilla,  264 

incision  for,  264 
Bezold'b,  90 
of  breast,  185 
cerebellar,  13 
cerebral,  44 
of  fingers,  366 
of  hand,  365 

beneath  palmar  fascia,  365 
involving  the  fingers,  366 
involving  sheaths  of  tendons,  366 
of  hip,  516 
ischiorectal,  476 
of  kidney,  428 

points  of  pointing  of,  428 
of  liver,  420 
lumbar,  394 
of  neck,  153 

influence  of  cervical  fascia  on,  154 
of  orbit,  75 
palmar,  365 
of  pancreas,  423 

evacuation  of,  423 
of  parotid  gland,  53 
incisions  for,  54 


Abscess,  peritonsillar,  114 
plantar,  575 
deep,  5  75 
incision  for,  575 
superficial,  575 
in  posterior  cervical  triangle,  156 
of  prostate,  451 
psoas,  481 

retropharyngeal,  90.  116,  156 
of  scalp,  5 

subaponeurotic,  6 
subcutaneous,  5 
subpericranial,  6 
subdiaphragmatic,  420,  423 
subdural,  90 
submammary,  185 
in  tendon  sheaths  of  hand,  366 
of  testicle,  469 
Acetabulum,  501 
Achilles'  tendon,  551 

action  in  fractures  of  tibia,  551 
tenotomy  of, 

in  fractures  of  the  tibia,  552. 
in  Pott's  fracture,  558 
Acromioclavicular  joint,  222 

ligament,  222 
Adenoids,  122 

removal  of,  122 
Aditus,  88 

Air-passages,  operations  on,  161 
Alcock's  canal,  474,  476 
Allantois,  371, 

stalk  of,  38"2 
Allis: 

method  of  reduction  of  dislocation  of  hip,  512 
method  of  releasing  sciatic  nerve,  514 
Ampulla  of  Vater,  407 
stone  in,  422 
Amputation 

of  ankle,  559 

Pirogoff's,  560 
Syme's,  559 
of  arm,  275 
at  elbow,  302 
of  fingers,  369 

metacarpophalangeal,  369 
of  foot,  574 

midtarsal  (Chopart's),  574 
tarsometatarsal  (Lisfranc's),  575 
of  forearm,  326 

through  lower  third,  327 
through  middle  third,  327 
through  upper  third,  327 
at  hip- joint,  532 
interscapulothoracic,  250 
at  knee-joint,  544 
of  leg,  552 
of  penis,  466 
of  shoulder- joint, 

flap  method,  247 

Dupuytren's,  247 
Lisfranc's,  248 
racket  method,  248 

Larrey's,  248 
Spence's,  249 

601 


6o2 


INDEX. 


Amputation  of  thigh,  532 
of  thumb,  368 

carpometacarpal,  369 
metacarpophalangeal,  369 
of  toes,  581 
at  wrist,  347 
Anal  canal  (see  Intestine,  large) 
fissures,  443 

triangle  (see  Male  perineum) 
Anconeus  muscle,  286 
Anderson  and  Makin,  method  of  locating  fissures 

of  brain,  42 
Aneurism  of  aorta, 
arch,  210 
ascending,  208 
descending,  210 
arteriovenous,  7 
cirsoid,  of  scalp,  7 
Aneurismal  varix,  7 
Angioma  of  ear,  85 

of  lips,  104 
Angle,  cardiohepatic,  205 

of  Ludwig,  180 
Ankle,  553 

amputation  of,  559 
Pirogoff's,  560 
Syme's,  559 
ankle-joint,  554 

distention  of,  555 
ligaments  of,  554 
movements  of,  554 
dislocations  of,  556 
treatment,  557 
excision  of,  555 
fractures  of,  557 

Pott's  fracture  by  aversion,  557 
by  inversion,  558 
sprain  of,  556 

treatment,  556 
surface  anatomy  of,  553 
tuberculosis  of,  555 
Annular  ligament, 

of  wrist,  anterior,  335 
posterior,  336 
Anterior  poliomyelitis,  487 
Antrum,  mastoid,  90 

operations,  91 
of  Highmore  (see  Maxillary  sinus) 
Anus  (see  Intestine,  large) 
Aorta,  208 

arch  of,  208 

aneurism  of,  210 
ductus  arteriosus,  209 
ascending,  208  ;  aneurism  of,  208 
bifurcation  of,  374 
descending,  210;  aneurism  of,  210 
Aponeurosis,  occipital,  2,  48 

pharyngeal,  116 
Apoplexy,  30,  31 

cortical,  32 
Appendicitis,  414 

operation  for,  414 
Appendicular  artery,  412 

Appendix  vermiformis   (see   Intestine,  large) 
Arachnoid,  21 

Aran's  law  for  fractures  of  the  skull,  15 
Arch:  of  aorta,  208 
femorosacral,  490 
of  foot,  561,  563 
external,  563 
internal,  563 
lateral  or  transverse,  563 
ligaments  of,  566 


Arch  of  foot,  muscles  supporting,  568 
ischiosacral,  491 
palmar,  deep,  359 

superficial,  358 
plantar,  572 
Arm,  266 

amputation  of,  275 
brachial  artery,  272 
humerus,  267 

fractures  of,  276 
intermuscular  septa  of,  271 
muscles  of,  267 
operations  on,  279 
surface  anatomy  of,  271 
Arterial  varix,  7 
Arteriovenous  aneurism,  7 
Artery  or  arteries, 

acromiothoracic,  258 
alarthoracic,  260 
alveolar,  inf.,  50 
anastomotica. magna,  274 
anterolateral  perforating,  28 
aorta,  208 
appendicular,  412 
arteria  centralis  retinae,  80 
artery  to  bulb,  475 
auricular,  deep,  50 

posterior,  3,  135 
axillary,  257 
basilar,  25 
brachial,  272,  290 
buccal,  50 
carotid,  common,  141 

external,  144 

internal,  25,  27,  143 
carpal,  anterior,  316 
cerebral,  anterior,  25,  27 

middle,  28 

posterior,  25,  28 
choroid,  anterior,  28 
circle  of  Willis,  25 
circumflex,  anterior,  261 

external,  523 

internal,  523 

posterior,  261 

superficial  external,  523 
coeliac  axis,  position  of,  374 
colic,  412 
communicating,  anterior,  25 

posterior,  25 
coronary,  inferior,  of  facial,  lot^ 

superior,  of  facial,  104 

of  stomach,  403 
of  corpus  cavemosum,  475 
cystic,  421 
deferential,  469 
dental,  50 

posterior,  50,  58 
dorsal,  of  penis,  475 
dorsalis  indicis,  360 

linguae,  no 

pedis,  572 

scapulae,  261 
epigastric,  deep,  379 

superficial,  523 

superior,  181,  379 
wounds  of,  379 
ethmoidal,  anterior,  98 

posterior,  98 
facial,  50,  134 
femoral,  523 
frontal,  3 
gastric,  403 


INDEX. 


603 


Artery,  gastroduodenal,  403 

gastro-epiploic,  dextra,  403 
gluteal,  505 

ligation  of,  505 
hemorrhoidal,  inferior,  440,  476 
middle,  440,  476 
superior,  440 
hepatic,  403,  421 
hyoid,  no 

hypogastric,  obliterated,  307,  371,  382 
ileal,  412 
ileocaecal,  anterior,  412 

posterior,  412 
ileocolic,  412 
iliac,  436 
iliac,  deep  circumflex,  379 

wounds  of,  in  operating  on  the  ap- 
pendix, 3S0 
line  of,  374 
infra-orbital,  50,  58 
intercostal,  176 
anterior,  176 
posterior,  177 
superior,  147 
labial,  inferior,  104 
lachrymal,  3 
lenticulostriate,  28 
lingual,  iio,  134.  145 
mammary,  internal,  147,  181 
masseteric,  50 
maxillary,  internal,  50,  58 
meningeal,  middle,  17,  21,  50 

small,  50 
musculophrenic,  181 
nasopalatine,  50,  58,  98 
occipital,  3,  4,  134 
ophthalmic,  3,  81 
ovarian,  458 
palatine,  ascending,  98 

descending,  50,  58,  98,  114 
palmar  arch,  deep,  359 

superficial,  358 
pancreatico-duodenal,  superior,  403 
perforating,  of  profunda  femoris,  5  23 
perineal,  superficial,  476 
transverse,  474,  476 
peroneal,  550 

ligation  of,  550 
pharyngeal,  ascending,  114.  i34 
plantar,  external,  572 
internal,  572 
ligation  of,  573 
popliteal,  544 
posterolateral,  29 
posteromedian,  28 
princeps  poUicis,  360 
profunda,  femoris,  522 
inferior,  274 
(superior),  274 
pterygoid,  50 

pterygopalatine,  50,  58,  98 
pudic,  deep  external,  523 
internal,  440,  474,  476 
superficial  external,  523 
pyloric,  403 
radial,  316,  359 
carpal,  316 
recurrent,  316 
radialis  indicis,  360 
ranine,  no 
renal,  426 
sacral,  middle,  441 
sciatic,  505 


Artery,  septal,  98,  104 
spermatic,  385,  469 
sphenopalatine,  50,  38,  98 
spinal,  anterior,  485 

posterior,  485 
splenic,  403 
subclavian,  139,  147 
sublingual,  no 
subscapular,  260 
superficial  volar,  316 
superior  ulnar  collateral,  274 
supra-orbital,  3 
suprascapular,  139 
temporal,  3,  48,  52 
deep  anterior,  50 
posterior,  50 
thoracic,  long,  260 

superior,  258 
thyroid  axis,  147 
thyroidea  ima,  165 
thyroid,  inferior,  149,  165 

superior,  134 
tibial,  anterior,  548 

posterior,  549 
tonsillar,  of  dorsalis  linguae,  1 14 

of  facial,  114 
transverse  cervical,  139 
tympanic,  50 
ulnar,  314,  358 

collateral,  inferior,  274 

superior,  274 
recurrent,  anterior,  315 
posterior,  315 
umbilical,  371,  382 
uterine,  458 
vasa  brevia,  403 
of  the  vas  deferens,  385 
vertebral,  25,  147 
vesicle,  superior,  371 
Vidian,  50,  58,  98 
Arthritic  muscular  atrophy,  488 
Articulations  (see  Joints) 
Arytenoid  cartilages,  129 
Ascites,  420 
Asterion,  39 
Attic  of  middle  ear,  88 

tegmen  of,  89 

perforation  of,  by  pus,  89 
Auditory  area  of  brain,  37 
nerve,  20 

injury  to,  in  fractures  of  skull,  20 
Auriculotemporal  branch  of  fifth  nerve,  3,  52 
Axilla,  229,  256 

abscess  of,  264 

incision  for,  264 
axillary  fascia,  256 
lymphatics  of,  263 
nerves  of,  265 
tumors  of,  265 
vessels  of,  257 
Axillary  artery,  257 

collateral  circulation  after  ligation  of,  262 
first  portion,  258 

ligation  of,  259 
second  portion,  260 
third  portion,  260 
ligation  of,  262 
Axillary  nerve,  265 

Back,  477 

surface  anatomy  of,  477 
Balance,  494 

disturbance  of,  494 


6o4 


INDEX. 


Balance,  methods  of  restoring,  494 
Bartholin,  duct  of,  108 
Basal  ganglia  of  brain,  37 

functions  of,  37 
Bassini's  operation  for  hernia,  387 
Battle's  abdominal  incision,  382 
Biceps  muscle,  269,  285,  310 
tendon  of,  255 

.  dislocation  of,  269 
rupture  of,  270 
Bicipital  fascia,  285 
groove,  221,  267 
tubercle,  285 
Bigelow,  Y  ligament  of,  507 
Bladder,  444 

attachments  of,  445 

base  of,  446 

cystoscopic  examination,  448 

extrophy  of,  454 

in  female,  447  ;  calculi  in,  447 

vesico- vaginal  fistulse  of,  447 
hypertrophy  of,  447 
interureteric  ligament  of,  446 
ligaments  of,  445 
operations  on,  448 
peritoneum  of,  445 
plicae  uretericae  or  ureteric  folds,  446 
position  of,  374,  444 

of  internal  urethral  orifice,  447 
postprostatic  pouch  or  bas-fond,  446 
rectovesical  pouch,  446 
ribbed,  447 
rupture  of,  446 
sacculated,  447 
shape  of,  445 
tapping  of.  446,  448 

Trendelenburg  position  in  operation  on,  446 
trigone  of,  446 
tumors  of,  448 
walls  of,  446 
Bloodgbod's  operation  for  hernia,  389 
Boeckman's  operation  on  the  hip,  518 
Bone  or  bones: 

astragalus,  or  talus,  562 
of  base  of  skull,  8 
carpal,  348 
of  chest,  171 
clavicle,  219 
coccyx,  432,  434 
of  cranium,  8 
cuboid,  562 

cuneiform,  of  tarsus,  562 
external,  562 
internal,  562 
middle,  562 
of  wrist,  332,  349 
of  elbow,  280 
ethmoid,  8 
of  face,  8,  44 
femur,  502 
fibula,  534,  571 

external  malleolus  of,  571 
fracture  of,  551 
frontal,  8 

external  angular  process  of,  40 
internal  angular  process  of,  46 
of  hand,  349 

carpal  bones,  349 
metacarpal  bones,  350 
phalanges,  351 
humerus,  221,  267,  280 
ilium,  499 

ala  of,  500 


Bones:  ilium,  anterior  superior  spine  of,  500,  go.4. 
crest  of,  499,  504 

posterior  superior  spine  of,  500,  504 
innominate,  432,  434,  499 

planes  of,  502 
ischium,  434,  500 

tuberosity  of,  500 

bursa  covering,  506 
lachrymal,  8,  44 
malar,  8,  44,  49 

fracture  of,  49 
maxilla,  inferior,  8,  44 

fracture  of,  67 
maxilla,  superior,  8,  44 
fracture  of,  54 
metacarpal,  350 

dislocations  of,  362 
metatarsal,  562 
nasal,  8,  44,  94 
occipital,  8 
OS  calcis,  562 

sustentaculum  of,  571 
tubercles  of,  571 
OS  magnum,  300 
palate,  8,  44 
parietal,  8 
patella,  534,  535 
phalanges  of  foot,  562 
of  hand,  351 

dislocation  of,  on  metacarpal  bones, 

262 
fracture  of,  364 
pisiform,  332,  349 
pubis,  434,  500 
crest  of,  501 
iliopectineal  line  of,  500 
ramus,  descending,  of,  501 

horizontal,  of,  501 
spine  of,  501 
radius,  281,  304 

lower  end  of,  331 
ribs,  174 
sacrum,  434 

scaphoid,  of  foot,  or  navicular,  562 
tubercle  of,  571 
of  wrist,  332,  349 
scapula,  219 
semilunar,  332,  349 
sphenoid,  8 
sternum,  174 
tarsal,  562 

fracture  of,  563 
temporal,  8 
tibia,  534 

fracture  of,  551 
internal  malleolus  of,  573 
trapezium,  350 
trapezoid,  350 

turbinated,  inferior,  8,  44,  97,  118 
hypertrophy  of,  118 
middle,  97,  118 
superior,  97 
ulna,  281,  303 

lower  end  of,  332 
unciform,  350 
vomer,  8,  44 
of  wrist,  330 
Bony  landmarks  of  foot,  570 

of  skull,  39 
Bovee's  operation  for  excision  of  ureter,  451 
Bow-legs,  543 

treatment,  544 
Brachial  artery,  272,  290 


INDEX. 


605 


Brachial  artery,  branches  of,  273 
ligation  of,  274 

collateral  circulation  after,   275 
ligation  of,  at  bend  of  elbow,  290 

collateral  circulation  after,   291 
plexus,  265 
Brachialis  anticus  muscle,  270,  286 
Brain,  25 

apoplexy,  30 

cortical,  32 
basal  ganglia,  blood  supply  of,  28 
blood   supply  of,  in  obstruction  to   circle   of 

Willis,  25  ' 
caudate  nucleus,  30,  31 

blood  supply  of,  28 
cerebral  abscess,  44 

lobes,  32 
cerebral  localization,  34 

functions  of  basal  ganglia,  37 

convolutions  on  surface  of  cerebrum, 

■  35 

corona  radiata,  38 
crura  cerebri,  38 
internal  capsule,  38 
motor  tract,  38 
pons  Varolii,  38 
cerebral  softening,  30 
choroid  plexus,  30 
circulation  of,  25 
convolutions  of,  33 

angular  gyrus,  33,  42 
Broca's  convolution,  33 
frontal  convolution,  33,  41 
gyrus  fomicatus,  34 
marginal  convolution,  34 
occipital  convolutions,  33,  42 
parietal  convolutions,  33 
supramarginal  gyrus,  33,  41 
temporal  convolutions,  ^;},  41 
corpus  striatum,  30,  31 
cortex,  blood  supply  of,  28 

functions  of,  34 
craniocerebral  topography,  39 
bony  landmarks,  39 
convolutions,  main,  40 

subsidiary,  41 
fissures  in  children,  42 
main,  39 
subsidiary,  41 
lower  level  of  brain,  40 
ventricles,  lateral,  43 
topographical  points,  40 
cms  cerebri,  31 
decussation,  motor,  31 
external  capsule,  31 
fissures  of,  i^^ 

calcarine,  34 
longitudinal,  33,  39 
parietooccipital,  ^;},  40 
cf  Rolando,  ;i3,  40 
of  Sylvius,  2^,  40 
transverse,  ^-^ 
foramen  lacerum  medium,  27 

Monro,  30 
fornix,  pillars  of,  30 
hemispheres,  lateral  surface  of,  33 

medial  surface  of,  34 
internal  capsule,  31 
lenticular  nucleus,  31 
lobes  of,  32 
lower  level  of,  40 
medulla,  31 
paralysis,  crossed,  32 


Brain,  perforated  space,  anterior,  28 
pons,  31 

hemorrhage  into,  32 
relations  of,  to  lateral  sinus,  93 
septum  lucidum,  30 
taenia  semicircularis,  30 
thalamus,  30,  31 
trephining,  44 
veins  of  Galen,  31 
velum  interpositum,  31 
venous  sinuses  of,  i  2 
ventricles,  30 

fifth  ventricle,  30 
lateral  ventricles,  30,  43 
third  ventricle,  30 
Breast  (see  Mammary  gland) 
Bregma,  39 
Broad  ligament,  455 

tumors  of,  462 
Broca's  convolution  of  brain,  35 

functions  of,  35 
Brunner,  glands  of,  406 
Bryant's  triangle,  505 
Buccopharyngeal  fascia,  153 
Bulla  ethmoidalis,  100 
Bunion,  579 
Bums,  ligament  of,  390 
Bursa  or  bursae: 

covering  tuberosity  of  ischium,  506 

disease  of,  506 
great  carpal,  366 
infraspinatus,  255 
of  knee,  538,  539 

mfrapatellar,  539 
posterior  bursae,  539 
prepatellar,  538 

inflammation  of,  538 
suprapatellar,  538 
of  olecranon,  300 

disease  of,  300 
of  shoulder,  255 
subacromial,  255 
subfemoral,  535 
subscapular,  255 

Caecal  folds,  413 

fossae,  413 
Caecum  (see  Intestine,  large) 
Calcaneus,  tendo  (see  Achilles') 
Canal, 

Alcock's,  474,  476 

femoral,  390 

Hunter's,  524 

inguinal  (see  Inguinal) 

lachrymal,  72,  84 

of  Schlemm,  79 
Canaliculi,  lachrymal,  84 
Cancer 

of  breast,  185 

operation  for,  187 

of  lips,  105 

treatment,  105 

of  oesophagus,  212 

of  stomach,  404 

adhesion  in,  405 
perforation  in,  405 
ulceration  in,  405 

of  tongue,  1 10 
Cancrum  oris,  49 
Capitellum,  280 
Capsule,  external,  31 

internal,  31 

of  kidney,  426 


6o6 


INDEX. 


Capsule  of    parotid,    submaxillary    and    thyroid 
glands,  15,^ 
of  prostate  gland,  449 
Tenon's,  74 
of  Tonsil,  114,  116 
Caput  medusae,  380 
succedaneum,  5 
Carcinoma  (see  Cancer) 
Cardiohepatic  angle,  205 
Caries  of  the  spine,  480 
Carotid  artery,  common,  141 

collateral  circulation  after    ligation 

of,  142 
in  superior  carotid  triangle,  133 
ligation  of,  141 

hgation  of,  below  omohyoid  muscle, 
142 
external,  144 

in  superior  carotid  triangle,  133 
ligation  of,  144 
internal,  25,  27,  143 

in  cavernous  sinus,  14 
in  superior  carotid  triangle,  133 
ligation  of,  143 
relations  of,  to  pharynx,   123 
relations  of,  to  tonsil,  123 
tubercle,  149 
Carpal  bursa,  great,  366 
Carpometacarpal  joints, 

movements  of,  353 
Carrying  angle,  282 
Cartilage  or  cartilages: 
arytenoid,  124 
cricoid,  126 
of  Santorini,  124 
of  septum,  97 
tarsal,  82 
thyroid,  125 

fracture  of,  125 
of  Wrisberg,  1 24 
Castration,  469 
Cataract,  78 

operations  for,  79 
varieties  of:  capsular,  78 
lamellar,  78 
lenticular,  78 
lenticulocapsular,  78 
polar,  78 
secondary,  78 
senile,  78 
traumatic,  78 
zonular,  78 
Catheter,  passage  of,  471 
Caudate  nucleus,  30,  31 

blood  supply  of,  28 
Cavernous  sinus,  13 
Cells,  ethmoid,  73,  102 
disease  of,  102 
mastoid,  1 1,  90 

operation  on,  91 
Central  lobe  of  brain,  33 
Cephalhaematoma,  5 
Cephalhydrocele,  7 
Cerebellar  abscess,  13 
Cerebral  abscess,  44 
Cerebral  lobes,  32 

central,  or  island  of  Reil,  33 
frontal,  37 
occipital,  32 
parietal,  32 

temporosphenoidal,  32 
localization  (see  Brain) 
softening,  30 


Cerebral  venous  sinuses,  1 2 

cavernous  sinus,  13 
lateral  or  transverse  sinus,  1 2 
superior  longitudinal  sinus,  12 
torcular  Herophili,  12 
Cerebritis,  23 
Cerebrospinal  fluid  in  fractures  of  skull,  19 

meningitis,  25 
Cervical  adenitis,  158 

operation  for,  158 
cysts,  169 
fascias,  150 

influence  of,  on  pus  in  neck,  154 
fistulae,  168 
triangles,  131 

anterior,  131 

inferior  carotid,  131,  137 
submaxillary,  131 
superior  carotid,  131,  133 
posterior,  137 

occipital,  137 
subclavian,  131,  137 
Chalazion,  83 
Cheek,  49 

contusions  of,  49 
wounds  of,  49 
Chest,  171,  192 
bones  of,  171 
ribs,  174 
sternum,  174 
costal  cartilages,  174 
heart,  204 
lines  of,  192 
lungs,  196 

mammary  gland,  182 
mediastinum,  187 
muscles  of,  177 
cesophagus,  211 
paracentesis  of,  200 
pericardium,  201 
pleurae,  194 
regions  of,  192 
shape  of,  171 
soft  parts,  176 
surface  anatomy  of,  180 
vertebrae  of,  176 
walls  of,  171 
Chiene's  method  of  finding  the  fissure  of  Rolanao 

42 
Choked  disk,  80 
Chopart's  amputation,  574 
Chordee,  466 
Choroid  coat  of  eye,  77 

afTections  of,  77 
plexus,  30 
Circle  of  Willis,  25 
Circulation  of  the  brain,  25 
Circumcision,  466 
Circumflex  iliac  artery,  deep,  379 

wound   of,  in  operating    on  ap* 
pendix,  380 
nerve,  265 
Cirsoid  aneurism,  7 
Clavicle,  219 

dislocations  of,  230 
acromial  end,  231 
sternal  end,  230 
excision  of,  250 
fractures  of,  241 

inner  third,  241 
middle  third,  241 
outer  third,  241 
Clavipectoral  fascia,  256 


INDEX. 


607 


Cleft  palate,  iir 

operation  on,  112 
Clitoris,  462 
Cloaca,  453 
Coccygodynia,  439 
Coeliac  axis,  403 

position  of,  374 
Colles's  fascia,  377 

fracture,  342 

reduction  of,  343 
Colon  (see  Intestine,  large) 
Colostomy,  417 

inguinal,  417 
Columns  of  Morgagni  or  Glisson,  440 
Combined  posterolateral  sclerosis,  488 
Common  bile-duct,  421 
Complemental  space  of  Gerhardt,  194 
Compound  ganglion,  342 
Condyle  of  lower  jaw,  64 

excision  of,  71 
Condyles  of  humerus,  280 
Congenital  dislocation  of  hips,  514 

hernia,  383 

hydrocele,  384 
Conjoined  tendon,  376 
Conjunctiva,  82,  83 

bulbar,  83 

fornix  of,  83 

palpebral,  83 
Conoid  ligament,  222,  257 
Contusions  of  cheek,  49 

of  scalp,  5 
Convolutions  of  brain,  33 

in  craniocerebral  topography,  40,  41,  42 
Coraco-acromial  ligament,  222 
Coracohumeral  ligament,  194 
Corona  radiata,  38 

functions  of,  38 
Coronary  ligament  of  liver,  397,  418 
Coronoid  fossa,  280 
Corpora  quadrigemina,  38 

blood  supply  of,  29 
Corpus  striatum,  30,  31 

functions  of,  37 
Costocoracoid  ligament,  257 

membrane,  257 
Costomediastinal  sinus,  194 
Costophrenic  sinus,  194 
Cowper's  gland,  471,  474 
Coxalgia  or  coxitis,  515 

abscess  in,  516 

attitude,  516 

measurements,  516 

symptoms,  515 
Coxa  valga,  517 

vara,  517 
Craniocerebral  topography  (see  Brain) 
Cranium,  8 

Vjones  of,  8 
Cremaster  muscle,  377 
Crest,  infratemporal,  47 
Cribriform  fascia,  391 
Cricoid  cartilage,  126 
Cricothyroid  membrane,  125 
Cms  cerebri,  31 

blood  supply  of,  29 
functions  of,  38 
Crutch  palsy,  265 
Crypts  of  Morgagni,  440 
Cubitus  varus,  297 
Cuneiform  bone 

of  carpus,  349 
of  tarsus,  562 


Cuneus  lobe  of  brain,  34 

Cushing's  operation  on  the  Gasserian  ganglion,  60 

Cut  throat,  168 

Cyclitis,  77 

Cystic  duct,  421 

Cystocele,  435,  464 

Cystotomy,  448 

Cysts  of  neck,  169 

median,  170 
of  salivary  glands,  108 
treatment,  109 

Davis:    method  of  amputation  of  penis,  466 

method  of  reduction  of  congenital  dislocation 

of  hips,  515 
transverse  incision  for  appendicitis,  414 
Decussation,  motor,  31 
Deltoid  ligament  of  ankle,  554,  565 

muscle,  268 
Dental  nerve,  inferior,  excision  of,  60 
Dermoid  tumor  of  scalp,  8 
Development  of  urogenital  system,  553 
Diaphragm,  hiatus  in,  425 

relation  of,  to  pus  in  kidney  region,  425 
Diploe  of  skull,  10,  15 
Dislocation  of  ankle,  556 
treatment,  557 
of  bases  of  metacarpal  bones,  362 
of  clavicle,  230 

acromial  end,  231 
sternal  end,  230 
of  elbow,  291 

backward,  291 

treatment,  292 
inward,  293 

treatment,  294 
outward,  294 

treatment,  295 
of  fingers,  363 
of  head  of  radius,  294 
of  hip  (see  Hip) 
of  jaw,  lower,  66 

reduction  of,  67 
of  knee,  541 

of  nose,  treatment  of,  96 
of  patella,  540 

treatment  of,  541 
of  phalanges  on  metacarpal  bones,  362 
of  shoulder,  232 
anterior,  232 

method  of  production  of,  233 
parts  injured,  233 
reduction  of,  236 

direct  method,  236 
indirect  method,  238 
signs  and  symptoms  of,  235 
posterior,  239 
of  spine,  481 
of  toes,  580 

of  big  toe,  580 
of  wrist,  345 

at  radio-carpal  joint,  345 
at  radio-ulnar  joint,  345 
Douglas's  p)ouch,  398,  454 
Douglas,  semilunar  folds  of,  376 
Duct  or  ducts: 

of  Bartholin,  108 
common  bile-duct,  421 
stone  in,  422 

operation  for,  422 
cystic,  421 

stone  in,  422 

operation  for,  422 


6o8 


INDEX. 


Duct,  ejaculatory,  471 

of  Gartner,  454 

hepatic,  421 

stone  in,  422 

operation  for,  422 

lachrymonasal,  72,  84,  99 

lymphatic,  right,  140 

of  Mtiller,  453 

pancreatic,  423 

para-urethral,  463 

parotid,  51 

calculus  in,  51 

of  Rathke,  454 

of  Rivinus  (see  Bartholin) 

of  Santorini,  423 

Stenson's,  51 

thoracic,  140,  214 
wounds  of,  214 

thyroglossal,  107 

in  fistulae  of  neck,  170 

vitelline,  371,  382 

of  Walther,  108 

Wharton's,  108 

of  Wirsung,  423 
Ductus  arteriosus,  209 
Duodenojejunal  flexure,  408 

fossae,  408 
Duodenum  (see  Intestine,  small) 
Dupuytren's  splint  in  fracture  of  ankle,  557 
Dural  hemorrhage, 

of  brain,  23 

of  cord,  486 
Dura  mater,  20 

in  children,  9 

Ear,  84 

Eustachian  catheter,  120 

tube,  84,  89,  118 
external,  84 

affections  of,  85 
angioma  of,  85 
haematoma  of,  85 
meatus,  external  auditory,  84,  85 

fissures  of  Santorini,  86 
furuncles  of,  86 
nerves  of,  87 
wax  in,  86 
membrana  tympani,  87 

paracentesis  of,  88 
perforation  of,  87,  88 
middle,  88 

aditus,  88 
antrum,  90 

operations  on,  91 
aqueduct  of  Fallopius,  89 
attic,  88,  89 
disease  of,  90 
fenestra  ovale,  89 
fenestra  rotundum,  89 
mastoid  cells,  90 

operation  on,  91 
operations  on,  90 
walls  of,  88 
suprameatal  fossa,  91 
spine,  91 

triangle  of  Macewen,  91 
■iympanum  (see  Ear,  middle) 
Ear-wax,  86 

Edebohls's  incision,  382,  396 
Ejaculatory  ducts,  471 
Elbow,  280 

amputation  at,  302 
bones  of,  280 


Elbow,  bones  of,  epiphyses  of,  299 
brachial  artery,  290 

ligation  of,  at  elbow,  290 
carrying  angle,  282 
dislocations  of,  291 
backward,  291 

treatment,  292 
of  head  of  radius,  295 

treatment,  295 
inward,  293 

treatment,  294 
outward,  294 

treatment,  294 
elbow-joint,  282 
disease  of,  300 
ligaments  of,  283 
fractures  in  the  region  of,  295 
muscles  of,  284 
olecranon  bursa,  300 

disease  of,  300 
radio-ulnar  articulation,   superior,   283 

ligaments  of,  283 
resection  of,  301 
surface  anatomy,  287 
veins  of,  288 
Eminence,  frontal,  8,  45 
hypothenar,  353 
thenar,  353 
Emphysema  of  orbit,  76 
Empyema,  200 

operation  for,  200 
resection  of  rib  for,  201 
Encephalitis,  23 
Encephalocele,  7 
Epididymis,  468 

epididymitis,  469 
Epidural  hemorrhage,  17 
Epigastric  artery,  deep,  379 
position  of,  374 
relations    to    Hesselbach's    triangle, 

387 
to  inguinal  hernia,  379,  387 
to  internal  ring,  386 
wounds  of,  379 
superior,  379 

wounds  of,  379 
region  of  abdomen,  370 
Epiglottis,  124 

Epiphyseal  separations  of  acromium,   247 
of  coracoid  process,  247 
of  elbow,  299 

of  humerus,  upper  end,  247 
of  knee,  541 

of  radius,  lower  end,  344 
Epistaxis,  98 

Epithelioma  of  lips  (see  Cancer) 
Equilibrium,  anteroposterior,  492 

effect  of  ankylosis  of  hip-joint  on,  493 
effect  of  spinal  deformities  on,  493 
lateral,  494 

deviations  of  spine  above  sacrum,  495 
Erector  spinas  muscle,  392 
Ethmoid  bone,  8 

cells  or  sinus  (see  Sinus) 
Eustachian  catheter,  120 
tube,  84,  89,  118 

catheterization  of.  120 
inflammation  of,  8g,  119 
methods  of  inflating,  S9,  119 
Excision  (see  Resection) 
Extensor  carpi  radialis  brevior,  286 

longior,  286 
External  oblique  muscle,  377 


INDEX. 


609 


Extradural  hemorrhage  of  brain,  17 

of  cord,  486 
Extra-uterine  pregnancy,  462 
Extravasation  of  blood  into  perineum,  475 
of  urine  into  penis,  466 
of  urine  into  perineum,  475 
Extremity,  lower,  489 
ankle,  553 

attachment  of,  to  trunk,  491 
balance,  494 
distortions   resulting  from   affections  of, 

496 
equilibrium,  anteroposterior,  492 

lateral,  494 
foot,  561 

general  considerations  of,  489 
hip,  499 
knee.  533 

leg,  S4S  . 

lengthening  of,  497 

measurement  of  lower  limbs,  497 

pelvis,  490 

shortening  of,  497 

thigh,  519 

walking,  498 
upper,  216 

functions  of,  216 

morphology  of,  216 

shoulder,  217 
Eye,  72 

anterior  chamber,  79 

anterior  lymph  circulation  of,  79 

aqueous  humor,  77,  79 

canthus  of,  82 

cataract  (see  Cataract) 

choked  disk,  80 

choroid,  77 

choroiditis,  77 
ciliary  body,  7  7 
conjunctiva,  83 
cornea,  77 
cyclitis,  77 
eyeball,  72,  77 
glaucoma,  79 
hyaloid  membrane,  77 

iris,  77.  79 

aiTections  of,  79 
keratitis,  77 

lachrymal  apparatus,  83 
lens,  77 
lids,  72 

ligament  of  Zinn,  81 
macula  lutea,  77 
muscles  of, 

ciliary,  77 

dilator  pupilte,  79 

oblique,  inferior,  81 
superior,  81 

rectus,  external,  81 
inferior,  81 
internal,  81 
superior,  81 

sphincter  pupillae,  79 
optic  disk,  80 
optic  nerve,  79 

optic  neuritis,  80 
orbits  (see  Orbit) 
posterior  chamber,  79 
retina,  77 

detachment  of,  77 

retinitis,  77 
sclerotic  coat,  77 
spaces  of  Fontana,  79 

39 


Eye,  staphyloma,  anterior,  77 
posterior,  77 

synechia  anterior,  79 
posterior,  79 

vitreous  humor,  77 

zone  of  Zinn,  77 
Eyelids,  82 

chalazion,  83 

eyelashes,  83 

layers  of,  82 

Meibomian  glai:ds,  82 

stye,  83 

tarsal  plates,  82 

Face,  44 

blood-vessels  of,  44 
bones  of,  8,  44 
facial  artery,  50 
frontal  region  of,  45 
infra-orbital  nerve,  56 

removal  of,  56 
internal  maxillary  artery,  50 
jaw,  lower,  63 
jaw  upper,  54 

fractures  of,  54 
resection  of,  55 
maxillary  nerve,  56 

neuralgia  of,  55 
nerves  of,  44 
region  of  cheek,  49 
region  of  eye,  72 
removal  of  Meckel's  ganglion,  57 
soft  parts,  44 

blood-vessels,  44 
nerves,  44 
temporal  region,  46 
Facial  artery,  50,  134 
nerve,  20,  52 

injury  to,  in  fracture  of  skull,  20 
paralysis  of,  82 
Falciform  process,  390 
Fallopian  tubes,  456 

development  of,  453 
operation  on,  460,  461 
Falx  cerebri,  20 
Fascia,  anal,  435 
axillary,  256 
bicipital,  285 
buccopharyngeal,  153 
Buck's,  465 
clavipectoral,  178,  256 
CoUes's,  473 
cribriform,  391 
deep,  of  forearm,  329 

pus  beneath,  329 
intercolumnar,  377 
lata,  377 
of  leg,  548 
lumbar,  393 

anterior  layer  of,  393 
•    middle  layer  of,  393 
posterior  layer  of,  393 
of  neck,  150 

influence  of,  on  pus  in  neck,  154 
layers  of,  deep,  151 
superficial,  150 
obturator,  435 
palmar,  357 

abscess  beneath,  365 
parotid,  52 
pectoral,  178 
pelvic,  435 
perineal,  473 


6io 


INDEX. 


Fascia,  perirenal,  426 
plantar,  567 

abscess  beneath,  575 
pretracheal,  153 

pus  above,  154 
pus  beneath,  155 
prevertebral,  153 

pus  in  front  of,  155 
pus  posterior  to,  155 
rectovesical,  435,  436 
Scarpa's,  374 

superficial,  of  abdomen,  374 
temporal,  47 
transversalis,  399 
triangular,  377 
of  wrist,  deep,  335 
Fascial  triangle,  394 
Fat,  subperitoneal,  399 
Fauces,  pillars  of,  112 
Felon,  367 
Femoral  artery,  523 

collateral  circulation  after  ligation  of,  525 
in  Hunter's  canal,  525 
ligation  of,  in  Hunter's  canal,  525 
in  Scarpa's  triangle,  523 
canal,  390 
sheath,  390 
Femorosacral  arch,  490 
Femur,  502 

coxa  valga,  502 
coxa  vara,  502 
fractures  of,  529 
neck,  529 
shaft,  531 
trohcanters,  531 
osteotomy  of,  544 
Fibula,  534,  571 

fracture  of,  551 
Fifth  nerve  (see  Trifacial) 
Fingers,  amputations  of,  369 

metacarpophalangeal,  369 
dislocations  of  distal  and   middle  phalanges, 

363 
phalanges  on  metacarpal  bones,  362 
suppuration  involving,  366 
Fissure  or  fissures,  anal,  443 
of  brain,  3;^ 

calcarine,  34 
longitudinal,  33 
parieto-occipital,  33 
of  Rolando,  33 
of  Sylvius,  33 
transverse,  33 
of  liver,  418 
orbital,  inferior,  74 

superior,  74 
of  Santorini,  86 
sphenoidal,  74 
sphenomaxillary,  74 
Fistula  in  ano,  443 
Fistulas  of  neck,  169,  170 
median,  170 
urinary,  382 
vesicovaginal,  447 
Flat-foot,  577 

treatment,  578 
Floating  kidney,  427 
Fontana,  spaces  of,  79 
Fontanelles,  8 
anterior,  8 
anterolateral,  9 
posterior,  8 
posterolateral,  9 


Foot,  561 

amputations  of,  574 

midtarsal  (Chopart's),  574 
tarsometatarsal  (Lisfranc's),  575 
arch  of,  561,  563 

external  arch,  563 
internal  arch,  563 
lateral  or  transverse  arch,  563 
ligaments  of,  566 
muscles  supporting,  568 
arteries  of,  572 
bones  of,  562 
construction  of,  561 
deformities  of,  576 
flat-foot,  577 
hallux  valgus,  579 
pronation  of,  577 
talipes  calcaneus,  578 
cavus,  578 
valgus,  577 
varus,  576 
diseases  and  injuries  of,  561 

treatment  of,  562 
joints  of,  569 

midtarsal  or  Chopart's,  566 
subastragaloid,  564 
ligaments  of,  565 
sprain  of,  566 
ligaments  of,  564 
metatarsalgia,  580 
muscles  of,  568 

action  of,  as  abductors  and  adductors,  570 
action  of,  as  flexors  and  extensors,  569 
action  of,  in  supporting  tarsal  arch,  568 
plantar  abscess,  575 
deep,  575 
superficial,  575 

incision  for,  575 
plantar  fascia,  567 

abscess  beneath,  575 
surface  anatomy  of,  570 

bony  landmarks,  570 
joints,  572 
tendons,  571 
toes,  579 

amputation  of,  581 
dislocations  of,  580 
hammertoe,  579 
ingrown  nail,  579 
metatarsalgia,  580 

resection    of    metatarsophalangeal    joint, 
580 
Foramen  of  Key,  22 
of  Magendie,  22 
mental,  63 
of  Monro,  31 
nasopalatine,  1 1 1 
obturator,  434,  501 
optic,  74 
ovale,  60 

palatine,  posterior,  112 
of  Retzius,  22 
rotundum,  60 
sacrosciatic,  greater,  434 
lesser,  434 

structures  passing  through,  434 
of  Winslow,  398 
Foramina  of  Scarpa,  1 1 1 

of  Stenson,  98,  i  n 
Forearm,  303 

amputation  of,  326 

through  lower  third,  327 
through  middle  third,  327 


INDEX. 


6ii 


Forearm,  amputation  of,  through  upper  third,  327 
arteries  of,  314 
bones  of,  303 
deep  fascia  of,  329 

pus  beneath,  329 
fractures  of,  321 

both  bones,  321 

treatment,  322 
shaft  of  radius,  322 

treatment,  324 
shaft  of  ulna,  325 

treatment,  325,  326 
movements  of  pronation  and  supination,  304 
muscles  of,  305 

extensors  and  flexors  of  fingers,  306 
extensors  and  flexors  of  wrist,  308 
pronators  and  supinators  of  hand,  310 
nerves  of,  317 

operations  on  bones  and  other  structures,  328 
surface  anatomy  of,  312 

anterior  surface,  312 
posterior  surface,  314 
Foreign  bodies: 

in  larynx,  125 
in  orbit,  76 
in  pharynx,  1 24 
Fornix,  pillars  of,  30 
Fossa  or  fossae: 
caecal,  413 

ileocaecal  fossa,  inferior,  414 

superior,  413 
retrocolic  fossae,  414 
duodenojejunal,  inferior,  408 

superior,  408 
epigastric,  180 
inguinal, 

external,  387 
internal,  387 
middle,  387 
intersigmoid,  417 
of  Rosenmiiller,  123 
suprameatal,  91 
supratonsillar,  113 
Fourchette,  462 
Fracture 

of  alveolar  process  of  upper  jaw,  54 
of  both  bones  of  forearm,  321 

treatment,  322 
of  clavicle,  241 

inner  third,  241 
middle  third,  241 
outer  third,  243 
Colles's,  342 

reduction  of,  343 
of  coronoid  process  and  upper  end  of  radius, 

299 
of  femur,  529 
neck,  529 

impaction  in,  530 
treatment,  531 
shaft,  531 

treatment,  531 
trochanters,  531 
treatment,  531 
of  humerus 

above  the  condyles,  295 
treatment,  295 
intercondylar  or  T  fracture,  298 
involving  the  condyles,  296 
extra- articular.  296 
intra-articular,  297 
shaft,  276 

above  insertion  of  deltoid,  277 


Fracture  of  humerus,  shaft,  below  insertion  of  del- 
toid, 277 
injury  to  radial  nerve  in,  277 
non-union  in,  277 
treatment,  277 
upper  end,  244 

anatomical  neck,  244 
surgical  neck,  245 
through  the  tuberosities,  245 
treatment,  246 
of  jaw,  lower,  67 

displacement,  69 
treatment,  70 
upper,  54 
of  malar  bone,  49 
of  maxilla,  inferior  (see  Jaw) 

of  maxilla,  sviperior  (see  Jaw) 
of  metacarpal  bones,  364 
of  nose,  95 

treatment,  96 
of  olecranon,  298 

treatment,  298 
of  patella,  539 

by  direct  violence,  540 
by  indirect  violence,  539 
treatment  of,  540 
of  pelvis,  491 
of  phalanges,  363 
Pott's,  by  e version,  557 
by  inversion,  558 
treatment,  558 
of  radius,  Colles's,  342 

coronoid  process,  299 

head  and  neck,  299 

lower  end  with  forward  displacement,  344 

shaft,  322 

above  pronator  radii  teres,  323 
below  pronator  radii  teres,  323 
treatment,  324 
of  ribs,  175 

of  scapula,  acromion  process,  244 
body,  244 

coracoid  process,  244 
glenoid  process,  244 
surgical  neck,  244 
of  skull,  15 

Aran's  law  in,  15 
in  adults,  15 

bleeding  from  sinuses  in,  19 
cerebrospinal  fluid  in,  19 
in  childhood,  14 
by  contrecoup,  16 
emphysema,  in  19 
hemorrhage  in,  16 
injuries  to  nerves  in,  19 
through  anterior  cerebral  fossa,  16 
through  middle  cerebral  fossa,  17 
through  posterior  cerebral  fossa,  17 
trephining  for  middle  meningeal  hemor- 
rhage in,  18 
trephining  for  posterior  branch  of  middle 
meningeal  artery  in,  18 
of  spine,  482 
of  sternum,  174 
of  tarsal  bones,  563 
of  thyroid  cartilage,  125 
of  tibia,  551 

action  of  tendo  calcaneus  in,  551 
treatment,  551 
of  ulna,  lower  end,  344 
olecranon,  298 

treatment,  298 
shaft,  325 


6l2 


INDEX. 


Fracture  of  ulna,  shaft,  below  middle,  325    , 
treatment,  325 
upper  third,  326 
treatment,  327 
Friedreich's  ataxia,  488 
Frontal  bone,  8 

convolutions  of  brain,  33 
eminences,  45 
lobe  of  brain,  32 

blood  supply  of,  28 
process,  external,  40 

internal,  46 
region,  45 
sinuses  (see  Sinus) 
suture,  45 
Funnel  chest,  172 

Galen,  veins  of,  31 
Gall-bladder,  372,  420 

common  bile-duct,  421 
cystic  duct,  421 
gall-stones,  422 

operation  for,  422 
position  of,  372,  399 
Gall-stones,  422 

operations  for,  422 
Ganglion,  compound,  of  wrist,  342 
Gasserian,  60 

operations  on,  60 
of  knee,  539 
Meckel's,  57 

removal  of,  57 
Gasserian  ganglion  (see  Ganglion) 
Gastrectomy,  405 
Gastric  artery,  403 
ulcer,  403 

perforation  of,  404 
Gastro-enterostomy,  406 
Gastroplication,  405 
Gastroptosis,  403 
Gastrotomy,  405 
Generative  organs,  female,  454 

blood-vessels  of,  458 
broad  ligament,  455 
development  of,  453 
external,  462 

clinical  considerations  of,  464 
Fallopian  tube,  456 
lymphatics  of,  458 
operations  on,  460 
ovary,  456 

pelvic  examination,  459 
perineum,  464 
uterus,  454 
vagina,  457 
male,  465 

development  of,  453 
penis,  465 
perineum,  472 
scrotum,  467 
spermatic  cord,  469 
testicle,  468 
urethra,  470 
Gerhardt,  complemental  space  of,  194 
Gerota,  perirenal  fascia  of,  427 
Gimberriat's  ligament,  377,  390 
Glabella,  39 
Gland  or  glands: 

Bartholin's,  463 
of  Brunner,  406 
Cowper's,  471 
Haversian,  507 
lachrymal,  72,  83 


Glands  of  Littr^,  471 

mammary,  182 

jneibomian,  82 

parotid,  3,  51 

capsule  of,  153 

prostate,  448 

sublingual,  108 

submaxillary,  132 
capsule  of,  153 

thymus,  188 

thyroid,   164 

vulvovaginal,  463 
Glaucoma,  79 

Glosso-epiglottic  folds,  108,  124 
Glossopharyngeal  nerve,  20 

injury  to,  in  fractures  of  skull,  20 
Gluteal  cleft,  505 

fold,  505 
Goitre,  1 28 

Goldthwait's  operation  for  dislocationof  patella,  541 
Groin,  lymphatics  of,  527 
excision  of,  527 
Gunstock  deformity,  297 
Gustatory  area  of  brain,  37 
Gyrus  fornicatus,  34 

Haematemesis,  420 
Hasmatoma  of  ear,  85 
neonatorum,  8 
of  scalp,  5 
HEematomyelia,  486 
Hallux  valgus,  579 

treatment,  579 
Hammer  toe,  579 
Hand,  349 

abscesses  of,  365 

beneath  palmar  fascia,  365 
involving  fingers,  366 
suppuration  in  tendon  sheaths,  366 
amputation  of  fingers,  369 

of  thumb,  368 
arteries  of,  358 
bones  of,  349 
dislocations  of,  362 

bases  of  metacarpal  bones,  362 
distal  and  middle  phalanges,  363 
phalanges  on  metacarpal  bones,  362 
proximal  phalanx  of  thumb,  362 
fractures  of,  364 

metacarpal  bones,  364 
phalanges,  364 
treatment,  364 
joints  of,  352 

movements  of,  353 
synovial  membrane  of,  352 
suppuration  of,  352 
lymphatics  of,  368 
muscles  of,  353 
nerves  of,  360 
palmar  fascia,  357 
surface  anatomy  of,  354 
wounds  of,  364 
Harelip,  105 

treatment,  106 
Harrison's  groove,  172 
Hartmann-Mikulicz  line,  406 
Heart,  204 

area  of  dulness  of,  205 

cardiohepatic  angle,  205 

dilatation  of.  as  cause  of  pleural  effusion,  191 

location  of  valvular  sounds  of,  206 

outlines  of,  204 

portion  uncovered  by  lung-tissue,  204 


i 


INDEX. 


613 


Heart,  valves  of,  206 

variation  in  size  and  position  of,  206 
wounds  of,  207 

operation  for,  207 
Hemianopia,  82 
binasal,  82 
bitemporal,  82 
homonymous,  82 
lateral,  82 
Hemispheres  of  brain, 

lateral  surface,  33 
medial  surface,  34 
Hemorrhage,  dural,  23 
epidural,  17 
middle  meningeal,  17 
into  orbit,  77 
pial,  23 

from  plantar  arteries,  573 
into  pons,  32 

from  sinuses  in  fracture  of  skull,  19 
into  spinal  cord,  486 
Hemorrhoidal  arteries,  440 
inferior,  440,  476 
middle,  440,  476 
superior,  440 
veins,  441 
Hemorrhoids,  420,  442 
external,  442 
'  internal,  442 
strawberry,  443 
treatment  of,  443 
Hepatic  artery,  403,  421 
duct,  421 

flexure  of  colon,  374 
Hereditary  spastic  paraplegia,  488 
Hernia,  382 

abdominal,  382 
congenital,  383 

descent  of  testis,  383 
encysted,  384 
funicular,  384 
infantile,  384 
umbilical,  382 
vaginal,  384 
femoral,  390 

coverings  of,  390 
radical  cure  of,  392 
saphenous  opening  in,  390 
strangulation  of,  392 
division  of,  392 
inguinal,  383 

acquired,  385 

direct,  385,  387 

coverings  of,  388 
Hesselbach's  triangle,  387 
radical  cure  of,  389 
strangulation  of,  388 
division  of,  388 
indirect,  385 

coverings  of,  386 
radical  cure  of,  387 
strangulation  of,  386 
division  of,  387 
lumbar,  394 
obturator,  435 
pelvic,  435 
perineal,  435 
retroperitoneal,  408 
sciatic,  435 
of  testicle,  469 
umbilical,  382 

acquired,  383 
infantile,  383 


Hernia,  umbilical,  infantile,  treatment,  383 

operation  on,  383 
Hesselbach's  triangle,  387 
Hiatus  semilunaris,  97,  100 
Hip,  499 

abscess  of,  516 
acetabulum,  501 
ankylosis  of,  479 
bones  of,  499 
femur,  582 
innominate,  499 
Bryant's  triangle,  505 
coxalgia  or  coxitis,  515 
abscess  in,  516 
attitude,  516 
measurements,  516 
symptoms,  515 
coxa  valga,  517 

vara,  517 
dislocations  of,  508 

catching  of  sciatic  nerve  in,  514 

freeing  of,  514 
classifications  of,  508 
complicated  by  fracture,  514 

reduction  of,  514 
congenital,  514 

reduction  of,  515 
signs  of,  515 
infolding  of  capsule  or  muscle  in,  514 
injuries  to  muscles  in,  511 
injuries  to  nerves  in,  511 
mechanism  of  production,  509 
reduction,  direct  method,  512 

indirect  method,  513 
rent  in  capsule,  511 
reversed  dislocations,  514 
signs  of,  512 
hip- joint,  506 

amputation  at,  532 
disease  of,  515 
hyperabduction  of,  496 
hyperadduction  of,  496 
hyperflexion  of,  496 
ligaments  of,  507 
capsular,  508 
iliofemoral,  507 
ischiofemoral,  507 
pubofemoral,  507 
movements  of,  504 

muscles  controlling,  504 
operations  on,  517 
anterior,  519 
Boeckman's,  518 
inferior,  519 
lateral,  517 
Lorenz's,  518 
iliotrochanteric  line,  anterior,  505 

posterior,  504 
ligation  of  gluteal  artery,  505 

of  internal  pudic  artery,  505 
of  sciatic  artery,  505 
muscles  of,  503 
Roser-N^laton  line,  502,  505 
surface  anatomy  of,  504 
Hour-glass  stomach,  401 
Housemaid's  knee,  538 
Houston,  valves  of,  439 
Humerus,  221,  267,  280 

epiphysis  of,  lower,  300 

separation  of,  300 
separation  of  upper,  247 
excision  of  head  of,  251 
fracture  of,  above  the  condyles,  295 


»I4 


INDEX 


Humerus,  fracture  of,  above  the  condyles,  treat- 
ment, 295 
intercondylar  or  T  fracture,  298 

treatment,  298 
involving  the  condyles,  296 
extra-articular,  296 
intra-articular,  297 
treatment,  297 
shaft,  276 

above  insertion  of  deltoid,  277 
below  insertion  of  deltoid,  277 
injury  to  radial  nerve,  277 
non-union  in,  277 
tipper  end,  244 

anatomical  neck,  244 
surgical  neck,  245 
tuberosities,  245 
lower  end  of,  280 
shaft  of,  207 
upper  end  of,  221 
Hunter's  canal,  524 
Hydatid  of  Morgagni,  453 
Hydrocele,  384 

of  canal  of  Nuck,  385,  468 
congenital,  384,  468 
encysted,  of  cord,  384,  468 
of  neck,  170 
Hydrocephalus,  acute,  23 
Hymen,  463 

Hypochondriac  region  of  abdomen,  370 
Hypogastric  region  of  abdomen,  370 
Hypoglossal  nerve,  20,  137 

injury  to,  in  fractures  of  skull,  20 
Hypothenar  eminence,  353 
Hysterectomy,  460,  461 
vaginal,  462 

Ileocaecal  fold,  413 

inferior,  414 
superior,  413 
fossa,  inferior,  414 
superior,  413 
valve,  374,  412 
Ileocolic  artery,  412 
Ileum  (see  Intestine,  small) 
Iliac  arteries,  436 

ligation  of,  436 

collateral  circulation  after,  437 
line  of,  374,  436 
region  of  abdomen,  370 
veins,  position  of,  374 
Iliohypogastric  nerve,  381 

injury  to,  in  abdominal  incisions,  381 
Ilio-inguinal  nerve,  381 
Iliopectineal  line,  434 
Iliotrochanteric  angle,  505 
line,  anterior,  505 
posterior,  504 
Ilium,  499 

Imperforate  anus,  442 
Incisions,  abdominal,  381 

for  abscess  of  axilla,  264 

in  abscess  of  parotid  gland,  54 

Battles,  abdominal,  382 

Edebohls,  for  kidney,  382 

for  empyema,  200 

for  glands  of  neck,  158 

for  glossitis,  no 

Kocher's,  for  gall-bladder,  382 

lumbar,  395,  428 

longitudinal,  395 
oblique,  396 
McBurn'jy's,  for  appendix,  382,  414 


Incisions  for  operating  on  the  forearm,  328 
Pfannenstiel's  abdominal,  382 
for  palmar  abscess,  365 
for  plantar  abscess,  575 
for  removal  of  breast,  187 
Stimson's  abdominal,  382 
transverse,  for  appendicitis,  414 
Weir's  abdominal,  382 
Inflammation  of  dura,  22 
of  pia  mater,  23 
of  scalp,  5 
Infra-orbital  nerve,  56,  94 

removal  of,  56 
Infraspinatus  bursa,  255 
Infrastemal  depression,  180 
Infratemporal  crest,  47 
Infundibulum  of  nose,  100 
Ingrown  toe-nail,  5  79 
Inguinal  adenitis,  527 
canal,  385 

columns  of,  external,  385 

internal,  385 
walls  of,  386 

anterior,  386 
floor,  386 
posterior,  386 
roof,  386 
fossae,  external,  387 
internal,  387 
middle,  387 
hernia  (see  Hernia) 
Inion,  39 

Interarticular  cartilage  of  jaw,  64 
triangular  fibrocartilage,  332 
Intercolumnar  fascia,  377,  386 
Intercondylar  fracture  of  humerus,  298 
Intercostal  arteries,  1 76 
anterior,  176 
posterior,  177 
nerves,  380 

anterior  branches,  380 
lateral  cutaneous  branches,  380 
Internal  capsule,  38 

functions  of,  38 
oblique  muscle,  377 
pudic  artery,  440,  474,  476 
ligation  of,  505 
nerve,  476 
Interossei  muscles,  353 
Interosseous  membrane  between  radius  and  ulna, 

304 
Intersigmoid  fossa,  417 
Intestine,  large,  374,  411 
anal  canal,  439 

blood-vessels  of,  440 
examination  of,  442 
external  sphincter,  440 
fissures  of,  443 
fistula  in  ano,  443 
hemorrhoids,  442 
imperforate  anus,  442 
internal  sphincter,  439 
lymphatics  of,  44 1 
mucous  membrane  of,  440 
nerves  of,  442 
valves  of,  440 
white  line  of  Hilton,  440 
appendix,  374,  412 
appendicitis,  414 

operation  for,  414 
blood  supply  of,  412 
lymphatics  of,  414 
mesoappendix,  412 


INDEX. 


615 


Intestine,  large,  appendix,  position  of, -^"74,  413 
veins  of,  413 
blood  supply  of,  412 
caecal  folds,  413 
fossae,  413 
caecum,  374.  401.  411 
lymphatics  of,  414 
position  of,  374,  400 
types  oi,  411 
colon,  ascending,  416 

position  of,  400 

relation  of,  to  tumors  of  kidney, 
427 
descending,  417 

in  colostomy,  417 
position  of,  401 
hepatic  flexure,  411 

position  of,  374 
iliac,  417 

in  inguinal  colostomy,  417 
intersigmoid  fossa,  417 
pelvic,  417 
sigmoid  flexure,  417 
splenic  flexure,  411 

position  of,  374 
transverse,  416 

position  of,  374,  400 
ileocaecal  valve,  374,  412 
position  of,  374 
rectum,  438 

ampulla  of,  438 
blood-vessels  of,  440 
excision  of,  443 
lymphatics  of,  441 
mucous  membrane  of,  440 
pelvi-rectal  bands,  443 
peritoneal  relations  of,  439 
prolapse  of,  435 
rectal  examination,  439,  442 
recto-urethralis  muscle,  438 
valves  of  Houston,  439 
sacculations  of,  411 
size  of,  411 
small,  374,  406 
coils  of,  408 
duodenum,  374,  486 

duodenojejunal  flexure,  408 

fossa,  408 
peritoneal  covering  of,  408 
position  of,  374 
relations  of,  407 
ileum,  374,  408 

position  of,  374 
jejunum,  374,  408 

duodenojejunal  flexure,  408 
fossa,  inferior,  408 
superior,  408 
muscle  or  ligament  of  Treitz,  408 

constriction  of  intestine  by,  408 
position  of,  374 
Meckel's  diverticulum,  409 

strangulation    of    intestines  by, 
409 
operations  on,  409 
Peyer's  patches,  409 
position  of,  374,  401 
Intradural  hemorrhage  of  cord,  486 
Iris,  77,  79 

affections  of,  77,  79 
Ischiorectal  abscess,  476 
treatment,  476 
fossa,  476 
Ischiosacral  arch,  491 
Ischium,  499 


Jaw,  lower,  63 

dislocation  of,  66 
reduction  of,  67 

excision  of,  71 

excision  of  condyle  of,  71 

fractures  of,  67 

ligaments  of,  64,  66 

influence  on  pus  in  joint,  66 

movements  of,  65 

temporomandibular  articulation,  64 
upper,  54 

excision  of  lingual  nerve,  60 
mandibular  nerve,  60 

fractures  of,  54 

maxillary  nerve,  56 

removal  of,  through  the  ptery. 
goid  fossa,  58 

operations  on  Gasserian  ganglion,  60 

removal  of  infra-orbital  nerve,  56 

removal  of  Meckel's  ganglion,  57 

resection  of,  55 
Jejunum  (see  Intestine,  small) 
Joint  or  joints,  acromioclavicular,  222 

ligaments  of,  222 
ankle,  554 

distention  of,  555 

ligaments  of,  554 

movements  of,  554 
carpometacarpal,  movements  of,  353 
elbow,  282 

ligaments  of,  284 

movements  of,  282 
of  foot,  564 

ligaments  of,  564,  566 

location  of,  571 
of  hand,  352 

movements  of,  353 

synovial  membrane  of,  352 
suppuration  of,  352 
metacarpophalangeal,  position  of,  353 
midtarsal  or  Chopart's,  566,  572 
radio-ulnar,  inferior,  332 

superior,  283 
sacro-iliac,  433 
shoulder,  222 

ligaments  of,  223 

movements  of,  253 
sternoclavicular,  222 
subastragaloid,  564 

ligaments  of,  565 

sprain  of,  566 
tarsometatarsal  (Lisfranc's),  573 
temporomandibular,  64 
tibiofibular,  inferior,  554 

ligaments  of,  554 
wrist- joint,  333 

ligaments  of,  333 

movements  of,  333 

Keratitis,  77 

Key,  foramen  of,  22 

Kidneys,  373,  424 

abscesses  of,  428    , 

points  of  pointing  of,  428 
capsules  of,  426 

fatty,  426 

fibrous,  426 
displacements  of,  427 

floating  kidney,  427 

movable  kidney,  427 
hilum  of,  426 
lower  border  of,  373 
operations  on,  428 

delivering  the  kidney,  429 


6i6 


INDEX. 


Kidneys,  operations  on,  incisions,  395,  428 
nerves  encountered,  429 
pleura  in,  429 
incisions  into  kidney  substance,  429 
outer  edge  of,  373 
pelvis  of,  426,  430 

position  of,  373 
perirenal  fascia,  427 
position  of,  373 
pyelonephritis,  428 
relations,  deep,  425 

anterior  surface,  425 
posterior  surface,  425 
to  surface,  424 
sinus  of,  426 
suprarenal  glands,  430 
tumors  of,  427 
upper  border  of,  373 
ureter,  430 

course,  431 
operations  on,  431 
vessels  of,  426 
Knee,  533 

amputation  through  knee-joint,  544 
bow-legs,  543 

treatment,  544 
bursae  of,  538 
dislocation  of,  541 

subluxation,  541 
epiphyseal  separations  of,  541 
ganglion  of,  539 
knee-joint,  534 

ligaments  of,  535 
lines  of,  534 
movements  of,  534 
pus  in,  535,  536 
semilunar  cartilages  of,  538 
dislocation  of,  541 
knock-knee,  543 

treatment,  544 
osteotomy  of  femur,  544 
patella,  535 

dislocation  of,  540 
fractures  of,  539 
resection  of,  542 
surface  anatomy  of,  533 
tuberculous  disease  of,  543 
Knock-knee,  543 

treatment,  544 
Kocher's  incision  for  gall-bladder,  382 

for  removal  of  Meckel's  ganglion,  58 
Kronleins  operation,  77 
Kyphosis,  479 
rachitic,  479 

Labia  majora,  462 

minora,  462 
Laceration  of  perineum,  464 

operation  for,  465 
Lachrymal  bones,  8 

canals,  72,  84 

gland,  72,  83 

sac,  72,  84 
Lachrymonasal  duct,  72,  84,  99 

stricture,  7,  84 
Lambda,  39 
Laminectomy,  489 
Laryngitis,  127 
Laryngoscopy,  126 
Laryngotomy,  126,  162 
Larynx,  124 

cricoid  cartilage,  126 

cricothyroid  membrane,  125 


Larynx,  diseases  of,  127 
epiglottis,  124 
foreign  bodies  in,  122 
operations  on,  161 
paralysis  of  muscles  of,  127 
thyrohyoid  membrane,  125 
thyroid  cartilage,  125 

fracture  of,  125 
valleculae  of,  124 

foreign  bodies  in,  124 
Lateral  curvature  of  spine  (see  Scoliosis) 
sclerosis,  488 
sinuses  (see  Sinus) 
Latissimus  dorsi  muscle,  269,  392 
I-eg,  545 

amputation  of,  552 
arteries  of,  548 
fascia  of,  548 
fractures  of,  551 
lymphatics  of,  551 
muscles  of,  546 

actions  of,  547 
surface  anatomy  of,  546 
veins  of,  550 

varicosities  of,  550 

operation  for,  551 
Lens  of  eye,  77 

cataract  of,  78 
Lenticular  nucleus,  31 
Lenticulostriate  ganglion,  28 
blood  supply  of,  28 
Lesser,  triangle  of,  146 
Levator  ani  muscle,  434 
Ligament  or  ligaments; 

acromioclavicular,  222 

alaria,  of  knee,  538 

annular,  anterior,  of  wrist,  335 

structures  passing  beneath,  336 
structures  passing  over,  336 
annular,  posterior,  of  wrist,  336 

structures  passing  beneath,  337 
anterior,  of  elbow,  284 
of  Bigelow,  507 
of  bladder,  445 
false,  445 
true,  445 
broad,  455 
of  Burns,  390 

calcaneoscaphoid,  inferior,  566 
capsular,  of  ankle,  554 
of  hip,  508 

of  inferior  radio-ulnar  articulation,  333 
of  knee,  535 
of  shoulder,  223 
of  wrist,  sii 
conoid,  222 
coraco-acromial,  222 
coracoclavicular,  222 
coracohumeral,  222,  225 
coronary,  of  knee,  538 

of  liver,  397,  418 
costocoracoid,  222,  257 
cotyloid  of  hip,  506 
crucial  of  knee,  537 
deltoid  of  ankle,  554,  565 
denticulate,  485 
of  ductus  venosus,  419 
falciform  of  liver,  419 
of  foot,  564 
Gimbernat's,  377,  390 
glenohumeral,  222,  225 
glenoid  of  shoulder,  223,  226 
of  hip,  507 


INDEX. 


6iy 


Ligamont,  iliofemoral,  507 

infundibulopelvic  or  suspensory  of  the  ovary, 

455-  456 
interclavicular,  222 
interosseous  astragalo-calcaneal,  565 
ischiofemora',  507 
of  knee,  535 
lateral,  external,  of  ankle,  554,  565 

of  elbow,  284 

of  knee,  537 

of  wrist,  2^2 
internal,  of  ankle,  554,  565 

of  elbow,  284 

of  knee,  537 

of  wrist,  333 
left,  of  liver,  398 
lienophrenic,  424 
lienorenal,  399,  424 
ligamentum  mucosum  of  knee,  538 
ligamentum  teres,  506 
of  liver   418 
mucosa  of  knee,  538 
orbicular,  283 
orbitotarsal,  6,  74,  82 
of  ovary,  456 
palpebral,  external,  82 

internal,  82,  84 
phrenocolic,  424 
plantar,  long,  567 

short,  566 
posterior  of  elbow,  284 
Poupart's,  377 
pubofenioral,  507 
puboprostatic,  445 
radio-ulnar,  anterior,  333 

posterior,  333 
rhomboid,  222 
round,  of  liver,  419 

of  uterus,  456 
sacrosciatic,  great,  434 

lesser,  434 
of  shoulder- joint,  223 
of  spleen,  424 
sternoclavicular,  222 
of  sternoclavicular  joint,  222 
stylohyoid,  132 
suspensory,  of  jejunum,  408 
temf)oromandibular,  64 
of  tempormandibular  articulation,  64 
transverse,  of  knee,  538 
trapezoid,  222 
of  Treitz,  406 
triangular,  473 

anterior  layer,  473 
deep  layer,  473 
xitero-ovarian,  456 
uterosacral,  455 
of  uterus,  455 
of  Wrisberg,  537 
of  Zinn,  81 
Ligation  of  axillary  artery,  first  portion,  259 

third  portion,  262 
of  brachial  artery  in  arm,  274 

at  elbow,  290 
of  carotid  artery,  common,  141 

external,  144 

internal,  143 
of  femoral  artery  in  Hunter's  canal,  525 

in  Scarpa's  triangle,  523 
of  gluteal  artery,  505 
of  iliac  arteries,  436 
of  internal  pudic  artery,  505 
of  lingual  artery,  145 


Ligation  of  peroneal  artery,  550 
of  popliteal  artery,  544 
of  radial  artery,  on  dorsum  of  hand,  348 
of  sciatic  artery,  505 
of  subclavian,  147,  148 
of  thyroid,  inferior,  149 

superior,  145 
of  tibial  artery,  anterior,  548 

posterior,  549 
of  ulnar  artery,  316 

lower  third,  317 
■  middle  third,  316 
upper  third,  316 
Linea  alba,  371 
Lineae  albicantes,  372 
semilunares,  372 
transversae,  372 
Lingual  nerve,  excision  of,  60 

exposure  through  mouth,  117 
Lips  (see  Mouth) 
Lisfranc's  amputation,  575 
Lithotomy,  lateral,  476 

median,  475 
Liver,  372,  417 

abscesses  of,  420 
biliary  passages,  420 

common  duct,  421 
cystic  duct,  421 
hepatic  duct,  421 
fissures  of,  418 
gall-bladder,  420 
gall-stones,  422 

operations  for,  422 
hepatic  artery,  421 
injuries  to,  420 
kidney  pouch,  422 
ligaments  of,  418 
liver  dulness,  372 
lobes  of,  417 
lower  border  of,  372 
lymphatic  nodes  of,  422 
portal  obstruction,  420 

anastomosis  of  superficial  veins  in,  4  20 
position  of,  372,  399,  419 
relations  of,  419 
size  of,  419 
upper  border  of,  372 
wounds  of,  420 
Lobes  of  brain,  32 

of  liver,  417 
Locomotor  ataxia,  488 
Longitudinal  fissure  of  brain,  33,  39 
Lordosis,  479 

Lorenz's  operation  on  hip,  518 
Lower  level  of  the  brain,  40 
Ludwig's  angina,  132 
Ludwig,  angle  of,  180 
Lumbar  abscess,  394 
fascia,  393 

anterior  layer  of,  393 
middle  layer  of,  393 
posterior  layer  of,  393 
hernia,  394 
incisions,  395 

longitudinal,  395 
oblique,  396 
puncture,  488 
region  of  abdomen,  370 
fascias  of,  393 
hernias  of,  394 
incisions  in,  395 
muscles  of,  392 
Petit's  triangle,  394 


6i8 


INDEX. 


Lumbricales  muscles,  353 
Lungs,  196 

in  emphysema,  196 

empyema,  201 

general  considerations  of,  198 

lobes  of,  198 

outline  of,  197 

anterior  border,  198 

apex,  198 

lower  border,  199 
in  phthisis,  197 
Lymphatics  of  alidominal  walls,  380 
of  anal  canal,  441 
of  appendix,  414 
of  axilla,  263 
of  caecum,  414 
of  groin,  527 

excision  of,  527 
of  hand,  368 
of  leg,  551 
of  liver,  422 
of  mammary  gland,  184 
of  neck,  156 

abscess  of,  154 

operation  on,  158 
of  nose,  98 
of  ovary,  459 
of  rectum,  441 
of  scalp,  4 
of  stomach,  403 
of  uterus,  458 

Macewen,  suprameatal  triangle  of,  91 
Magendie,  foramen  of,  22 
Malar  bone,  8,  44,  49 

fracture  of,  49 
tubercle,  40 
Mammary  gland,  182 

abscess  of,  185 
blood  supply  of,  183 
fibrous  structure  of,  183 
lymphatics  of,  184 
nerves  of,  185 
nipple,  183 

removal  for  carcinoma,  187 
secreting  structure  of,  182 
tumors  of,  185 
benign,  185 
malignant,  186 
removal  of,  187 
Mandible  (see  Jaw,  lower) 
Mandibular  nerve,  60 
excision  of,  60 

exposure  of.  through  the  mouth,  117 
Marginal  convolution  of  brain,  34 
Masseter  muscle,  65 
Mastoid  antrum,  in  adults,  11 
in  childhood,  9 
operations  on,  91 
cells,  11 ,  90 

operation  on,  91 
process,  4,11 
Maxilla,  inferior  (see  Jaw,  lower) 

superior  (see  Jaw,  upper) 
Maxillary  artery,  internal,  50,  58 
nerve,  56 

neuralgia  of,  55 

operations  on,  through  pterygoid  fossa,  58 
sinus  (see  Sinus) 
Mayo  incision  for  gastrectomy,  405 
Mayo  Robson's  incision  for  kidney,  429 
McBumey's  incision  for  appendix,  382,  414 
point,  374,  414 


Measurement  of  lower  timm^97 
Meatus,  auditory,  external,  84 
inferior,  of  nose,  99 
middle,  of  nose,  100 
superior,  of  nose,  100 
Meckel's  diverticulum,  372,  382,  409 

strangulation  of  intestines  by,  383,  409 
ganglion,  58 

removal  of,  57 
Median  nerve,  318 

branches  of,  319 
distribution  of,  in  hand,  360 
operations  on,  319 
wounds  of,  319 
Mediastinum,  187 
anterior,  189 

abscess  of,  190 

paracentesis  of  the  pericardium  through, 
190 
middle,  190 

enlarged  glands  in,  190 
posterior,  190 
superior.  188 

abscess  in,  189 
aneurism  in,  189 
tumors  in,  189 
tumors  of,  191 
Medulla,  31 
Meibomian  glands,  82 
Meninges  of  brain,  20 

afTections  of,  22 
arachnoid,  21 
dura  mater,  20 

hemorrhage  into,  23 
pia  mater,  22 
of  spinal  cord,  484 
arachnoid,  485 
dura  mater,  484 
pia  mater,  485 
subarachnoid  space,  485 
subdural  space,  485 
Meningitis,  23 

tuberculous,  23 
Meningocele,  7 
Mesentery,  374,  398,  410 

influence  of,  upon  blood  in  abdominal  cavity, 

210 
lymph-nodes  of,  410 
Mesocolon,  398 
Mesosalpinx,  456 
Metacarpal  bones,  350 

dislocations  of,  362 
fractures  of,  364 

treatment  of,  364 
Metacarpophalangeal  joints,  position  of,  356 
Metatarsalgia,  580 
Middle  meningeal  hemorrhage,  1 7 

trephining  for,  18 
Midf rental  area  of  brain,  35 
function  of,  38 
Miner's  elbow,  300 
Monro,  foramen  of,  30 
Morgagni,  columns  of,  440 

crypts  of,  440 
Morton's  disease,  580 
Motor  track  of  brain,  39 

functions  of,  39 
Mouth,  104 

cysts  of,  mucous,  no 
lingual  nerve,  117 
lips,  104 

angioma  of,  104 
blood  supply  of,  104 


INDEX. 


619 


Mouth,  lips,  cancer  of,  105 

harelip,  105 

paralysis  of,  106 

wounds  of,  104 
mandibular  nerve,  117 
palatal  arches,  112 
palate,  iii 

blood  supply  of,  1 1 1 

cleft.  III 

operation  for,  112 

foramina  in,  in 

hard,  iii 

soft.    III 

roof  of.  III 

blood  supply  of,  in 

foramina  in,  in 
surface  anatomy  of,  107 
tongue,  107 
tonsils,  faucial,  113 

lingual,  108 
Movable  kidney,  427 
Muscle  or  muscles: 

abductor  minimi  digiti,  354 
abductor  pollicis,  354 
accelerator  urinae,  471 
adductor  brevis,  522 

longus,  522 

magnus,  522 

pollicis,  354  -» 

anconeus,  286 
biceps,  269,  284,  310 

tendon  of,  255 

dislocation  of,  269 
rupture  of,  270 

of  thigh,  520 
brachialis  anticus,  270,  284 
brachioradialis,  285,  286,  310 
buccinator,  65 
bulbocavemosus,  471,  474 
ciliary,  77 
coccygeus,  434 

compressor  urethrae,  471,  474 
coracobrachialis.  269 
cremaster,  377 
crureus,  520 
deltoid,  268 
digastric,  65 
dilator  pupilae,  79 
erector  spinas,  180,  392,  477 
extensor  brevis  digitorum,  572 
extensor  brevis  pollicis,  308 
extensor  carpi  radialis  brevior,  310,  334 
extensor  carpi  radialis  longior,  286,  309,  334 
extensor  carpi  ulnaris,  310,  334 
extensor  communis  digitorum,  308 
extensor  longus  digitorum,  546,  572 
extensor  longus  hallucis,  546,  572 
extensor  longus  pollicis,  308 
extensor  minimi  digiti,  308 
extensor  ossis  metacarpi  pollicis,  308 
flexor  brevis  minimi  digiti,  354 
flexor  brevis  pollicis,  354 
flexor  carpi  radialis,  308,  334 
flexor  carpi  ulnaris,  308,  334 
flexor  longus  digitorum,  546,  568,  572 
flexor  longus  hallucis,  546,  568,  572 
flexor  longus  pollicis,  307 
flexor  profundis  digitorum,  307 
flexor  sublimis  digitorum,  308 
gastrocnemius,  596 

bursa  of,  539 
geniohyoglossus,  65 
geniohyoid,  65 


Muscle,  gluteus  maximus,  504 

meJius,  504 

minimus,  504 
gracilis,  522 
iliacus,  434,  504 
intercostal,  external,  176 

internal,  176 
interossei  of  hand,  353 
ischiocavemosus,  474 
latissimus  dorsi,  180,  269,  392 
levator  anguli  scapulae,  138,  227 
levator  ani,  434 

palpebrae,  81 
masseter,  65 
mylohyoid,  65 
oblique,  external,  377 

inferior,  of  eye,  81 

internal,  377 

superior,  of  eye,  81 
obturator  extemus,  504,  522 

intemus,  504 
occipitofrontalis,  2 
omohyoid,  227 
opponens  minimi  digiti,  354 
opponens  pollicis,  354 
orbicularis  oris,  104 
obicularis  palpebrarum,  82 
palatoglossus,  113 
palatopharyngeus,  13 
palmaris  brevis,  354 

longus,  308,  334 
pectineus,  522 
pectoralis  major,  177,  269 

minor,  178 
perineal,  deep,  transverse,  474 

superficial,  474 
peroneus  brevis,  546,  568,  572 

longus,  546,  568,  572 

tertius,  546,  568,  .<;72 
action  of,  569 
plantaris,  546 
platysma,  65 
pronator  quadratus,  310 

radii  teres,  284,  310 
psoas,  434,  504 
pterygoid,  65 
pyramidalis,  375 
pyriformis,  504 
quadratus  femoris,  504,  523 

lumborum,  392 
quadriceps  extensor,  5  20 
recto-urethralis,  438 
rectus  abdominis,  375 
sheath  of,  375 

external,  of  eye,  81 

femoris,  520 

inferior,  of  eye,  81 

internal,  of  eye,  81 

superior,  of  eye,  81 
rhomboid,  227 
sartorius,  5  20 
scalenus  anticus,  138 

medius,  138 

posticus,  138 
semimembranosus,  521 
semitendinosus,  520 
serratus  anterior  (magnus),  179,  227 
soleus,  546 

sphincter  ani,  external,  440 
internal,  439 

internal,  of  bladder,  471 

pupillae,  79 
splenius,  138 


620 


INDEX. 


Muscle,  sternohyoid,  122 
sternomastoid,  4 

division  of,  for  torticollis,  4 
subclavius,  226 
supinator  brevis,  316 
temporal,  48,  65 
tensor  tarsi,  84 
tibialis  anterior,  546,  568,  572 

posterior,  546,  568,  572 
transversalis,  378 
trapezius,  4,  180,  227 
of  Treitz,  408 

constriction  of  intestines  by,  408 
triceps,  270,  286 
vastus  extemus,  520 

intemus,  520 
Musculospiral 
groove,  267 
nerve,  265,  277 

paralysis  of,  277 
Mynter,  operation  for  excision  of  wrist,  347 

Naevus,  7 

Nares,  anterior,  96 
posterior,  118 
Nasal  bones,  8 
Nasion,  39,  46 
Neck,  127 

abscess  of,  153 

influence  of  cervical  fascias  on,  154 
arteries  of,  141 
cervical  ribs,  175 
triangles,  131 
cut  throat,  168 
cysts  of,  169 

median,  170 
sebaceous,  151 
diseases  affecting,  128 
fascias  of,  150 

influence  on  pus  in  neck,  154 
fistulae  of,  169 

median,  170 
hydrocele  of,  170 
injuries  to,  128 
lymphatics  of,  156 
abscess  of,  153 
operation  on,  156 
oesophagus,  cervical  portion,   166 
foreign  bodies  in,  167 
CESophagotomy,  167 
sheath  of  vessels  of,  153 

pus  in,  155 
surface  anatomy  of,  128 

laryngeal  region,  129 
structures  felt  in  median  line,  130 
submental  region,  129 
tracheal  region,  129 
torticollis,  140 

treatment  of,  140 
triangles,  cervical.  131 
Nerve  or  nerves: 

abducens,  20,  82 
auditory,  20 

auricularis  magnus,  44,  52,  139 
auriculotemporal  branch  of  fifth,  3,  52 
axillary  (see  Nerve,  circumflex) 
circumflex,  265 

cutaneous,  internal,  of  arm,  265 
internal,  of  leg,  523 
lesser  internal,  265 
dental,  anterior,  56 

inferior  (see  Mandibular  nerve) 
posterior,  56 


Nerve,  descendens  hypoglossi,  liy 
facial,  20,  52 

paralysis  of,  82 
fourth  (see  Pathetic  nerve) 
frontal  branch  of  fifth,  82 
genitocrural,  451 
glossopharyngeal,  20 
hemorrhoidal,  inferior,  442,  476 
humeral,  265 
hypoglossal,  20,  137 
iliohypogastric,  387,  429 

injury  to,  in  abdominal  incisions,  381 
ilio-inguinal,  381,  429 
infraorbital,  of  maxillary,  56,  94 

removal  of,  56 
infratrochlear,  94 
intercostal,  380 

anterior  branches,  380 

lateral  branches,  380 
intercostobrachialis,  185,  265 
interosseus,  anterior  (volar),  320 

posterior,  321 
labial,  of  maxillary,  56 
lachrymal  of  fifth,  82 
laryngeal,  superior,  125,  137 
lingual,  60 

excision  of,  60 

exposure  in  mouth,  117 
long  subscapular,  265 
mandibular,  60 

excision  of,  60 

exposure  of,  through  mouth,  117 

operations  on,  through  pterygoid  fossa,  58 
maxillary,  56 

neuralgia  of,  55 

operations  on,  through  pterygoid  fossa,  58. 
medial  brachial  cutaneous,  185 
median,  318 

distribution  of,  in  hand,  360 

operations  on,  319 

wounds  of,  319 
musculocutaneous,  265 
musculospiral,  265,  277 

paralysis  of,  278 
nasal,  of  maxillary,  56,  82,  94 
occipitalis  major,  4 

minor,  44,  139 
oculomotor,  19,  82 

injury  to,  in  fracture  of  skull,  19 

paralysis  of,  82 
olfactory,  19,  94 

injuries  to,  in  fracture  of  skull,  19 
optic,  19,  79,  82 

injury  to,  in  fracture  of  skull,  19 
orbital,  of  maxillary,  56 
palpebral,  of  maxillary,  56 
pathetic,  20,  82 

paralysis  of,  82 
p)erineal,  external  or  anterior,  474,  476 

internal  or  posterior,  474,  476 
phrenic,  179 
pneumogastric,  137 
popliteal,  543 
pudic,  474,  475,  476 
radial,  265  ;  in  arm,  277 

in  forearm,  321 

in  hand,  360 
respiratory,  long  external  of  Bell,  179 
saphenous,  internal,  523 

long,  526 
sciatic,  large,  527 

sciatica,  528 
sphenomalar,  of  maxillary,  56 


INDEX. 


621 


Nerve,  sphenopalatine  branch  of  maxillary,  56 
spinal  accessory,  20,  139 
superficial  cervical,  139 
supra-orbital,  45 

operation  on,  46 
terminal,  of  maxillary,  56 
third  (see  Oculomotor) 
thoracic,  last,  420 
posterior,  179 
thoracodorsalis,  265 
trifacial,  20 

area  of  distribution  of,  63 
ulnar,  265,  320 

distribution  in  hand,  360 
operations  on,  320 
■wounds  of,  320 
vagus,  20,  137 
Neuralgia  of  maxillary  nerve,  55 
Nipple,  181,  183 
Noma,  49 
Nose,  94 

arteries  of,  98 
bleeding  from,  98 
bony  portion,  95 
bulla  ethmoidalis,  100 
cartilaginous  portion,  95 
epistaxis,  98 
ethmoidal  sinuses,  102 
frontal  sinuses,  lor 
hiatus  semilunaris,  97,  100 
injuries  to,  95 

dislocations,  95 
fracture,  95 
lachrymonasal  duct,  99 
lymphatics  of,  98 
maxillary  sinus  or  antrum,  103 
meatus,  inferior,  99 
middle,  100 
superior,  100 
mucous  membrane  of,  99 

hypertrophies  of,  99 
nares,  anterior,  96 
view  of,  96 
posterior,  118 
nasal  hypertrophies,  99 
anterior,  99 
posterior,  99 
nerves  of,  94 
obstruction  of,  94 
septum,  97 

deviations  of,  97 
haematomas  of,  97 
hypertrophies  of,  118 
spurs  of,  97 
spheno-ethmoidal  recess,  10 1 
spehnoidal  sinus,  103 
turbinated  bone,  inferior,  96 

hypertrophy  of,  anterior,  99 
jxjsterior,  99,  118 
middle,  97 
superior,  97 
veins  of,  98 
wall,  outer,  99 
Notch,  suprasternal,  180 

Occipital  artery,  3,  4 

bone,  8 

convolutions  of  brain,  ^3 

lobe  of  brain,  32 

blood  supply  of,  29 

protuberance,  4 

sinus,  13 
Occipitalis  major  nerve,  4 


Occipitofrontalis  muscle,  2 
Oculomotor  nerve,  19,  82 

injury  to,  in  fractures  of  skull,  19 
paralysis  of,  82 
Qi^sophagotomy,  167 
Oesophagus,  166,  211 
carcinoma  of,  212 
cervical  portion,  166 
dilatation  of,  212 
diverticula  of,  212 
foreign  bodies  in,  167,  212 
crsophagotomy,  167 
relations  of,  211 
structure  of,  212 
tumors  of,  211 
Olecranon,  281 
bursa  of,  300 

disease  of,  300 
fracture  of,  298 
Olfactory  area  of  brain,  37 
nerve,  19,  94 

injuries  to,  in  fracture  of  skull,  19 
Oilier,  operation  for  excision  of  wrist,  346 
Omentum,  gastrohepatic,  397 
gastrosplenic,  399 
greater,  398,  399 

anterior  layer  of,  398 
posterior  layer  of,  398 
lesser,  398 
Oophorectomy,  460,  461 
Ophthalmic  artery,  3,  81 
Optic  chiasm,  79 
disk,  80 

affections  of,  80 
nerve,  19,  79,  82 

injuries  to,  in  fractures  of  skull,  19 
neuritis  of,  80 
Orbicular  ligament,  283 
Orbjfotarsal  ligaments,  6,  74 
Orbits,  72 

abscess  of,  75 
affections  of,  71; 
blood-vessels  of,  81 
contents  of,  74 
dermoids,  75 
emphysema  of,  76 
foreign  bodies  in,  76 
hemorrhage  into,  77 
inferior  orbital  fissure,  74 
Kronlein's  operation,  77 
margins  of,  45 
muscles  of, 

levator  palpebrae,  8r 
oblique,  inferior,  81 

superior,   81 
rectus,  external,  8r 
inferior,  81 
internal,  81 
superior,  81 
nerves  of,  82 
periosteum  of,  74 
rim  of,  72 

spehnoidal  fissure,  74 
sphenomaxillary  fissure,  74 
superior  orbital  fissure,  74 
tumors  of,  75 
walls  of,  72 
Orchitis,  469 
Os  magnum,  350 
Osteotomy  of  femur,  544 

of  tibia,  544 
Ovarian  artery,  458 
Ovary,  456 


622 


INDEX. 


Ovary,  blood-supply  of,  458 
development  of,  453 
ligaments  of,  456 
lymphatics,  459 
oophorectomy,  460,  461 

Pacchionian  bodies,  21 
Pachymeningitis,  22 
externa,  22 
interna,  22 
Palate,  arches  of,  112 
blood-supply  of,  in 
cleft  palate,  in 

operation  for,  112 
hard,  in 
palate  bone,  8 
soft,  in 
Palmar  abscess,  365 

incisions  for,  365 
arch,  deep,  359 

superficial,  358 
fascia,  357 

abscess  beneath,  365 
Pampiniform  plexus,  385 
Panaris,  367 
Pancreas,  373,  422 
abscess  of,  423 

evacuation  of,  423 
cysts  of,  423 

directions  of  enlargement  of  growths  of,  423 
ducts  of,  423 
position  of,  373 
relations  of,  423 
Pannus,  77 
Paracentesis  of  chest,  201 

pericardii,  190,  202 
Paracentral  lobule  of  brain,  34 
Paradidymis,  453 
Paralysis,  crossed,  of  pons,  32 
of  larynx,  127 
of  lips,  106 

of  musculospiral  nerve,  278 
Parathyroid  bodies,  165 
Parietal  bones,  8 
eminences,  8 
lobe  of  brain,  32 

blood-supply  of;  28 
Paroophoron,  453 
cysts  of,  454 
Parotid  duct,  51 

calculus  of,  51 
fascia,  52 
gland,  3,  SI 

abscess  of,  53 

incisions  for,  54 
affections  of,  53 
capsule  of,  153 
lobes  of,  52 
lymphatics  of,  53 
nerves  traversing,  52 
tumors  of,  54 
vessels  traversing,  5  2 
Parotiditis,  53 

suppurative,  53 
Parovarium  or  organ  of  Rosenmtiller,  454 
Patella,  534,  535 

dislocations  of,  540 
treatment,  541 
floating  patella,  536 
fractures  of,  439 

by  direct  violence,  540 
by  indirect  violence,  539 
treatment,  .1^40 


Pathetic  nerve,  20,  82 

injuries  to,  in  fractures  cf  skull,  20 
paralysis  of,  82 
Pectoralis  major  muscle,  269 
Pectoralis  minor,  178 
Pelvic  examination,  459 
Pelvi-rectal  bands,  443 
Pelvis,  432 

bones  of,  432,  499 
bony  pelvis,  490 

arches  of,  femorosacral,  490 

ischiosacral,  491 
distorsions  of,  due  to  affections  of  lower 
extremity,  496 
correction  of,  496,  497 
effect  on,  of  shortening  or  lengthening  the 

lower  extremity,  497 
tilting  of,  in  deviations  of  spine,  495 
correction  of,  495 
false,  432 
fascia  of,  435 

influence  of,  on  pointing  of  pus,  43O 
female,  433 

diameters  of,  433 
floor  of,  434 
foramina  of,  434 

structures  passing  through,  434 
fractures  of,  491 
hemiae  of,  435 
iliac  vessels,  436 
iliopectineal  line,  434 
influence  of  sex  on,  433 
inlet  of,  432 
ligaments  of,  434 
male,  433 
outlet  of,  433 

prolapse  of  rectum  and  vagina,  435 
true,  432 
viscera  of,  438 
walls  of,  434 
white  line  of,  435 
Penis,  465 

amputation  of,  466 
chordee,  466 
circumcision,  466 
crura  of,  474 

extravasation  of  urine  into,  466 
lymphatics  of,  466 
paraphimosis,  466 
phimosis,  466 
rupture  of,  466 
Pericardium,  201 

drainage  of,  203 
paracentesis  of,  190,  202 
Pericranium,  3 
Perineal  section,  475 

spaces  (see  Perineum,  male) 
Perineum,  female,  464 

laceration  of,  464 

operation  for,  465 
male,  472 

anal  triangle,  476 
bony  landmarks,  472 
central  point  of,  473 
extra vasion  of  blood  and  urine  into,  475 
fascias  of,  473 
Colles's,  473 
superficial,  473 
triangular  ligament,  473 
ischiorectal  abscess,  476 
treatment,  476 
ischiorectal  fossa,  476 
nerves  of,  476 


INDEX. 


623 


Perineum,  male,  operations  on,  475 
lithotomy,  lateral,  476 

median,  475 
perineal  section,  475 
perineal  spaces,  474 
deep,  474 
superfical,  474 
urogenital  triangle,  472 
vessels  of,  476 
Periosteum  of  orbit,  74 
Peritoneum,  396 

anteroposterior  section  of,  397 
caecal  folds,  413 

ileocaecal  fold,  inferior,  414 
ileocaecal  fold,  superior,  413 
retrocolic  fold,  414 
caecal  fossae,  413 

ileocaecal  fossa,  inferior,  414 
ileocaecal  fossa,  superior,  413 
retrocolic  fossas,  414 
cavity  cf,  greater,  397,  398 

lesser,  398 
coronary  ligament,  397 
foramen  of  Winslow,  398 
left  lateral  ligament  of  liver,  398 
lienorcnal  ligament,  399 
mesentery,  374,  398 
mesocolon,  transverse,  398 
omentum,  gastrosplenic,  399 
greater,  398 
lesser,  398 
recto-uterine  (Douglas's)  pouch,  398 
transverse  section  of,  398 
uterovesical  fold,  398 
Peritonsillar  abscess,  115 
Perivascular  lymph-sheath, 
Peroneal  artery,  550 

ligation  of,  550 
Petit's  triangle,  377,  394 
Petrosal  sinus,  inferior,  13 
Peyer's  patches,  409 
Pfannenstiel,  abdominal  incision  of,  382 
Phalanges,  351 

dislocation  of, 

distal  and  middle  phalanges,  363 
on  metacarpal  bones,  362 
proximal,  of  thumb,  362 
fractures  of,  364 

treatment  of,  364 
Pharyngitis,  123 
Pharyngotomy,  125 

subhyoidean,  16  r 
Pharynx,  117 

adenoids,  122 

removal  of,  122 
Eustachian  tube,  118 
foreign  bodies  in,  124 
fossa  >f  Rosenmuller,  123 
mucous  membrane  of,  1 23 
openings  into 

larynx,  121 

obstruction  at,  122 
mouth,  121 

contractures  of,  121 
oesophagus,  122 
posterior  nares,  118 
pharyngeal  tonsil,  122;  aponeurosis,  116 
pharyngitis,  123 

relation  of  internal  carotid  artery  to,  123 
retropharyngeal  abscess  (see  Abscess) 
Phimosis,  466 
Pial  hemorrhage,  23 
Pia  mater,  2  2 


Pigeon  breast,  172 
Piles  (see  Hemorrhoids) 
Pirogoff's  amputation,  560 
Pisiform  bone,  349 
Plantar  abscess,  575 
deep,  575 
incision  for,  575 
superficial,  575 
arteries,  572 

external,  572 
internal,  572 
ligation  of,  573 
fascia,  567 

abscess  beneath,  575 
Pleura,  194 

boundaries  of,  195 
empyema,  200 

in  lumbar  incisions,  195,  429 
paracentesis  of,  200 
pleural  effusion,  191 
Pleural  effusion,  191 

dilatation  of  heart  as  cause  of,  191 
Plexus,  brachial,  225 
choroid,  30 
pampiniform,  385 
Pneumogastric  nerve,  137 
Point,  pre-auricular,  40 
Rolandic,  inferior,  40 

superior,  40,  42 
Sylvian,  40,  42 
Pons,  31 

crossed  paralysis  of,  32 
hemorrhage  into,  32 
Popliteal  artery,  544 

ligation  of,  544 
Portal  obstruction,  420 

anastomosis  of  superficial  veins  in,  420 
vein,  420 
Postcentral  convolution  of  brain,  33 
Postprostatic  pouch,  446 
Pott's  disease  of  spine,  480 
fracture,  557 

treatment,  558 
position,  in  fractures  of  tibia,  551 
in  Potts'  fracture,  559 
Pouch  of  Douglas,  398,  454 
kidney,  422 
recto-uterine,  398 
Poupart's  ligament,  377 
Pre-auricular  point,  40 
Precentral  convolution  of  brain,  ^3 
Precuneus,  34 
Prefrontal  area  of  brain,  35 

functions  of,  35 
Prepatellar  bursa,  538 

inflammation  of,  538 
Process,  angular,  external,  of  frontal  bone,  40 
internal,  of  frontal  bone,  46 
coracoid,  181 
falciform,  390 
hamular,  112 
mastoid,  4 

styloid,  of  radius,  332 
of  ulna,  303 
Progressive  spinal  muscular  atrophy,  488 
Prolapse  of  rectum,  434 

of  vagina,  434 
Pronated  foot,  577 

treatment,  578 
Pronators  of  forearm,  304 
Prostatectomy,  450 
perineal,  450 
suprapubic,  450 


»24 


INDEX. 


Prostate  gland,  448 

abscess  of,  451 

capsule  of,  449 

hypertrophy  of,  449,  450 

prosiatectoniy,  450 
perineal,  450 
suprapubic,  450 

relations  of,  450 

separable  space,  451 

sheath  of,  449 

structure  of,  450 

veins  of,  450 
Psoas  abscess,  481 

muscle,  434,  504 
Pterion,  39,  42 
Pubic  bone,  499 
Puncta  lachrymalia,  84 
Pyelonephritis,  428 
Pylorectomy,  405 
Pyloroplasty,  405 

Quadrate  lobule  of  brain,  34 
Quadratus  lumborum  muscle,  393 

Rachitic  kyphosis,  479 

rosary,  172 
Radial  artery,  316,  359 
in  hand,  359 

branches,  360 
ligation  of,  on  dorsum  of  hand,  348 
fossa,  280 
nerve,  265,  277,  321 

branches  in  forearm,  320 
deep,  321 
superficial,  321 
volar  interosseous,  320 
distribution  in  hand,  360 
paralysis  of,  277 
tubercle,  dorsal,  331 
Radiocarpal  joint  (see  Wrist),  333 
Radio-ulnar  articulation,  inferior,  332 
dislocation  of,  345 
ligaments  of,  333 
movements  of,  333 
superior,  283 

ligaments  of,  283 
Radius,  281,  304 

dislocation  of  head  of,  295 

treatment,  295 
epiphysis  of,  lower,  344 

separation  of,  344 
upper,  300 

separation  of,  299 
fractures  of,  Colles's,  342 
treatment,  343 
head  and  neck,  299 
treatment,  299 
lower  end  with  forward  displacement,  344 
shaft,  322 

above    insertion    of    pronator    radii 

teres,  323 
below    insertion    of    pronator    radii 

teres,  323 
treatment,  323 
lower  end  of,  331 
operations  on,  328 
Ranula,  108  ;  treatment,  109 
Rectal  examinations,  439 
Rectocele,  435,  464 
Recto-urethralis  muscle,  438 
Recto-uterine  fold,  455 

pouch,  398 
Rectovesical  pouch,  446 


Rectum  (see  Intestine,  large) 
Rectus  abdominis  muscle,  375 

sheath  of,  375 
Region  or  regions: 

of  abdomen,  370 
epigastric,  370 
hypochondriac,  370 
hypogastric,  370 
iliac,  370 
lumbar,  370 
umbilical,  370 

of  ankle,  553 

of  arm,  266 

of  back,  477 

of  cheek,  49 

of  chest,  192 

of  elbow,  280 

of  eye,  72 

of  forearm,  303 

frontal,  45 

of  hip,  499 

of  knee,  533 

laryngeal,  129 

lumbar,  392 

of  neck,  127 

of  shoulder,  217 

spine,  477 

submaxillary,  pus  in,  154 

submental,  129 

temporal,  46 

of  thigh,  519 

tracheal,  1 29 

of  wrist,  330 
Reil,  island  of,  28,  33 
Renal  arteries,  426 
Resection  of  ankle,  555 

of  clavicle,  250 

of  condyle  of  lower-jaw,  71 

of  elbow,  301 

of  humerus,  upper  end,  251 

of  inferior  dental  nerve,  60 

of  jaw,  lower,  7 1 
upper,  55 

of  knee,  542 

of  lingual  nerve,  60 

of  maxilla,  superior  (see  Jaw) 

of  metatarsophalangeal  joint  of  foot,  580 

of  rectum,  443 

of  rib,  201 

of  scapula,  251 

of  tongue,  no 

of  ureter,  431 
Retina,  77,  82 

affections  of,  77,  82 

detachment  of,  77 

hemianopia,  82 
binasal,  82 
bitemporal,  82 
homonymous,  82 
lateral,  82 
Retrocolic  fold,  414 

fossa,  414 
Retropharyngeal  abscess,  90,  116,  123,  156 
treatment,  116 

space,  116 
Retzius,  foramen  of,  22 
Ribs,  174 

cervical,  175 

fracture  of,  175 
Ridge,  sublingual,  108 

supercilliary,  45 
Rings,  abdominal  (see  Abdomen) 
Rivinus,  duct  of,  108 


«l 


INDEX. 


625 


Rolandic  area  of  brain,  35 

functions  of,  3  ^^ 

point,  inferior,  40 
superior,  40,  42 
Rolando,  fissure  of,  33 
RosenmuUer,  fossa  of,  123 
Roser-X^laton  line,  502,  505 
Rupture  of  biceps  tendon,  270 

of  bladder,  446 

of  penis,  466 

Sacro-iliac  joint,  433 
Sacrosciatic  foramen,  greater.  434 
lesser,  434 

structures  passing  through,  434 
ligament,  greater,  434 
lesser,  434 
Salpingectomy,  460,  461 
Santorini,  cartilages  of,  124 
duct  of,  423 
fissures  of,  86 
Saphenous  opening,  390 
Sarcocele,  469 
Scalp,  1 

abscess  of,  5 

subaponeurotic,  6 
subcutaneous,  5 
subpericranial,  6 
affections  of  blood-vessels  of,  6 
aneurismal  varix,  6 
arterial  aneurism,  6 
cirsoid  aneurism,  6 
telangiectasis,  6 
treatment,  7 
varicose  aneurism,  6 
venous  angioma,  6 
arteries  of,  3 
contusions  of,  5 
haematomas  of,  5 
inflammation  of,  5 
layers  of,  i 

affections  involving,  4 
lymphatics  of,  4 
pericranium,  2 
tumors  of,  7 

cephalhydrocele,  7 
dermoid  tumors,  7 
encephalocele,  7 
meningocele,  7 
sebaceous  cyst,  7 
wounds  of,  4 

treatment  of,  5 
Scaphoid  bone  of  hand,  349 

of  foot,  562 
Scapula,  219 

excision  of,  251 
fractures  of,  243 

acromium  process,  244 
body,  244 

coracoid  process,  244 
glenoid  process,  244 
surgical  neck,  244 
separationof  epiphysis  of  acromion  and  cora- 
coid processes,  247 
winged,  180 
Scarpa's  fascia,  374 

triangle,  522 
Schede's  operation  for  varicose  veins,  557 
Schlemm,  canal  of,  79 
Schneiderian  membrane,  99 
Sciatica,  528 
Sciatic  nerve,  527 

exposure  of,  527 

40 


Sciatic  notch,  great,  504 
Sclerotic  coat  of  eye,  77 

affections  of,  77 
Scoliosis,  479,  495 
Scrobiculus  cordis,  180 
Scrotum,  467 

blood-supply  of,  467 

dartos  of,  467 

extravasation  of  blood  and  urine  into,  467 

treatment  of,  468 
operations  on,  467 
skin  of,  467 
Sebaceous  cyst  of  neck,  151 

of  scalp,  7 
Semilunar  bone,  349 

cartilages  of  knee,  538 

dislocation  of,  541 
fold  of  Douglas,  376 
Seminal  vesicles,  452 

operations  on,  452 
Sensory  area  of  brain,  37 
Septum  lucidum,  30 
Septum  of  nose  (see  Nose) 
Sheath  of  vessels  of  neck,  153 

pus  in,  155 
Shoulder,  217 

acromioclavicular  joint  of,  222 
affections  of,  218 
amputation  of,  247 
flap  method,  247 
interscapulothoracic,  250 
racket  method,  248 
axilla,  229 
bones  of,  219 
bursae  of,  255 

diseases  of  the  joint  and  bursae,  253 
dislocations  of,  232 
anterior,  232 

treatment,  236 
posterior,  239 
epiphyseal  separations  of,  247 
acromium,  247 
coracoid,  247 

upper  end  of  humerus,  247 
muscles  of,  226 
shoulder-girdle,  217 
fractures  of,  241 
movements  of,  227 
shoulder- joint,  222 

effusions  into,  255 
ligaments  of,  223 
movements  of,  253 
sternoclavicular  joint,  222 
surface  anatomy  of,  227 
Shrapnell's  membrane,  87 
Sigmoid  cavity,  greater,  281 
lesser,  303 
flexure,  417 

position  of,  401 
notch,  331 
sinus,  13 
Silver  fork  deformity,  343 
Sinus  or  sinuses: 
cavernous,  14 
costomediastinal,  194 
costophrenic,  194 
ethmoidal,  73,  102 
in  childhood,  10 
suppuration  in,  102 
drainage  of,  102 
frontal,  10,  45,  loi 
in  childhood,  10 
operation  on,  102 


626 


INDEX. 


Sinuses,  frontal,  suppuration  in,  loi 
drainage  of,  102 
lateral,  12 

relations  of  brain  to,  93 
thrombosis  of,  89,  90 
maxillary,  loi,  103 
disease  of,  103 
in  childhood,  10 
operations  on,  103 
occipital,  13 
petrosal,  inferior,  13 

superior,  13 
pocularis,  454 
sigmoid,  13 
sphenoidal,  103 

in  childhood,  10 
suppuration  in,  103 
drainage  of,  103 
sphenoparietal,  13 
straight,  13 

superior  longitudinal,  12 
transverse,  12 
urogenital,  453 
Skin  of  abdomen,  374 
Skull,  8 

in  adults,  10 

cerebral  venous  sinuses,  1 2 
cavernous,  13 
lateral  or  transverse,  12 
occipital,  13 
sigmoid,  13 
straight,  13,  31 
superior  longitudinal,  1 2 
superior  and  inferior  petrosal,  13 
torcular  Herophili,  12 
fractures  of,  15 

by  contrecoup,  16 
hemorrhage  in,  16 
injury  to  nerves  in,  19 
frontal  sinuses,  10,  10 1 
mastoid  cells,  11 

operations  on,  91 
mastoid  process,  11 
suprameatal  triangle,  12,  91 
sutures,  11 
tables  of,  10 
trephining,  18,  44 
in  childhood,  8 

cells  and  air  sinuses,  9 

ethmoidal  sinus,  9 
frontal  sinus,  9 
mastoid  antrum,  9 
maxillary  sinus,  9 
sphenoidal  sinus,  9 
dura,  9 
fontanelles,  8 
fractures  of,  14 
Snuff-box,  337 

Sound,  urethral,  passage  of,  471 
Speech  centre,  35 
Spermatic  artery,  385 
cord,  385,  469 

sheath  of,  469 
varicocele,  469 

operations  for,  469 
vessels  of,  469 
Spheno-ethmoidal  recess,  10 1 
Sphenoidal  sinus  (see  Sinus) 
Sphenoid  bone,  8 
Sphenoparietal  sinus,  13 
Spina  bifida,  480 

operation  on,  480 
Spinal  accessory  nerve,  20 


Spinal  accessory  nerve,  injury  to,  in  fractures  of 
skull,  20 
column,  478 

caries  of,  4S0 
curves  of,  478 
deformities  of,  478 
kyphosis,  479 
lordosis,  479 
scoliosis,  479 
spina  bifida,  480 
deviations  of,  above  the  sacrum,  495 
injuries  to,  481 

dislocations  of,  481 
fractures  of,  482 

nervous  lesions  in,  484 
laminectomy,  489 
movements  of,  478 
psoas  abscess,  481 
spinal  cord,  482 

meninges,  484 
spinous  processes,  477 
vertebrae  of,  478 
cord,  482 

cervical  enlargement,  482 
functions  of,  487 
hemorrhage  into,  486 
extradural,  486 
hematomyelia,  486 
intradural,  486 
lesions  of,  487 

of  gray  matter,  487 
transverse,  483 

localization  of,  483,  484 
muscular  paralysis  in,  484 
of  white  matter,  488 
lumbar  enlargement,  482 
meninges  of,  484 
arachnoid,  485 
dura,  484 
pia,  485 
operations  on,  488 

laminectomy,  489 
spmal  puncture,  488 
segments  of,  483 

lesions  of,  484 
spinal  localization,  487 
tracts  of,  487 
vessels  of,  485 
localization,  487 
meninges  (see  Spinal  cord) 
puncture,  488 
Spine,  anterior  inferior,  of  ilium,  500,  504 
superior,  of  ilium,  500,  504 
posterior  inferior,  of  ilium,  504 
superior,  of  ilium,  500,  504 
of  Spix,  117 
suprameatal,  91 
Spleen,  373,  424 

ligaments  of,  424 
position  of,  374 
relations  of,  424 
splenic  enlargements,  424 
wounds  of,  424 
Splenic  artery,  403 

flexure  of  colon,  374 
Sprain  of  ankle,  556 

treatment,  556 
of  subastragaloid  joint,  565 
Staphyloma,  anterior,  77 

posterior,  77 
Stenson's  duct,  51 
Stephanion,  40 
Sternoclavicular  joint,  22a 


INDEX. 


627 


Stcmomastoid  muscle,  4 

division  of,  for  torticollis,  140 
Sternum,  174 

fractures  of,  174 
Stimson,  abdominal  incision  of,  382 
Stomach,  373,  401 

blood-supply  of,  403 
carcinoma  of,  404 

adhesions  in,  405 
perforation  of,  405 
ulceration  in,  405 
cardiac  end,  373,  402 
contracted  stomach,  401,  403 
dilatation  of,  403 
fundus  of,  373 
gastro  ptosis,  403 
hour-glass  deformity  of,  401 
lower  border,  373 
lymphatics  of,  403 
operations  on,  405 

gastrectomy,  405 
gastro -enterostomy,  406 
gastroplication,  405 
gastrostomy,  405 
gastrotomy,  405 
pylorectom}^  405 
pyloroplasty,  405 
percussion  of,  482 
position  of,  399,  402 
pylorus,  373,  402 
relations  of,  402 
Traube's  semilunar  space,  402 
ulcer  of,  403 

perforation  of,  404 
veins  of,  403 
Straight  sinus,  13,  31 
Stricture  of  oesophagus,  212 

of  urethra,  472 
Studsgaard  operation  for  excision  of  wrist,  347 
Stye,  83 
Styloid  process  of  radius,  332 

of  ulna,  303 
Subacromial  bursa,  255 
Subaponeurotic  layer  of  scalp,  2 
Subarachnoid  space,  22 
Subastragaloid  joint,  564 
ligaments  of,  565 
sprain  of,  566 
Subclavian  artery,  147 

ligation  of,  148 
Subdiaphragmatic  abscess,  420,  423 
Subfemoral  bursa,  535 
Submammary  abscess,  185 
Submaxillary  gland,  132 
capsule  of,  153 
Submental  region,  129 
Subpericranial  tissue  of  scalp,  3 
Subperitoneal  fat,  399 
Subscapular  artery,  260 

bursa,  255 
Superciliary  ridges,  45 
Superficial  fascia  of  scalp,  i 

of  abdomen,  374 
Superior  longitudinal  sinus,  12 
parietal  gyrus,  ^;^ 
petrosal  sinus,  13 
Supination  of  forearm,  304 
Supramarginal  gyrus,  33 
Suprameatal  spine,  91 

triangle,  12,  91 
Supra-orbital  nerve,  45 

operation  on,  46 
neuralgia,  45 


Supra-orbital    neuralgia,  operation  for,  46 
Suprarenal  gland,  430 
Suprasternal  notch,  180 

pus  in,  154 
Surgical  kidney,  428 
Sustentaculum  tali,  571 
Sutures  of  skull,  1 1 
Sylvian  point,  40,  42 
Sylvius,  fissure  of,  28,  33 
Syme's  amputation,  559 
Synechia,  anterior,  79 

posterior,  79 
Syringomyelia,  488 

Tabes  dorsalis,  488 
Taenia  semicircularis,  30 
Talipes  calcaneus  and  cavus,  578 
treatment,  579 
equinus,  578 

treatment,  578 
planus,  577  • 

treatment,  578 
valgus,  577 

treatment,  578 
varus,  576 

treatment,  576 
Tarsometatarsal  amputation,  575 
Telangiectasis,  7 
Temporal  artery,  3,  48,  52 
bones,  8 

convolutions  of  the  brain,  334 
fascia,  47 
muscle,  65 
region,  46 
ridge,  39 
Temporomandibular  articulation,  64 

ligaments  of,  64 
Temporosphenoidal  lobe  of  brain,  32 

blood-supply  of,  29 
Tendon  or  tendons: 
conjoined,  388 
of  foot,  571 

location  of,  571 
of  hand,  356 

wounds  of,  364 
sheaths  of  hand,  suppuration  in,  366 
tendo  Achillis,  557 

actioh  in  fracture  of  fibula,  558 

of  tibia,  551 
tenotomy  of,  552,  558 
tendo  calcaneus  (Achillis),  557 
Tendo-oculi,  82 
Tenon,  capsule  of,  74 
Tentorium  cerebelli,  20 
Testicle,  468 

abscess  of,  469 
castration,  469 
coverings  of,  469 
descent  of,  383,  468 
development  of,  383,  453 
epididymis,  468 

epididymitis,  469 
hernia  of,  469 
hydrocele,  384,  468 
orchitis,  469 
size  and  position  of,  468 
undescended,  468 
Thalamus,  30,  31 

blood-supply  of,  28 
functions  of,  37 
Thenar  eminence,  353 
Thigh,  519 

amputation,  532 


628 


INDEX. 


Thigh,  amputation  ofr^t  ftip-jdlnt,  532 
femoral  artery   523 
femur,  fractures  of  (see  Fractures) 
Hunter's  canal,  524 
lymphatics  of  groin,  527 
excision  of,  527 
muscles  of,  520 

adductors,  522 
extensors,  520 
flexors,  520 
saphenous  vein,  long  or  internal,  525 

varicosities  of,  526 
Scarpa's  triangle,  522 
sciatic  nerve,  527 
sciatica,  528 
structure  of,  519 
surface  anatomy  of,  522 
Thoracic  duct,  140,  214 
wounds  of,  214 
Thorax  (see  Chest),  171 

surface  anatomy  of,  18 
Thumb, 

amputation  of,  368 

carpometacarpal,  369 
distal  phalanx,  368 
metacarpophalangeal,  369 
dislocation  of  proximal  phalanx  of,  362 
Thyroglossal  duct,  107 

in  cervical  fistulae,  170 
Thyroid  cartilage,  125 

fracture  of,  125 
gland,  164 

arteries  of,  164 
capsule  of,  153 
operations  on,  163 
parathyroid,  166 
venis  of,  165 
Thyrotomy,  161 
Tibia,  534 

fractures  of,  551 
Tibial  artery,  anterior,  598 
ligation  of,  548 
posterior,  549 

ligation  of,  549 
Tibiofibular  joint,  inferior,  554 

ligaments  of,  554 
Toes  (see  Foot) 
Tongue,  107 

arteries  of,  no 
cancer  of,  no 
excision  of,  1 10 
foramen  caecum  of,  107 
glossitis,  no 

incisions  in,  no 
glosso-epiglottic  folds,  108 
lingual  tonsil,  108 
mucous  cysts  of,  no 
papillae  of,  107 

circum  vallate,  107 
filiform  of,  107 
fungiform  of,  107 
removal  of,  no 
tongue-tie,  treatment,  108 
Tonsil,  faucial,  113 

blood-supply  of,  114 

capsule  of,  114,  116 

enucleation  of,  115 

hypertrophy  of,  115 

peritonsillar  abscess,  115 

relation  to  internal  carotid  artery,  315 

removal  of,  115 

supratonsillar  fossa,  113 

tumors  of,  114 


Tonsil,  lingual,  108 
Luschka's,  122 
pharyngeal,  122 
Tonsillitis,  1 14 

Topographical  points  of  bram,  40 
Topography,  craniocerebral,  39 
Torcular  Herophili,  12 
Torticollis,  140 
Tracheal  region,  129 
Tracheotomy,  162 
Transversalis  fascia,  399 

muscle,  378 
Transverse  sinuses,  12 
spinal  lesions,  483 
Trapezium,  350 
Trapezius  muscle,  4 
Trapezoid  bone,  350 

ligament,  222 
Traube's  semilunar  space,  40  a 
Treitz,  ligament  of,  406 
Trephining,  44 

for  middle  meningeal  hemorrhage,  18 
for  posterior  branch  of  middle  meningeal,  li 
Triangle,  anal  (see  Perineum,  male) 
Bryant's,  505 
fascial,  394 
Hesselbach's,  387 
of  Lesser,  146 
of  neck,  131 

anterior,  131;  posterior,  137 
Petit's,  377,  394 
Scarpa's,  522 

suboccipital,  fig.  182,  p.  160 
suprameatal,  12 

urogenital  (see  Perineum,  male) 
Triangular  fascia,  377 
ligament,  473 

anterior  or  superficial  layer,  473 
posterior  or  deep  layer,  473 
Triceps  muscle,  270,  286 

fascial  expansion  of,  270 

in  resection  of  elbow,  301 
Trifacial  nerve,  area  of  distribution  of,  63 
Gasserian  ganglion,  60 

operations  on,  60 
infraorbital  branch,  56 
removal  of,  56 
injury  to,  in  fractures  of  skull,  2C 
lingual  branch,  60 

excision  of,  60 
mandibular  branch,  60 

excision,  60 
maxillary  branch,  56 

operation  on,  58 
Meckel's  ganglion,  57 

removal  of,  57 
supra-orbital  branch,  45 
removal  of,  45 
Trigone  of  bladder,  446 
Trochlea,  280 
Tube,  Eustachian,  84,  89 

Fallopian,  456 
Tubercle,  carotid,  149 
dorsal  radial,  331 
of  OS  calcis,  571 
of  scaphoid  bone,  57: 
Tuberculosis  of  ankle,  55.5 
of  hip,  515 
of  knee,  543 
of  meninges,  23 
Tuberosity  of  fifth  metatarsal  bone,  571 

of  ischium,  501 
Tumors  of  axilla,  265 


INDEX. 


629 


Tumors  of  bladder,  448 

of  broad  ligament,  462 

of  kidney,  427 

of  mammary  gland,  185 

of  parotid  gland,  54 

of  scalp,  7 
Tunica  albuginea,  469 

vaginalis,  469 
Turbinated  bone,  inferior,  8,  44,  97,  118 
hypertrophy  of,  118 
middle,  97,  118 
superior,  97 
Tympanic  membrane  (see  Ear) 
Tympanomastoid  exenteration,  91,  92 
Tympanum  (see  Ear) 

Ulcer,  gastric,  403 
Ulna,  281,  303 

dislocation  of,  at  inferior  radio-ulnar  joint,  345 
epiphysis  of,  upper,  300 

separation  of,  300 
fracture  of  lower  end,  344 
treatment,  344 
'  olecranon  process,  298 
treatment,  298 
shaft,  325 

below  middle,  325 

treatment,  325 
upper  third,  325 

treatment,  326 

lower  end  of,  332 

upper  lend  of,  281 

Ulnar  artery,  314,  358 

in  hand,  358 

branches  of,  359 
ligation  of,  in  forearm,  316 
lower  third,  317 
middle  third,  316 
upper  third,  316 
nerve,  320 

distribution  in  hand,  360 
operations  on,  320 
wounds  of,  320 
Umbilical  arteries,  371,  382 
hernia  (see  Hernia) 
legion  of  abdomen,  370 
veins,  371 
Umbilicus,  371 
Unciform  bone,  350 
Urachus,  382,  387 
Ureter,  430 

abdominal  portion,  431 
course  of,  431 
excision  of,  431 
operation  on,  431 
calculi  in,  431 
in  female,  457 
points  of  narrowing,  431 
relation  of,  to  genitocrural  nerve,  431 
Urethra,  male,  470 

calibre  of,  470 

distensibility,  ^70 

length  of,  470 

muscles  of,  471 

passage  of  catheters  and  sounds,  471 

practical  applications,  471 

relations  of,  470 

rupture  of,  475 

treatment  of,  475 
stricture  of,  471 

spasmodic,  472 
traum.atic,  472 
structure,  470 


Urethral  crest,  471 

Urogenital  system,  development  of,  453 

triangle  (see  Perineum,  male) 
Uterine  artery,  458 
Uterovesical  fold,  398 
Uterus,  454 

anteflexion  of,  459 

anteversion  of,  459 

attachments  of,  455 

blood-supply  of,  458 

broad  ligament  of,  455 

cervix,  454 

lacerations  of,  462 

development  of,  453 

hysterectomy,  460,  461 
vaginal,  462 

ligaments  of,  455 

lymphatics  of,  458 

position  of,  454 

retroflexion,  459 

retroversion,  459 
Uvula,  112 

Vagina,  457 

development  of,  453 
fornix,  anterior,  457 
posterior,  457 
Vagus  nerve,  20 

injury  to,  in  fractures  of  skull,  20 
Valve  or  valves: 
Gerlach,  412 
ileocaecal,  374,  412 
of  heart,  206 

of  rectum  (Houston),  439 
Varicocele,  469 
Varicose  aneurism,  7 

veins  of  leg,  526,  550 

operation  for,  551 
Vas  deferens,  385,  452,  469 
Vater,  ampulla  of,  407 

stone  in,  422  .     ■ 

Vein  or  veins: 

of  abdominal  walls,  380 
celiotomy,  380 
choroid  plexus  of,  30 
coronary,  403 
cystic,  420 
deferential,  469 
of  elbow,  288 
epigastric,  deep,  380 
superficial,  380 
superior,  380 
ethmoidal,  anterior,  98 

posterior,  98 
femoral,  523 
of  Galen,  31 
gastric,  420 
gastro-epiploic,  left,  403 

right,  403 
hemorrhoidal, 
inferior,  441 
middle,  441 
superior,  420,  441 
ileocolic,  413 
iliac,  436 

position  of,  374 
iliac,  circumflex,  deep,  380 

superficial,  380 
jugular,  anterior,  135 
external,  138 
internal,  136 

thrombosis  of,  136 
wounds  of,  136 


630 


INDEX. 


Veins  of  leg,  550 

median,  288 

median  basilic,  289 

median  cephalic,  2S9 

mesenteric,  superior,  420 

of  nose,  98 

ophthalmic,  inferior,  81 
superior,  81 

pampiniform  plexus  of,  385 

portal,  420 

of  prostate  gland,  450 

pyloric,  403,  420 

radial,  288 

renal,  426 

saphenous,  long  or  internal,  525,  550 

excision  of,  for  varicose  veins,  551 
short  or  external,  550 

of  spinal  cord,  480 

splenic,  420 

of  thyroid  gland,  165 

ulnar,  289 

umbilical,  371 

vena  parumbilicalis,  380 

vena    thoracica    epigastrica    longa    tegumen- 
tosa,  380 

venous  plexuses  of  rectum,  441 

vertebral  plexuses,  484,  486 
Velum  interpositum,  31 
Venous  angioma,  7 
Ventricles,  fifth,  of  brain,  30 

lateral,  of  brain,  30,  43 
tapping  of,  43 

third,  of  brain,  30 

blood-supply  of,  28 
Vertebrae,  thoracic,  176 
Vertebral  artery,  25,  147 

column  (see  Spinal  column) 
Vestibule  of  vagina,  462 
Viscera,  abdominal,  372,  399 
position  of,  372,  399 

pelvic,  438 
Visual  area  of  brain,  37 
Vitelline  duct,  371,  382 
Vomer,  8 
Vulvo-vaginal  glands,  463 

Walking,  498 

part  played  by  various  joints  in,  499 
Walther,  ducts  of,  108 
Weir's  abdominal  incision,  383 


Wharton,  duct  of,  108 
Whitlow,  367 
Winslow,  foramen  of,  398 
Wirsung,  duct  of,  423 
Wolffian  body,  453 

duct,  453 
Wounds  of  cheek,  49 

of  epigastric  artery,  deep,  379 

in  abdominal  operations,  380 
superior,  379 
of  hand,  364 
of  heart,  207 

operation  for,  207 
of  lips,  104 
of  liver,  420 
of  parotid  duct,  51 
of  scalp,  4 
of  spleen,  424 
of  thoracic  duct,  214 
Wrisberg,  cartilages  of,  1 24 

ligament  of,  537 
Wrist,  330 

amputation  at,  347 

annular  ligament,  anterior,  335 

structures  passing  beneath,  336 
structures  passing  over,  336 
posterior,  336 

structures  passing  beneath,  337 
bones  of,  330 

compound  ganglion  of,  342 
deep  fascia  of,  335 
dislocations  of,  345 

at  radiocarpal  joint,  345 
at  radio-ulnar  joint,  345 
wrist-drop,  334 
excision  of,  345 
fractures  of,  Colles's,  342 

lower  end  of  radius  and  ulna,  342 
inferior  radio-ulnar  articulation,  332 
ligaments  of,  ^^^ 

movements  of,  ^33 
ligation  of  radial  artery  on  dorsum  of  hand. 

348 
muscles  of,  335 
snuff-box,  337 
surface  anatomy  of,  338 
tendons  of,  336 
Wrist-joint,  $;ii 

ligaments  of,  333 
movements  of,  333 


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